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  • FMOD surround sound openframeworks

    - by user1449425
    Ok, I hope I don't mess this up, I have had a look for some answers but can't find anything. I am trying to make a simple sampler in openframeworks using the FMOD sound player in 3D mode. I can make a single instance work fine (recording a new file using libsndfilerecorder and then playing it back and moving it in surround. However I want to have 8 layers of looping audio that I can record and replace one layer at a time in a live show. I get a lot of problems as soon as I have more than 1 layer. The first part of my question relates to the FMOD 3D modes, it is listener relative, so I have to define the position of my listener for every sound (I would prefer to have head relative mode but I cannot make this work at all. Again this works fine when I am using a single player but with multiple players only the last listener I update actually works. The main problem I have is that when I use multiple players I get distortion, and often a mix of other currently playing sounds (even when the microphone cannot hear them) in my new recordings. Is there an incompatability with libsndfilerecorder and FMOD? Here I initialise the players for (int i=0; i<CHANNEL_COUNT; i++) { lvelocity[i].set(1, 1, 1); lup[i].set(0, 1, 0); lforward[i].set(0, 0, 1); lposition[i].set(0, 0, 0); sposition[i].set(3, 3, 2); svelocity[i].set(1, 1, 1); //player[1].initializeFmod(); //player[i].loadSound( "1.wav" ); player[i].setVolume(0.75); player[i].setMultiPlay(true); player[i].play(); setupHold[i]==false; recording[i]=false; channelHasFile[i]=false; settingOsc[i]=false; } When I am recording I unload the file and make sure the positions of the player that is not loaded are not updating. void fmodApp::recordingStart( int recordingId ){ if (recording[recordingId]==false) { setupHold[recordingId]=true; //this stops the position updating cout<<"Start recording Channel " + ofToString(recordingId+1)+" setup hold is true \n"; pt=getDateName() +".wav"; player[recordingId].stop(); player[recordingId].unloadSound(); audioRecorder.setup(pt); audioRecorder.setFormat(SF_FORMAT_WAV | SF_FORMAT_PCM_16); recording[recordingId]=true; //this starts the libSndFIleRecorder } else { cout<<"Channel" + ofToString(recordingId+1)+" is already recording \n"; } } And I stop the recording like this. void fmodApp::recordingEnd( int recordingId ){ if (recording[recordingId]=true) { recording[recordingId]=false; cout<<"Stop recording" + ofToString(recordingId+1)+" \n"; audioRecorder.finalize(); audioRecorder.close(); player[recordingId].loadSound(pt); setupHold[recordingId]=false; channelHasFile[recordingId]=true; cout<< "File recorded channel " + ofToString(recordingId+1) + " file is called " + pt + "\n"; } else { cout << "Sorry track" + ofToString(recordingId+1) + "is not recording"; } } I am careful not to interrupt the updating process but I cannot see where I am going wrong. Many Thanks

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  • simplejson double escapes data causing invalid JSON string

    - by mike_hornbeck
    I have a simple form for managing manufacturers in my shop. After posting form, ajax call returns json with updated data to the form. Problem is, that the returned string is invalid. It looks like it was double-escaped. Strangely similar approach across the whole shop works without any problems. I'm also using jquery 1.6 as javascript framework. Model contains of 3 fields : char for name, text for description and image field for manufacturer logo. The function : def update_data(request, manufacturer_id): """Updates data of manufacturer with given manufacturer id. """ manufacturer = Manufacturer.objects.get(pk=manufacturer_id) form = ManufacturerDataForm(request.FILES, request.POST, instance=manufacturer) if form.is_valid(): form.save() msg = _(u"Manufacturer data has been saved.") html = [ ["#data", manufacturer_data_inline(request, manufacturer_id, form)], ["#selectable-factories-inline", selectable_manufacturers_inline(request, manufacturer_id)], ] result = simplejson.dumps({ "html": html }, cls=LazyEncoder) return HttpResponse(result) The error in console : error with invalid JSON : uncaught exception: Invalid JSON: {"html": [["#data", "\n<h2>Dane</h2>\n<div class="\&quot;manufacturer-image\&quot;">\n \n</div>\n<form action="\&quot;/manage/update-manufacturer-data/1\&quot;" method="\&quot;post\&quot;">\n \n <div class="\&quot;field\&quot;">\n <div class="\&quot;label\&quot;">\n <label for="\&quot;id_name\&quot;">Nazwa</label>:\n </div>\n \n \n <div class="\&quot;error\&quot;">\n <input id="\&quot;id_name\&quot;" name="\&quot;name\&quot;" maxlength="\&quot;50\&quot;" type="\&quot;text\&quot;">\n <ul class="\&quot;errorlist\&quot;"><li>Pole wymagane</li></ul>\n </div>\n \n </div>\n\n <div class="\&quot;field\&quot;">\n <div class="\&quot;label\&quot;">\n <label for="\&quot;id_image\&quot;">Zdjecie</label>:\n </div>\n \n \n <div>\n <input name="\&quot;image\&quot;" id="\&quot;id_image\&quot;" type="\&quot;file\&quot;">\n </div>\n \n </div>\n\n <div class="\&quot;field\&quot;">\n <div class="\&quot;label\&quot;">\n <label for="\&quot;id_description\&quot;">Opis</label>:\n </div>\n \n \n <div>\n <textarea id="\&quot;id_description\&quot;" rows="\&quot;10\&quot;" cols="\&quot;40\&quot;" name="\&quot;description\&quot;"></textarea>\n </div>\n \n </div>\n \n <div class="\&quot;buttons\&quot;">\n <input class="\&quot;ajax-save-button" button\"="" type="\&quot;submit\&quot;">\n </div>\n</form>"], ["#selectable-factories-inline", "\n <div>\n <a class="\&quot;selectable" selected\"\n="" href="%5C%22/manage/manufacturer/1%5C%22">\n L1\n </a>\n </div>\n\n <div>\n <a class="\&quot;selectable" \"\n="" href="%5C%22/manage/manufacturer/4%5C%22">\n KR3W\n </a>\n </div>\n\n <div>\n <a class="\&quot;selectable" \"\n="" href="%5C%22/manage/manufacturer/3%5C%22">\n L1TA\n </a>\n </div>\n\n"]]} Any ideas ?

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  • Blackberry XML Parsing Application not working

    - by Nirmal
    Hello All... I found one sample application from the Blackberry knowledgebase. From that application I have put that sample application on my eclipse plugin, and the code is as follows : import javax.microedition.io.*; import net.rim.device.api.ui.*; import net.rim.device.api.ui.component.*; import net.rim.device.api.ui.container.*; import net.rim.device.api.system.*; import net.rim.device.api.xml.parsers.*; import org.w3c.dom.*; import org.xml.sax.*; class XML_Parsing_Sample extends UiApplication { // creating a member variable for the MainScreen MainScreen _screen = new MainScreen(); // string variables to store the values of the XML document String _node, _element; Connection _connectionthread; public static void main(String arg[]) { XML_Parsing_Sample application = new XML_Parsing_Sample(); // create a new instance of the application // and start the application on the event thread application.enterEventDispatcher(); } public XML_Parsing_Sample() { _screen.setTitle("XML Parsing");// setting title _screen.add(new RichTextField("Requesting.....")); _screen.add(new SeparatorField()); pushScreen(_screen); // creating a screen // creating a connection thread to run in the background _connectionthread = new Connection(); _connectionthread.start();// starting the thread operation } public void updateField(String node, String element) { // receiving the parsed node and its value from the thread // and updating it here // so it can be displayed on the screen String title = "My App"; _screen.add(new RichTextField(node + " : " + element)); if (node.equals(title)) { _screen.add(new SeparatorField()); } } private class Connection extends Thread { public Connection() { super(); } public void run() { // define variables later used for parsing Document doc; StreamConnection conn; try { // providing the location of the XML file, // your address might be different conn = (StreamConnection) Connector .open("http://www.sufalamtech.com/demo/moviewebservice/Test.xml"); // next few lines creates variables to open a // stream, parse it, collect XML data and // extract the data which is required. // In this case they are elements, // node and the values of an element DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory .newInstance(); DocumentBuilder docBuilder = docBuilderFactory .newDocumentBuilder(); docBuilder.isValidating(); doc = docBuilder.parse(conn.openInputStream()); doc.getDocumentElement().normalize(); NodeList list = doc.getElementsByTagName("*"); _node = new String(); _element = new String(); // this "for" loop is used to parse through the // XML document and extract all elements and their // value, so they can be displayed on the device for (int i = 0; i < list.getLength(); i++) { Node value = list.item(i).getChildNodes().item(0); _node = list.item(i).getNodeName(); _element = value.getNodeValue(); updateField(_node, _element); }// end for }// end try // will catch any exception thrown by the XML parser catch (Exception e) { Dialog.alert("exception = " + e); } }// end connection function }// end connection class }// end XML_Parsing_Sample But when I am running this application, the simulator just showing me a Blank screen with label Requesting... Anybody help me out for this ? Thanks in advance...

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  • Cant bind data to a table view

    - by sudhakarilla
    Hi, I have retrieved data from Json URL and displayed it in a table view. I have also inlcuced a button in table view. On clicking the button the data must be transferred to a another table view. The problem is that i could send the data to a view and could display it on a label. But i couldnt bind the dat to table view ... Here's some of the code snippets... Buy Button... -(IBAction)Buybutton{ /* UIAlertView *alert =[[UIAlertView alloc]initWithTitle:@"thank u" message:@"products" delegate:nil cancelButtonTitle:@"ok" otherButtonTitles:nil]; [alert show]; [alert release];*/ Product *selectedProduct = [[data products]objectAtIndex:0]; CartViewController *cartviewcontroller = [[[CartViewController alloc] initWithNibName:@"CartViewController" bundle:nil]autorelease]; cartviewcontroller.product= selectedProduct; //NSString *productname=[product ProductName]; //[currentproducts setproduct:productname]; [self.view addSubview:cartviewcontroller.view]; } CartView... // Implement viewDidLoad to do additional setup after loading the view, typically from a nib. - (void)viewDidLoad { [super viewDidLoad]; data = [GlobalData SharedData]; NSMutableArray *prod =[[NSMutableArray alloc]init]; prod = [data products]; for(NSDictionary *product in prod) { Cart *myprod = [[Cart alloc]init]; myprod.Description = [product Description]; myprod.ProductImage =[product ProductImage]; myprod.ProductName = [product ProductName]; myprod.SalePrice = [product SalePrice]; [data.carts addObject:myprod]; [myprod release]; } Cart *cart = [[data carts]objectAtIndex:0]; NSString *productname=[cart ProductName]; self.label.text =productname; NSLog(@"carts"); } (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { return 1; } (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return [data.carts count]; } -(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath { return 75; } (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { NSLog(@"cellforrow"); static NSString *CellIdentifier = @"Cell"; ProductCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if(cell ==nil) { cell = [[[ProductCell alloc]initWithFrame:CGRectZero reuseIdentifier:CellIdentifier]autorelease]; } NSUInteger row = [indexPath row]; Cart *cart = [[data carts]objectAtIndex:row]; cell.productNameLabel.text = [cart ProductName]; /*NSString *sale = [[NSString alloc]initWithFormat:@"SalePrice:%@",[cart SalePrice]]; cell.salePriceLabel.text = sale; cell.DescriptionLabel.text = [cart Description]; NSMutableString imageUrl =[NSMutableString string]; [imageUrl appendFormat:@"http://demo.s2commerce.net/DesktopModules/S2Commerce/Images/Products/%@",[product ProductImage]]; NSLog(@"imageurl:%@",imageUrl); NSString mapURL = [imageUrl stringByReplacingPercentEscapesUsingEncoding:NSASCIIStringEncoding]; NSData* imageData = [[NSData alloc]initWithContentsOfURL:[NSURL URLWithString:mapURL]]; UIImage* image = [[UIImage alloc]initWithData:imageData]; cell.productImageview.image = image; [imageData release]; [image release];*/ return cell; } I am also getting the following error in the console 2010-06-11 18:34:29.169 navigation[4109:207] * -[CartViewController tableView:numberOfRowsInSection:]: message sent to deallocated instance 0xcb4d4f90

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  • How to remove the xmlns:XSI and xmlns:XSD namespaces from the xml output of a webservice in .net fra

    - by Chetan
    HI, This is an old question, i have seen some solutions on this forum itself, but am trying to use webservices for the first time so please bear with me on this one. I have a webservice that returns XML in the following format <subs xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" msisdn="965xxxxxx"> <shortcode label="XXXX"> <channels> <channel> <id>442</id> <name>News</name> <billingperiod>7</billingperiod> <billingamount>3</billingamount> <lastbilling>4/14/2010 1:41:11 PM</lastbilling> </channel> <channel> <id>443</id> <name>News2</name> <billingperiod>7</billingperiod> <billingamount>3</billingamount> <lastbilling>4/14/2010 1:41:19 PM</lastbilling> </channel> </channels> </shortcode> </subs> I want the same XMl output without the xmlns:xsd and xmlns:xsi tags. I have tried the following solution that was suggested: Public Function GetSubscription(....) As String Dim namespaces As New XmlSerializerNamespaces namespaces.Add(String.Empty, String.Empty) Dim serializer As New XmlSerializer(SubsDetail.GetType) Dim sw As New System.IO.StringWriter Dim writer As New System.Xml.XmlTextWriter(sw) writer.Formatting = Formatting.None serializer.Serialize(writer, SubsDetail, namespaces) writer.Close() Return sw.toString() The result was that I got an xml in the following format: <string> <?xml version="1.0" encoding="utf-16"?><subs msisdn="965xxxx"> <shortcode label="XXXX"> <channels> <channel> <id>442</id> <name>News</name> <billingperiod>7</billingperiod> <billingamount>3</billingamount> <lastbilling>4/14/2010 1:41:11 PM</lastbilling> </channel> <channel> <id>443</id> <name>News2</name> <billingperiod>7</billingperiod> <billingamount>3</billingamount> <lastbilling>4/14/2010 1:41:19 PM</lastbilling> </channel> </channels> </shortcode> </subs> </string> Though the format of the xml is correct it is coming as string within the <string> tags. This is really driving me nuts. Can I get the output as xml without the outer string tags?

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  • WCF Endpoints & Binding Configuration Issues

    - by CodeAbundance
    I am running into a very strange issue here folks. For simplicity I created a project for the sole purpose of testing the issue outside the framework of a larger application and still encountered what is either a bug in WCF within Visual Studio 2010 or something related to my WCF newbie skill set : ) Here is the issue: I have a WCF endpoint I created running inside of an MVC3 project called "SimpleMethod". The method runs inside of a .svc file on the root of the application and it returns a bool. Using the "WCF Service Configuration Editor" I have added the endpoint to my Web.Config along with a called "LargeImageBinding". Here is the service: [OperationContract] public bool SimpleMethod() { return true; } And the Web.Config generated by the Config Tool: <system.serviceModel> <bindings> <wsHttpBinding> <binding name="LargeImageBinding" closeTimeout="00:10:00" /> </wsHttpBinding> </bindings> <services> <service name="WCFEndpoints.ServiceTestOne"> <endpoint address="/ServiceTestOne.svc" binding="wsHttpBinding" bindingConfiguration="LargeImageBinding" contract="WCFEndpoints.IServiceTestOne" /> </service> </services> <behaviors> <serviceBehaviors> <behavior name=""> <serviceMetadata httpGetEnabled="true" /> <serviceDebug includeExceptionDetailInFaults="false" /> </behavior> </serviceBehaviors> </behaviors> <serviceHostingEnvironment multipleSiteBindingsEnabled="true" /> The service renders fine and you can see the endpoint when you navigate to: http://localhost:57364/ServiceTestOne.svc - Now the issue occurs when I create a separate project to consume the service. I add a service reference to a running instance of the above project, point it to: http://localhost:57364/ServiceTestOne.svc Here is the weird part. The service automatically generates just fine but In the Web.Config the endpoint that is generated looks like this: <client> <endpoint address="http://localhost:57364/ServiceTestOne.svc/ServiceTestOne.svc" binding="wsHttpBinding" bindingConfiguration="WSHttpBinding_IServiceTestOne" contract="ServiceTestOne.IServiceTestOne" name="WSHttpBinding_IServiceTestOne"> As you can see it lists the "ServiceTestOne.svc" portion of the address twice! When I make a call to the the service I get the following error: The remote server returned an error: (404) Not Found. I tried removing the extra "/ServiceTestOne.svc" at the end of the endpoint address in the above config, and I get the same exact error. Now what DOES work is if I go back to the WCF application and remove the custom endpoint and binding references in the Web.Config (everything in the "services" and "bindings" tags) then go back to the consumer application, update the reference to the service and make the call to SimpleMethod()....BOOM works like a charm and I get back a bool set to true. The thing is, I need to make custom binding configurations in order to allow for access to the service outside of the defaults, and from what I can tell, any attempt to create custom bindings makes the endpoints seem to run fine, but fail when an actual method call is made. Can anyone see any flaw in how I am putting this together? Thank you for your time - I have been running in circles with this for about a week!

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  • What is the fastest way to Initialize a multi-dimensional array to non-default values in .NET?

    - by AMissico
    How do I initialize a multi-dimensional array of a primitive type as fast as possible? I am stuck with using multi-dimensional arrays. My problem is performance. The following routine initializes a 100x100 array in approx. 500 ticks. Removing the int.MaxValue initialization results in approx. 180 ticks just for the looping. Approximately 100 ticks to create the array without looping and without initializing to int.MaxValue. Routines similiar to this are called a few hundred-thousand to several million times during a "run". The array size will not change during a run and arrays are created one-at-a-time, used, then discarded, and a new array created. A "run" which may last from one minute (using 10x10 arrays) to forty-five minutes (100x100). The application creates arrays of int, bool, and struct. There can be multiple "runs" executing at same time, but are not because performance degrades terribly. I am using 100x100 as a base-line. I am open to suggestions on how to optimize this non-default initialization of an array. One idea I had is to use a smaller primitive type when available. For instance, using byte instead of int, saves 100 ticks. I would be happy with this, but I am hoping that I don't have to change the primitive data type. public int[,] CreateArray(Size size) { int[,] array = new int[size.Width, size.Height]; for (int x = 0; x < size.Width; x++) { for (int y = 0; y < size.Height; y++) { array[x, y] = int.MaxValue; } } return array; } Down to 450 ticks with the following: public int[,] CreateArray1(Size size) { int iX = size.Width; int iY = size.Height; int[,] array = new int[iX, iY]; for (int x = 0; x < iX; x++) { for (int y = 0; y < iY; y++) { array[x, y] = int.MaxValue; } } return array; } Down to approximately 165 ticks after a one-time initialization of 2800 ticks. (See my answer below.) If I can get stackalloc to work with multi-dimensional arrays, I should be able to get the same performance without having to intialize the private static array. private static bool _arrayInitialized5; private static int[,] _array5; public static int[,] CreateArray5(Size size) { if (!_arrayInitialized5) { int iX = size.Width; int iY = size.Height; _array5 = new int[iX, iY]; for (int x = 0; x < iX; x++) { for (int y = 0; y < iY; y++) { _array5[x, y] = int.MaxValue; } } _arrayInitialized5 = true; } return (int[,])_array5.Clone(); } Down to approximately 165 ticks without using the "clone technique" above. (See my answer below.) I am sure I can get the ticks lower, if I can just figure out the return of CreateArray9. public unsafe static int[,] CreateArray8(Size size) { int iX = size.Width; int iY = size.Height; int[,] array = new int[iX, iY]; fixed (int* pfixed = array) { int count = array.Length; for (int* p = pfixed; count-- > 0; p++) *p = int.MaxValue; } return array; }

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  • NetworkOnMainThread exception occuring

    - by Akshat
    I got a code from Android Hive to parse JSON data from url. Then I am trying to implement the same code on Rotten Tomatoes Upcoming Movies Api. I have implemented the same code with almost modifying all the xml files according to my needs. But the problem is when I am trying to run the code, its showing NetworkOnMainThread Exception. This is my code.. public class Upcoming extends ListActivity { String url = "http://api.rottentomatoes.com/api/public/v1.0/lists/movies/upcoming.json?apikey=yvvgsv722gy2zkey3ebkda5t"; final String TAG_MOVIES = "movies"; final String TAG_ID = "id"; final String TAG_TITLE = "title"; final String TAG_YEAR = "year"; final String TAG_MPAA_RATING = "mpaa_rating"; final String TAG_RUNTIME = "runtime"; final String TAG_RELEASE_DATES = "release_dates"; final String TAG_RATINGS = "ratings"; final String TAG_CRITIC_RATING = "critics_ratings"; final String TAG_AUDIENCE_RATING = "audience_ratings"; final String TAG_SYNOPSIS = "synopsis"; final String TAG_POSTERS = "posters"; JSONArray upcomings = null; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_upcoming_list); ArrayList<HashMap<String, String>> UpcomingList = new ArrayList<HashMap<String, String>>(); // Creating JSON Parser instance JSONParser jParser = new JSONParser(); // getting JSON string from URL JSONObject json = jParser.getJSONFromUrl(url); try { // Getting Array of Contacts upcomings = json.getJSONArray(TAG_MOVIES); // looping through All Contacts for(int i = 0; i < upcomings.length(); i++){ JSONObject c = upcomings.getJSONObject(i); // Storing each json item in variable String id = c.getString(TAG_ID); String title = c.getString(TAG_TITLE); String year = c.getString(TAG_YEAR); String mpaa_rating = c.getString(TAG_MPAA_RATING); String runtime = c.getString(TAG_RUNTIME); JSONObject release_dates = c.getJSONObject(TAG_RELEASE_DATES); JSONObject ratings = c.getJSONObject(TAG_RATINGS); String critic_rating = c.getString(TAG_CRITIC_RATING); String audience_rating = c.getString(TAG_AUDIENCE_RATING); String synopsis = c.getString(TAG_SYNOPSIS); JSONObject posters = c.getJSONObject(TAG_POSTERS); HashMap<String, String> map = new HashMap<String, String>(); map.put(TAG_TITLE, title); map.put(TAG_YEAR, year); map.put(TAG_CRITIC_RATING, critic_rating); map.put(TAG_AUDIENCE_RATING, audience_rating); UpcomingList.add(map); } } catch (JSONException e) { e.printStackTrace(); } ListAdapter adapter = new SimpleAdapter(this, UpcomingList, R.layout.activity_upcoming, new String[] { TAG_TITLE, TAG_YEAR, TAG_CRITIC_RATING, TAG_AUDIENCE_RATING }, new int[] { R.id.title, R.id.year, R.id.critic_rating, R.id.audience_rating }); setListAdapter(adapter); // selecting single ListView item ListView lv = getListView(); // Launching new screen on Selecting Single ListItem lv.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { // getting values from selected ListItem String name = ((TextView) view.findViewById(R.id.title)).getText().toString(); String cost = ((TextView) view.findViewById(R.id.year)).getText().toString(); String critic_rating = ((TextView) view.findViewById(R.id.critic_rating)).getText().toString(); String audience_rating = ((TextView) view.findViewById(R.id.audience_rating)).getText().toString(); // Starting new intent Intent in = new Intent(getApplicationContext(), Upcoming.class); in.putExtra(TAG_TITLE, name); in.putExtra(TAG_YEAR, cost); in.putExtra(TAG_CRITIC_RATING, critic_rating); in.putExtra(TAG_AUDIENCE_RATING, audience_rating); startActivity(in); } }); } } Can anyone please help me with anything I am missing.? I am totally blind on it now. Thanx in advance.

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  • Where should I create my DbCommand instances?

    - by Domenic
    I seemingly have two choices: Make my class implement IDisposable. Create my DbCommand instances as private readonly fields, and in the constructor, add the parameters that they use. Whenever I want to write to the database, bind to these parameters (reusing the same command instances), set the Connection and Transaction properties, then call ExecuteNonQuery. In the Dispose method, call Dispose on each of these fields. Each time I want to write to the database, write using(var cmd = new DbCommand("...", connection, transaction)) around the usage of the command, and add parameters and bind to them every time as well, before calling ExecuteNonQuery. I assume I don't need a new command for each query, just a new command for each time I open the database (right?). Both of these seem somewhat inelegant and possibly incorrect. For #1, it is annoying for my users that I this class is now IDisposable just because I have used a few DbCommands (which should be an implementation detail that they don't care about). I also am somewhat suspicious that keeping a DbCommand instance around might inadvertently lock the database or something? For #2, it feels like I'm doing a lot of work (in terms of .NET objects) each time I want to write to the database, especially with the parameter-adding. It seems like I create the same object every time, which just feels like bad practice. For reference, here is my current code, using #1: using System; using System.Net; using System.Data.SQLite; public class Class1 : IDisposable { private readonly SQLiteCommand updateCookie = new SQLiteCommand("UPDATE moz_cookies SET value = @value, expiry = @expiry, isSecure = @isSecure, isHttpOnly = @isHttpOnly WHERE name = @name AND host = @host AND path = @path"); public Class1() { this.updateCookie.Parameters.AddRange(new[] { new SQLiteParameter("@name"), new SQLiteParameter("@value"), new SQLiteParameter("@host"), new SQLiteParameter("@path"), new SQLiteParameter("@expiry"), new SQLiteParameter("@isSecure"), new SQLiteParameter("@isHttpOnly") }); } private static void BindDbCommandToMozillaCookie(DbCommand command, Cookie cookie) { long expiresSeconds = (long)cookie.Expires.TotalSeconds; command.Parameters["@name"].Value = cookie.Name; command.Parameters["@value"].Value = cookie.Value; command.Parameters["@host"].Value = cookie.Domain; command.Parameters["@path"].Value = cookie.Path; command.Parameters["@expiry"].Value = expiresSeconds; command.Parameters["@isSecure"].Value = cookie.Secure; command.Parameters["@isHttpOnly"].Value = cookie.HttpOnly; } public void WriteCurrentCookiesToMozillaBasedBrowserSqlite(string databaseFilename) { using (SQLiteConnection connection = new SQLiteConnection("Data Source=" + databaseFilename)) { connection.Open(); using (SQLiteTransaction transaction = connection.BeginTransaction()) { this.updateCookie.Connection = connection; this.updateCookie.Transaction = transaction; foreach (Cookie cookie in SomeOtherClass.GetCookieArray()) { Class1.BindDbCommandToMozillaCookie(this.updateCookie, cookie); this.updateCookie.ExecuteNonQuery(); } transaction.Commit(); } } } #region IDisposable implementation protected virtual void Dispose(bool disposing) { if (!this.disposed && disposing) { this.updateCookie.Dispose(); } this.disposed = true; } public void Dispose() { this.Dispose(true); GC.SuppressFinalize(this); } ~Class1() { this.Dispose(false); } private bool disposed; #endregion }

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  • Drawing outlines around organic shapes

    - by ThunderChunky_SF
    One thing that seems particularly easy to do in the Flash IDE but difficult to do with code is to outline an organic shape. In the IDE you can just use the inkbucket tool to draw a stroke around something. Using nothing but code it seems much trickier. One method I've seen is to add a glow filter to the shape in question and just mess with the strength. But what if i want to only show the outline? What I'd like to do is to collect all of the points that make up the edge of the shape and then just connect the dots. I've actually gotten so far as to collect all of the points with a quick and dirty edge detection script that I wrote. So now I have a Vector of all the points that makeup my shape. How do I connect them in the proper sequence so it actually looks like the original object? For anyone who is interested here is my edge detection script: // Create a new sprite which we'll use for our outline var sp:Sprite = new Sprite(); var radius:int = 50; sp.graphics.beginFill(0x00FF00, 1); sp.graphics.drawCircle(0, 0, radius); sp.graphics.endFill(); sp.x = stage.stageWidth / 2; sp.y = stage.stageHeight / 2; // Create a bitmap data object to draw our vector data var bmd:BitmapData = new BitmapData(sp.width, sp.height, true, 0); // Use a transform matrix to translate the drawn clip so that none of its // pixels reside in negative space. The draw method will only draw starting // at 0,0 var mat:Matrix = new Matrix(1, 0, 0, 1, radius, radius); bmd.draw(sp, mat); // Pass the bitmap data to an actual bitmap var bmp:Bitmap = new Bitmap(bmd); // Add the bitmap to the stage addChild(bmp); // Grab all of the pixel data from the bitmap data object var pixels:Vector.<uint> = bmd.getVector(bmd.rect); // Setup a vector to hold our stroke points var points:Vector.<Point> = new Vector.<Point>; // Loop through all of the pixels of the bitmap data object and // create a point instance for each pixel location that isn't // transparent. var l:int = pixels.length; for(var i:int = 0; i < l; ++i) { // Check to see if the pixel is transparent if(pixels[i] != 0) { var pt:Point; // Check to see if the pixel is on the first or last // row. We'll grab everything from these rows to close the outline if(i <= bmp.width || i >= (bmp.width * bmp.height) - bmp.width) { pt = new Point(); pt.x = int(i % bmp.width); pt.y = int(i / bmp.width); points.push(pt); continue; } // Check to see if the current pixel is on either extreme edge if(int(i % bmp.width) == 0 || int(i % bmp.width) == bmp.width - 1) { pt = new Point(); pt.x = int(i % bmp.width); pt.y = int(i / bmp.width); points.push(pt); continue; } // Check to see if the previous or next pixel are transparent, // if so save the current one. if(i > 0 && i < bmp.width * bmp.height) { if(pixels[i - 1] == 0 || pixels[i + 1] == 0) { pt = new Point(); pt.x = int(i % bmp.width); pt.y = int(i / bmp.width); points.push(pt); } } } }

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  • Load balancing using Mina example with Java DSL

    - by Flame_Phoenix
    So, recently I started learning Camel. As part of the process I decided to go through all the examples (listed HERE and available when you DOWNLOAD the package with all the examples and docs) and to see what I could learn. One of the examples, Load Balancing using Mina caught my attention because it uses a Mina in different JVM's and it simulates a load balancer with round robin. I have a few problems with this example. First it uses the Spring DSL, instead of the Java DSL which my project uses and which I find a lot easier to understand now (mainly also because I am used to it). So the first question: is there a version of this example using only the Java DSL instead of the Spring DSL for the routes and the beans? My second questions is code related. The description states, and I quote: Within this demo every ten seconds, a Report object is created from the Camel load balancer server. This object is sent by the Camel load balancer to a MINA server where the object is then serialized. One of the two MINA servers (localhost:9991 and localhost:9992) receives the object and enriches the message by setting the field reply of the Report object. The reply is sent back by the MINA server to the client, which then logs the reply on the console. So, from what I read, I understand that the MINA server 1 (per example) receives a report from the loadbalancer, changes it, and then it sends that report back to some invisible client. Upon checking the code, I see no client java class or XML and when I run, the server simply posts the results on the command line. Where is the client ?? What is this client? In the MINA 1server code presented here: <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:camel="http://camel.apache.org/schema/spring" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://camel.apache.org/schema/spring http://camel.apache.org/schema/spring/camel-spring.xsd"> <bean id="service" class="org.apache.camel.example.service.Reporting"/> <camelContext xmlns="http://camel.apache.org/schema/spring"> <route id="mina1"> <from uri="mina:tcp://localhost:9991"/> <setHeader headerName="minaServer"> <constant>localhost:9991</constant> </setHeader> <bean ref="service" method="updateReport"/> </route> </camelContext> </beans> I don't understand how the updateReport method magically prints the object on my console. What if I wanted to send message to a third MINA server? How would I do it? (I would have to add a new route, and send it to the URI of the 3rd server correct?) I know most of these questions may sound dumb, but I would appreciate if anyone could help me. A Java DSL version of this would really help me.

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  • Jquery autocomplete UI - No results on multiple fields

    - by pjammer
    Andrew's answer to my comment has sparked this question. According to his awesome answer in the link above, the code at the bottom of the question will only work for ONE widget. But it's killer nice code and makes sense... I guess I want the best of both worlds. Nice JS, (if that is possible) and to have the zero results show() just the element that we're using at the time. This code snippet is the main crux of my problem, as I see it: source: function (request, response) { jQuery.ajax({ url: "/autocomplete.json", data: { term: request.term }, success: function (data) { if (data.length == 0) { jQuery('span.guest_investor_email').show(); jQuery('span.investor_field_delete_button').show(); } response(data); } }); Currently: I have a button on my page that says "Add more Information" and each time you click it, a new instance of the autocomplete text field appears, complete with some hidden fields and a display:none; on guest_investor_email. If I use the autocomplete text field, say 3 times, and i have 3 autocomplete instances on the page and the third one finds 0 results: The code will show() all 3 instances of the guest_investor_email text field, instead of just this one that is blank. QUESTION: How do i get something like jQuery(this).siblings(('span.guest_investor_email').show(); to work? this is an Object and not an array of elements to select. If it isn't with this I don't mind, as long as I know how to get at it. Thanks. Full Code: jQuery(".auto_search_complete").live("click", function() { jQuery(this).autocomplete({ minLength: 3, source: function (request, response) { jQuery.ajax({ url: "/autocomplete.json", data: { term: request.term }, success: function (data) { if (data.length == 0) { jQuery('span.guest_investor_email').show(); jQuery('span.investor_field_delete_button').show(); } response(data); } }); }, focus: function(event, ui) { jQuery(this).val(ui.item.user ? ui.item.user.name : ui.item.pitch.name); return false; }, select: function(event, ui) { jQuery(this).val(ui.item.user ? ui.item.user.name : ui.item.pitch.name); jQuery(this).siblings('div.hidden_fields').children('.poly_id').val(ui.item.user ? ui.item.user.id : ui.item.pitch.id); jQuery(this).siblings('div.hidden_fields').children('.poly_type').val(ui.item.user ? "User" : "Pitch"); jQuery(this).siblings('span.guest_investor_email').hide(); jQuery(this).siblings('span.investor_field_delete_button').show(); jQuery(this).attr('readonly','readonly'); jQuery(this).attr('id', "investor-selected"); return false; } }).each(function() { jQuery(this).data( "autocomplete" )._renderItem = function( ul, item ) { return jQuery( "" ) .data( "item.autocomplete", item ) .append("" + (item.user ? item.user.name : item.pitch.name) + "" + (item.user ? item.user.investor_type : item.pitch.investor_type) + " - " + (item.user ? item.user.city : item.pitch.city) + "" ) .appendTo( ul ); }; }); });

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  • Spring @Autowired messageSource working in Controller but not in other classes?

    - by Jayaprakash
    New updates: As I could not succeed in configuring messageSource through annotations, I attempted to configure messageSource injection through servlet-context.xml. I still have messageSource as null. Please let me know if you need any more specific info, and I will provide. Thanks for your help in advance. servlet-context.xml <beans:bean id="message" class="com.mycompany.myapp.domain.common.message.Message"> <beans:property name="messageSource" ref="messageSource" /> </beans:bean> Spring gives the below information message about spring initialization. INFO : org.springframework.context.annotation.ClassPathBeanDefinitionScanner - JSR-330 'javax.inject.Named' annotation found and supported for component scanning INFO : org.springframework.beans.factory.support.DefaultListableBeanFactory - Overriding bean definition for bean 'message': replacing [Generic bean: class [com.mycompany.myapp.domain.common.message.Message]; scope=singleton; abstract=false; lazyInit=false; autowireMode=0; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=null; factoryMethodName=null; initMethodName=null; destroyMethodName=null; defined in file [C:\springsource\tc-server-developer-2.1.0.RELEASE\spring-insight-instance\wtpwebapps\myapp\WEB-INF\classes\com\mycompany\myapp\domain\common\message\Message.class]] with [Generic bean: class [com.mycompany.myapp.domain.common.message.Message]; scope=; abstract=false; lazyInit=false; autowireMode=0; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=null; factoryMethodName=null; initMethodName=null; destroyMethodName=null; defined in ServletContext resource [/WEB-INF/spring/appServlet/servlet-context.xml]] INFO : org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor - JSR-330 'javax.inject.Inject' annotation found and supported for autowiring INFO : org.springframework.beans.factory.support.DefaultListableBeanFactory - Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@1c7caac5: defining beans [org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping#0,org.springframework.format.support.FormattingConversionServiceFactoryBean#0,org.springframework.validation.beanvalidation.LocalValidatorFactoryBean#0,org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter#0,org.springframework.web.servlet.handler.MappedInterceptor#0,org.springframework.web.servlet.mvc.HttpRequestHandlerAdapter,org.springframework.web.servlet.resource.ResourceHttpRequestHandler#0,org.springframework.web.servlet.handler.SimpleUrlHandlerMapping#0,xxxDao,message,xxxService,jsonDateSerializer,xxxController,homeController,org.springframework.context.annotation.internalConfigurationAnnotationProcessor,org.springframework.context.annotation.internalAutowiredAnnotationProcessor,org.springframework.context.annotation.internalRequiredAnnotationProcessor,org.springframework.context.annotation.internalCommonAnnotationProcessor,tilesViewResolver,tilesConfigurer,messageSource,org.springframework.web.servlet.handler.MappedInterceptor#1,localeResolver,org.springframework.web.servlet.view.ContentNegotiatingViewResolver#0,validator,resourceBundleLocator,messageInterpolator]; parent: org.springframework.beans.factory.support.DefaultListableBeanFactory@4f47af3 I have the below definition for message source in 3 classes. In debug mode, I can see that in class xxxController, messageSource is initialized to org.springframework.context.support.ReloadableResourceBundleMessageSource. I have annotated Message class with @Component and xxxHibernateDaoImpl with @Repository. I also included context namespace definition in servlet-context.xml. But in Message class and xxxHibernateDaoImpl class, the messageSource is still null. Why is Spring not initializing messageSource in the two other classes though in xxxController classes, it initializes correctly? @Controller public class xxxController{ @Autowired private ReloadableResourceBundleMessageSource messageSource; } @Component public class Message{ @Autowired private ReloadableResourceBundleMessageSource messageSource; } @Repository("xxxDao") public class xxxHibernateDaoImpl{ @Autowired private ReloadableResourceBundleMessageSource messageSource; } <beans:beans xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation=" http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd"> <beans:bean id="messageSource" class="org.springframework.context.support.ReloadableResourceBundleMessageSource"> <beans:property name="basename" value="/resources/messages/messages" /> </beans:bean> <context:component-scan base-package="com.mycompany.myapp"/> </beans>

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  • Trouble with setting entry point for GWT service

    - by Xorty
    Hello. I've followed serveral tutorials and read official docs at code.google.com, but still didn't manage to resolve this thing. I am creating simple service that'll check if user can be logged. CLIENT SIDE: public interface LoginService extends RemoteService { /** * Checks, if user has valid login. * @param user User's login. * @return True if such a login is in the database. */ boolean isValidUser(User user); } And here is Async interface: public interface LoginServiceAsync { /** * Checks, if user has valid login. * @param user User's login. * @param callback the callback to return True if such a login is in the database. */ void isValidUser(User user, AsyncCallback<Boolean> callback); } SERVER SIDE: public class LoginServiceImpl extends RemoteServiceServlet implements LoginService { /** * serial version UID */ private static final long serialVersionUID = 1044980345057997696L; /**{@inheritDoc} */ @Override public boolean isValidUser(User user) { boolean success = true; //TODO change } } Now I have entry point class MailClient.java. I append here widget like: CustomWidgets.getLoginWidget(this); // access rootPanel and append widget Now I need to make actual call to my service, and here is problem: LoginServiceAsync loginService = (LoginServiceAsync) GWT.create(LoginService.class); User user = new User(boxName.getText(), boxPassword.getText()); AsyncCallback<Boolean> callback = new AsyncCallback<Boolean>() { @Override public void onFailure(Throwable caught) { Window.alert(caught.getMessage()); //TODO change } @Override public void onSuccess(Boolean result) { Window.alert("success"); //TODO change } }; ((ServiceDefTarget) loginService).setServiceEntryPoint(GWT.getModuleBaseURL()+"login"); // dunno what should be here So to recap, I don't know how to set service's entry point. Here's my MailClient.gwt.xml file: <module> <inherits name="com.google.gwt.user.User"/> <inherits name="com.google.gwt.user.theme.standard.Standard"/> <entry-point class="com.xorty.mailclient.client.MailClient"/> <servlet path="/login" class="com.xorty.mailclient.server.servlets.LoginServiceImpl" /> <inherits name="com.xorty.mailclient.MailClient"/> <inherits name="com.xorty.mailclient.MailClient"/> <inherits name="com.xorty.mailclient.MailClient"/> <inherits name="com.xorty.mailclient.MailClient"/> <inherits name="com.xorty.mailclient.MailClient"/> </module> My web.xml file: <?xml version="1.0" encoding="UTF-8"?> <web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"> <!-- Default page to serve --> <welcome-file-list> <welcome-file>MailClient.html</welcome-file> </welcome-file-list> <servlet> <servlet-name>LoginService</servlet-name> <servlet-class>com.xorty.mailclient.server.servlets.LoginServiceImpl</servlet-class> </servlet> <servlet-mapping> <servlet-name>LoginService</servlet-name> <url-pattern>/com.xorty.mailclient.MailClient/login</url-pattern> </servlet-mapping> </web-app> And here is screenshot of project structure:

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  • Algorithm to select groups of similar items in 2d array

    - by mafutrct
    There is a 2d array of items (in my case they are called Intersections). A certain item is given as a start. The task is to find all items directly or indirectly connected to this item that satisfy a certain function. So the basic algorithm is like this: Add the start to the result list. Repeat until no modification: Add each item in the array that satisfies the function and touches any item in the result list to the result list. My current implementation looks like this: private IList<Intersection> SelectGroup ( Intersection start, Func<Intersection, Intersection, bool> select) { List<Intersection> result = new List<Intersection> (); Queue<Intersection> source = new Queue<Intersection> (); source.Enqueue (start); while (source.Any ()) { var s = source.Dequeue (); result.Add (s); foreach (var neighbour in Neighbours (s)) { if (select (start, neighbour) && !result.Contains (neighbour) && !source.Contains (neighbour)) { source.Enqueue (neighbour); } } } Debug.Assert (result.Distinct ().Count () == result.Count ()); Debug.Assert (result.All (x => select (x, result.First ()))); return result; } private List<Intersection> Neighbours (IIntersection intersection) { int x = intersection.X; int y = intersection.Y; List<Intersection> list = new List<Intersection> (); if (x > 1) { list.Add (GetIntersection (x - 1, y)); } if (y > 1) { list.Add (GetIntersection (x, y - 1)); } if (x < Size) { list.Add (GetIntersection (x + 1, y)); } if (y < Size) { list.Add (GetIntersection (x, y + 1)); } return list; } (The select function takes a start item and returns true iff the second item satisfies.) This does its job and turned out to be reasonable fast for the usual array sizes (about 20*20). However, I'm interested in further improvements. Any ideas? Example (X satisfies in relation to other Xs, . does never satisfy): .... XX.. .XX. X... In this case, there are 2 groups: a central group of 4 items and a group of a single item in the lower left. Selecting the group (for instance by starting item [2, 2]) returns the former, while the latter can be selected using the starting item and sole return value [0, 3]. Example 2: .A.. ..BB A.AA This time there are 4 groups. The 3 A groups are not connected, so they are returned as separate groups. The bigger A and B groups are connected, but A does not related to B so they are returned as separate groups.

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  • New cast exception with VS2010/.Net 4

    - by Trevor
    [ Updated 25 May 2010 ] I've recently upgraded from VS2008 to VS2010, and at the same time upgraded to .Net 4. I've recompiled an existing solution of mine and I'm encountering a Cast exception I did not have before. The structure of the code is simple (although the actual implementation somewhat more complicated). Basically I have: public class SomeClass : ISomeClass { // Stuff } public static class ClassFactory { public static IInterface GetClassInstance<IInterface>(Type classType) { return (IInterface)Activator.CreateInstance(classType); // This throws a cast exception } } // Call the factory with: ISomeClass anInstance = ClassFactory.GetClassInstance<ISomeClass>(typeof(SomeClass)); Ignore the 'sensibleness' of the above - its provides just a representation of the issue rather than the specifics of what I'm doing (e.g. constructor parameters have been removed). The marked line throws the exception: Unable to cast object of type 'Namespace.SomeClass' to type 'Namespace.ISomeClass'. I suspect it may have something to do with the additional DotNet security (and in particular, explicit loading of assemblies, as this is something my app does). The reason I suspect this is that I have had to add to the config file the setting: <runtime> <loadFromRemoteSources enabled="true" /> </runtime> .. but I'm unsure if this is related. Update I see (from comments) that my basic code does not reproduce the issue by itself. Not surprising I suppose. It's going to be tricky to identify which part of a largish 3-tier CQS system is relevant to this problem. One issue might be that there are multiple assemblies involved. My static class is actually a factory provider, and the 'SomeClass' is a class factory (relevant in that the factories are 'registered' within the app via explicit assembly/type loading - see below) . Upfront I use reflection to 'register' all factories (i.e. classes that implement a particular interface) and that I do this when the app starts by identifying the relevant assemblies, loading them and adding them to a cache using (in essence): Loop over (file in files) { Assembly assembly = Assembly.LoadFile(file); baseAssemblyList.Add(assembly); } Then I cache the available types in these assemblies with: foreach (Assembly assembly in _loadedAssemblyList) { Type[] assemblyTypes = assembly.GetTypes(); _loadedTypesCache.AddRange(assemblyTypes); } And then I use this cache to do a variety of reflection operations, including 'registering' of factories, which involves looping through all loaded (cached) types and finding those that implement the (base) Factory interface. I've experienced what may be a similar problem in the past (.Net 3.5, so not exactly the same) with an architecture that involved dynamically creating classes on the server and streaming the compiled binary of those classes to the client app. The problem came when trying to deserialize an instance of the dynamic class on the client from a remote call: the exception said the class type was not know, even though the source and destination types were exactly the same name (including namespace). Basically the cross boundry versions of the class were not recognised as being the same. I solved that by intercepting the deserialization process and explicitly defining the deseriazation class type in the context of the local assemblies. This experience is what makes me think the types are considered mismatched because (somehow) the interface of the actual SomeClass object, and the interface of passed into the Generic method are not considered the same type. So (possibly) my question for those more knowledgable about C#/DotNet is: How does the class loading work that somehow my app thinks there are two versions/types of the interface type and how can I fit that? [ whew ... anyone who got here is quite patient .. thanks ]

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  • Explicit method tables in C# instead of OO - good? bad?

    - by FunctorSalad
    Hi! I hope the title doesn't sound too subjective; I absolutely do not mean to start a debate on OO in general. I'd merely like to discuss the basic pros and cons for different ways of solving the following sort of problem. Let's take this minimal example: you want to express an abstract datatype T with functions that may take T as input, output, or both: f1 : Takes a T, returns an int f2 : Takes a string, returns a T f3 : Takes a T and a double, returns another T I'd like to avoid downcasting and any other dynamic typing. I'd also like to avoid mutation whenever possible. 1: Abstract-class-based attempt abstract class T { abstract int f1(); // We can't have abstract constructors, so the best we can do, as I see it, is: abstract void f2(string s); // The convention would be that you'd replace calls to the original f2 by invocation of the nullary constructor of the implementing type, followed by invocation of f2. f2 would need to have side-effects to be of any use. // f3 is a problem too: abstract T f3(double d); // This doesn't express that the return value is of the *same* type as the object whose method is invoked; it just expresses that the return value is *some* T. } 2: Parametric polymorphism and an auxilliary class (all implementing classes of TImpl will be singleton classes): abstract class TImpl<T> { abstract int f1(T t); abstract T f2(string s); abstract T f3(T t, double d); } We no longer express that some concrete type actually implements our original spec -- an implementation is simply a type Foo for which we happen to have an instance of TImpl. This doesn't seem to be a problem: If you want a function that works on arbitrary implementations, you just do something like: // Say we want to return a Bar given an arbitrary implementation of our abstract type Bar bar<T>(TImpl<T> ti, T t); At this point, one might as well skip inheritance and singletons altogether and use a 3 First-class function table class /* or struct, even */ TDictT<T> { readonly Func<T,int> f1; readonly Func<string,T> f2; readonly Func<T,double,T> f3; TDict( ... ) { this.f1 = f1; this.f2 = f2; this.f3 = f3; } } Bar bar<T>(TDict<T> td; T t); Though I don't see much practical difference between #2 and #3. Example Implementation class MyT { /* raw data structure goes here; this class needn't have any methods */ } // It doesn't matter where we put the following; could be a static method of MyT, or some static class collecting dictionaries static readonly TDict<MyT> MyTDict = new TDict<MyT>( (t) => /* body of f1 goes here */ , // f2 (s) => /* body of f2 goes here */, // f3 (t,d) => /* body of f3 goes here */ ); Thoughts? #3 is unidiomatic, but it seems rather safe and clean. One question is whether there are any performance concerns with it. I don't usually need dynamic dispatch, and I'd prefer if these function bodies get statically inlined in places where the concrete implementing type is known statically. Is #2 better in that regard?

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  • Concurrency and Calendar classes

    - by fbielejec
    I have a thread (class implementing runnable, called AnalyzeTree) organised around a hash map (ConcurrentMap slicesMap). The class goes through the data (called trees here) in the large text file and parses the geographical coordinates from it to the HashMap. The idea is to process one tree at a time and add or grow the values according to the key (which is just a Double value representing time). The relevant part of code looks like this: // grow map entry if key exists if (slicesMap.containsKey(sliceTime)) { double[] imputedLocation = imputeValue( location, parentLocation, sliceHeight, nodeHeight, parentHeight, rate, useTrueNoise, currentTreeNormalization, precisionArray); slicesMap.get(sliceTime).add( new Coordinates(imputedLocation[1], imputedLocation[0], 0.0)); // start new entry if no such key in the map } else { List<Coordinates> coords = new ArrayList<Coordinates>(); double[] imputedLocation = imputeValue( location, parentLocation, sliceHeight, nodeHeight, parentHeight, rate, useTrueNoise, currentTreeNormalization, precisionArray); coords.add(new Coordinates(imputedLocation[1], imputedLocation[0], 0.0)); slicesMap.putIfAbsent(sliceTime, coords); // slicesMap.put(sliceTime, coords); }// END: key check And the class is called like this (executor is ExecutorService executor = Executors.newFixedThreadPool(NTHREDS) ): mrsd = new SpreadDate(mrsdString); int readTrees = 1; while (treesImporter.hasTree()) { currentTree = (RootedTree) treesImporter.importNextTree(); executor.submit(new AnalyzeTree(currentTree, precisionString, coordinatesName, rateString, numberOfIntervals, treeRootHeight, timescaler, mrsd, slicesMap, useTrueNoise)); // new AnalyzeTree(currentTree, precisionString, // coordinatesName, rateString, numberOfIntervals, // treeRootHeight, timescaler, mrsd, slicesMap, // useTrueNoise).run(); readTrees++; }// END: while has trees Now this is running into troubles when executed in parallel (the commented part running sequentially is fine), I thought it might throw a ConcurrentModificationException, but apparently the problem is in mrsd (instance of SpreadDate object, which is simply a class for date related calculations). The SpreadDate class looks like this: public class SpreadDate { private Calendar cal; private SimpleDateFormat formatter; private Date stringdate; public SpreadDate(String date) throws ParseException { // if no era specified assume current era String line[] = date.split(" "); if (line.length == 1) { StringBuilder properDateStringBuilder = new StringBuilder(); date = properDateStringBuilder.append(date).append(" AD") .toString(); } formatter = new SimpleDateFormat("yyyy-MM-dd G", Locale.US); stringdate = formatter.parse(date); cal = Calendar.getInstance(); } public long plus(int days) { cal.setTime(stringdate); cal.add(Calendar.DATE, days); return cal.getTimeInMillis(); }// END: plus public long minus(int days) { cal.setTime(stringdate); cal.add(Calendar.DATE, -days); //line 39 return cal.getTimeInMillis(); }// END: minus public long getTime() { cal.setTime(stringdate); return cal.getTimeInMillis(); }// END: getDate } And the stack trace from when exception is thrown: java.lang.ArrayIndexOutOfBoundsException: 58 at sun.util.calendar.BaseCalendar.getCalendarDateFromFixedDate(BaseCalendar.java:454) at java.util.GregorianCalendar.computeFields(GregorianCalendar.java:2098) at java.util.GregorianCalendar.computeFields(GregorianCalendar.java:2013) at java.util.Calendar.setTimeInMillis(Calendar.java:1126) at java.util.GregorianCalendar.add(GregorianCalendar.java:1020) at utils.SpreadDate.minus(SpreadDate.java:39) at templates.AnalyzeTree.run(AnalyzeTree.java:88) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334) at java.util.concurrent.FutureTask.run(FutureTask.java:166) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603) at java.lang.Thread.run(Thread.java:636) If a move the part initializing mrsd to the AnalyzeTree class it runs without any problems - however it is not very memory efficient to initialize class each time this thread is running, hence my concerns. How can it be remedied?

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  • web application with secured sections, sessions and related trouble

    - by spirytus
    I would like to create web application with admin/checkout sections being secured. Assuming I have SSL set up for subdomain.mydomain.com I would like to make sure that all that top-secret stuff ;) like checkout pages and admin section is transferred securely. Would it be ok to structure my application as below? subdomain.mydomain.com adminSectionFolder adminPage1.php adminPage2.php checkoutPagesFolder checkoutPage1.php checkoutPage2.php checkoutPage3.php homepage.php loginPage.php someOtherPage.php someNonSecureFolder nonSecurePage1.php nonSecurePage2.php nonSecurePage3.php imagesFolder image1.jpg image2.jpg image3.jpg Users would access my web application via http as there is no need for SSL for homepage and similar. Checkout/admin pages would have to be accessed via https though (that I would ensure via .htaccess redirects). I would also like to have login form on every page of the site, including non-secure pages. Now my questions are: if I have form on non-secure page e.g http://subdomain.mydomain.com/homepage.php and that form sends data to http://subdomain.mydomain.com/loginPage.php, is data being send encrypted as if it were sent from https://subdomain.mydomain.com/homepage.php? I do realize users will not see padlock, but browser still should encrypt it, is it right? If on secure page loginPage.php (or any other accessed via https for that instance) I created session, session ID would be assigned, and in case of my web app. something like username of the logged in user. Would I be able to access these session variable from http://subdomain.mydomain.com/homepage.php to for example display greeting message? If session ID is stored in cookies then it would be trouble I assume, but could someone clarify how it should be done? It seems important to have username and password send over SSL. Related to above question I think.. would it actually make any sense to have login secured via SSL so usenrame/password would be transferred securely, and then session ID being transferred with no SSL? I mean wouldnt it be the same really if someone caught username and password being transferred, or caught session ID? Please let me know if I make sense here cause it feels like I'm missing something important. EDIT: I came up with idea but again please let me know if that would work. Having above, so assuming that sharing session between http and https is as secure as login in user via plain http (not https), I guess on all non secure pages, like homepage etc. I could check if user is already logged in, and if so from php redirect to https version of same page. So user fills in login form from homepage.php, over ssl details are send to backend so probably https://.../homepage.php. Trying to access http://.../someOtherPage.php script would always check if session is created and if so redirect user to https version of this page so https://.../someOtherPage.php. Would that work? 4.To avoid browser popping message "this page contains non secure items..." my links to css, images and all assets, e.g. in case of http://subdomain.mydomain.com/checkoutPage1.php should be absolute so "/images/image1.jpg" or relative so "../images/image1.jpg"? I guess one of those would have to work :) wow that's long post, thanks for your patience if you got that far and any answers :) oh yeh and I use php/apache on shared hosting

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  • Winforms controls and "generic" events handlers. How can I do this?

    - by Yanko Hernández Alvarez
    In the demo of the ObjectListView control there is this code (in the "Complex Example" tab page) to allow for a custom editor (a ComboBox) (Adapted to my case and edited for clarity): EventHandler CurrentEH; private void ObjectListView_CellEditStarting(object sender, CellEditEventArgs e) { if (e.Column == SomeCol) { ISomeInterface M = (e.RowObject as ObjectListView1Row).SomeObject; //(1) ComboBox cb = new ComboBox(); cb.Bounds = e.CellBounds; cb.DropDownStyle = ComboBoxStyle.DropDownList; cb.DataSource = ISomeOtherObjectCollection; cb.DisplayMember = "propertyName"; cb.DataBindings.Add("SelectedItem", M, "ISomeOtherObject", false, DataSourceUpdateMode.Never); e.Control = cb; cb.SelectedIndexChanged += CurrentEH = (object sender2, EventArgs e2) => M.ISomeOtherObject = (ISomeOtherObject)((ComboBox)sender2).SelectedValue; //(2) } } private void ObjectListView_CellEditFinishing(object sender, CellEditEventArgs e) { if (e.Column == SomeCol) { // Stop listening for change events ((ComboBox)e.Control).SelectedIndexChanged -= CurrentEH; // Any updating will have been down in the SelectedIndexChanged // event handler. // Here we simply make the list redraw the involved ListViewItem ((ObjectListView)sender).RefreshItem(e.ListViewItem); // We have updated the model object, so we cancel the auto update e.Cancel = true; } } I have too many other columns with combo editors inside objectlistviews to use a copy& paste strategy (besides, copy&paste is a serious source of bugs), so I tried to parameterize the code to keep the code duplication to a minimum. ObjectListView_CellEditFinishing is a piece of cake: HashSet<OLVColumn> cbColumns = new HashSet<OLVColumn> (new OLVColumn[] { SomeCol, SomeCol2, ...}; private void ObjectListView_CellEditFinishing(object sender, CellEditEventArgs e) { if (cbColumns.Contains(e.Column)) ... but ObjectListView_CellEditStarting is the problematic. I guess in CellEditStarting I will have to discriminate each case separately: private void ObjectListView_CellEditStarting(object sender, CellEditEventArgs e) { if (e.Column == SomeCol) // code to create the combo, put the correct list as the datasource, etc. else if (e.Column == SomeOtherCol) // code to create the combo, put the correct list as the datasource, etc. And so on. But how can I parameterize the "code to create the combo, put the correct list as the datasource, etc."? Problem lines are (1) Get SomeObject. the property NAME varies. (2) Set ISomeOtherObject, the property name varies too. The types vary too, but I can cover those cases with a generic method combined with a not so "typesafe" API (for instance, the cb.DataBindings.Add and cb.DataSource both use an object) Reflection? more lambdas? Any ideas? Any other way to do the same? PS: I want to be able to do something like this: private void ObjectListView_CellEditStarting(object sender, CellEditEventArgs e) { if (e.Column == SomeCol) SetUpCombo<ISomeInterface>(ISomeOtherObjectCollection, "propertyName", SomeObject, ISomeOtherObject); else if (e.Column == SomeOtherCol) SetUpCombo<ISomeInterface2>(ISomeOtherObject2Collection, "propertyName2", SomeObject2 ISomeOtherObject2); and so on. Or something like that. I know, parameters SomeObject and ISomeOtherObject are not real parameters per see, but you get the idea of what I want. I want not to repeat the same code skeleton again and again and again. One solution would be "preprocessor generics" like C's DEFINE, but I don't thing c# has something like that. So, does anyone have some alternate ideas to solve this?

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  • fetching rss feed, mktime problem (wordpress plugin)

    - by krike
    sorry for the weird question but actually I'm not sure how to ask this. the code works fine but the problem is the following. I fetch items from feeds and compare them to a specific date which is stored into the database as an option. I see if the fetched item is more recent or not and if it is I create a new pending post. however there is one item that just keeps being added because there is something wrong with the date and I don't understand what is wrong because all other items (before and after) are blocked once they are being added as post (so when they are not recent anymore compared with the date I store as an option) I then echo'ed that line and this is the result: yes it exist! 27-03-2010-04-03 Free Exclusive Vector Icon Pack: Web User Interface 29-01-2010-03-01 if(1330732800 < 1335830400) 01 05 2012 the first line is to see if the option still exist and what data was stored in it the second is the actual items that's causing all the problem, it's initial date is less recent then the date but still passes as more recent.... this is the code I use, any help would be great: if(!get_option('feed_last_date')): echo "nope doesn't exist, but were creating one"; $time = time()-60*60*24*30*3; add_option("feed_last_date", date('d-m-Y-h-m', $time)); else: echo "yes it exist! ".get_option('feed_last_date'); endif; //Create new instance of simple pie and pass in feed link $feed = new SimplePie($feeds); //Call function handle_content_type() $feed->handle_content_type(); $last_date = explode("-", get_option('feed_last_date')); $day = $last_date[0]; $month = $last_date[1]; $year = $last_date[2]; $hour = $last_date[3]; $minute = $last_date[4]; $last_date = mktime(0,0,0, $day, $month, $year); //4 - Loop through received items foreach($feed->get_items(0, 500) as $item) : $feed_date = explode("-", $item->get_date('d-m-Y-h-m')); $day = $feed_date[0]; $month = $feed_date[1]; $year = $feed_date[2]; $hour = $feed_date[3]; $minute = $feed_date[4]; $feed_date = mktime(0,0,0,$day, $month, $year); if($last_date < $feed_date): echo $item->get_title()." ". $item->get_date('d-m-Y-h-m') ." if(".$last_date." < ".$feed_date.") <b>".date("d m Y", $feed_date)."</b><br />"; //if datum is newer then stored in database, then create new post $description = "<h3>download the resource</h3><p><a href='".$item->get_permalink()."' target='_blank'>".$item->get_permalink()."</a></p><h3>Resource description</h3><p>".$item->get_description()."</p>"; $new_post = array( 'post_title' => $item->get_title(), 'post_content' => $description, 'post_status' => 'pending', 'post_date' => date('Y-m-d H:i:s'), 'post_author' => $user_ID, 'post_type' => 'post', 'post_category' => array(0) ); $post_id = wp_insert_post($new_post); endif; endforeach; update_option("feed_last_date", date('d-m-Y-h-m', time()));

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  • Spring MVC application - URL gives No file found (404)

    - by user1700184
    I created a Spring-MVC project. web.xml: <servlet> <servlet-name>mvc-dispatcher</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>mvc-dispatcher</servlet-name> <url-pattern>/soundmails</url-pattern> </servlet-mapping> mvc-dispatcher-servlet.xml <?xml version="1.0"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd"> <mvc:annotation-driven /> <context:component-scan base-package="somepkg.controllers" /> <bean id="multipartResolver" class="org.gmr.web.multipart.GMultipartResolver"> <property name="maxUploadSize" value="1048576" /> </bean> <bean id="placeholderConfig" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <!-- property name="location"> <value>/WEB-INF/social.properties</value> </property--> </bean> <bean id="jacksonMessageConverter" class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"></bean> <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"> <property name="messageConverters"> <list> <ref bean="jacksonMessageConverter"/> </list> </property> </bean> </beans> The controller has this code: ProjectController.java @Controller @RequestMapping("/soundmails") public class FileUploadController { @RequestMapping(value="/test", method=RequestMethod.GET) public @ResponseBody String test() { System.out.println("Hai"); return "Hai"; } } I am using Google App Engine in my local machine to test this. I am getting these in my log: [INFO] Oct 24, 2013 1:54:18 AM com.google.appengine.tools.development.LocalResourceFileServlet doGet [INFO] WARNING: No file found for: /soundmails/test I tried /soundmails/soundmails/test as well. That is also giving the same error. I am using Spring 3.1.0.RELEASE Can someone help me figure out what I am missing - /soundmails/test is giving 404 error. Edit I am unable to enable DEBUG logs for this. For some reason, it is not taking log level configured in logging.properties But I observed something interesting: 1) If I map the request to empty string (value = "") @RequestMapping(value="", method=RequestMethod.GET) public @ResponseBody String test() { System.out.println("Hai"); return "Hai"; } Then, when I try to access 127.0.0.1/soundmails, it works fine (returns string "Hai"). 2) When I have value="/test" @RequestMapping(value="/test", method=RequestMethod.GET) public @ResponseBody String test() { System.out.println("Hai"); return "Hai"; } and I try to access 127.0.0.1/soundmails/test, it is giving HTTP 404. This is weird.

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  • Many-to-many mapping with LINQ

    - by Alexander
    I would like to perform LINQ to SQL mapping in C#, in a many-to-many relationship, but where data is not mandatory. To be clear: I have a news site/blog, and there's a table called Posts. A blog can relate to many categories at once, so there is a table called CategoriesPosts that links with foreign keys with the Posts table and with Categories table. I've made each table with an identity primary key, an id field in each one, if it matters in this case. In C# I defined a class for each table, defined each field as explicitly as possible. The Post class, as well as Category class, have a EntitySet to link to CategoryPost objects, and CategoryPost class has 2 EntityRef members to link to 2 objects of each other type. The problem is that a Post may relate or not to any category, as well as a category may have posts in it or not. I didn't find a way to make an EntitySet<CategoryPost?> or something like that. So when I added the first post, all went well with not a single SQL statement. Also, this post was present in the output. When I tried to add the second post I got an exception, Object reference not set to an instance of an object, regarding to the CategoryPost member. Post: [Table(Name="tm_posts")] public class Post : IDataErrorInfo { public Post() { //Initialization of NOT NULL fields with their default values } [Column(Name = "id", DbType = "int", CanBeNull = false, IsDbGenerated = true, IsPrimaryKey = true)] public int ID { get; set; } private EntitySet<CategoryPost> _categoryRef = new EntitySet<CategoryPost>(); [Association(Name = "tm_rel_categories_posts_fk2", IsForeignKey = true, Storage = "_categoryRef", ThisKey = "ID", OtherKey = "PostID")] public EntitySet<CategoryPost> CategoryRef { get { return _categoryRef; } set { _categoryRef.Assign(value); } } } CategoryPost [Table(Name = "tm_rel_categories_posts")] public class CategoryPost { [Column(Name = "id", DbType = "int", CanBeNull = false, IsDbGenerated = true, IsPrimaryKey = true)] public int ID { get; set; } [Column(Name = "fk_post", DbType = "int", CanBeNull = false)] public int PostID { get; set; } [Column(Name = "fk_category", DbType = "int", CanBeNull = false)] public int CategoryID { get; set; } private EntityRef<Post> _post = new EntityRef<Post>(); [Association(Name = "tm_rel_categories_posts_fk2", IsForeignKey = true, Storage = "_post", ThisKey = "PostID", OtherKey = "ID")] public Post Post { get { return _post.Entity; } set { _post.Entity = value; } } private EntityRef<Category> _category = new EntityRef<Category>(); [Association(Name = "tm_rel_categories_posts_fk", IsForeignKey = true, Storage = "_category", ThisKey = "CategoryID", OtherKey = "ID")] public Category Category { get { return _category.Entity; } set { _category.Entity = value; } } } Category [Table(Name="tm_categories")] public class Category { [Column(Name = "id", DbType = "int", CanBeNull = false, IsDbGenerated = true, IsPrimaryKey = true)] public int ID { get; set; } [Column(Name = "fk_parent", DbType = "int", CanBeNull = true)] public int ParentID { get; set; } private EntityRef<Category> _parent = new EntityRef<Category>(); [Association(Name = "tm_posts_fk2", IsForeignKey = true, Storage = "_parent", ThisKey = "ParentID", OtherKey = "ID")] public Category Parent { get { return _parent.Entity; } set { _parent.Entity = value; } } [Column(Name = "name", DbType = "varchar(100)", CanBeNull = false)] public string Name { get; set; } } So what am I doing wrong? How to make it possible to insert a post that doesn't belong to any category? How to insert categories with no posts?

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  • iPhone NSCalendar - Incorrect Calendar Drawn for users outside US

    - by xoail
    After trying to work on someone else's code, and so many different iterations, I am unable to understand what am I doing wrong with dates on a calendar month view. I am trying to present a calendar in month view fashion like calendar.app but unfortunately some users in countries like Australia, UK are reporting incorrect alignment of Days to Dates. For instance in Australia it displays 17th March as Friday. Any help is highly appreciated! Here is the code sample I am using: -(void)setCalendar { NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar]; NSDateComponents *comps = [gregorian components:units fromDate:[NSDate date]]; self.currentDate = [gregorian dateFromComponents:comps]; NSInteger weekdayInteger=[comps weekday]; currentMonth=[comps month]; currentYear=[comps year]; NSString *dateString=[[NSString stringWithFormat:@"%@",currentDate] substringToIndex:10]; NSArray *array= [dateString componentsSeparatedByString:@"-"]; NSInteger currentDay=[[array objectAtIndex:2] intValue]; currentMonthConstant=currentMonth; currentYearConstant=currentYear; currentDayConstant=currentDay; currentConstantDate=[NSString stringWithFormat:@"%d/%d/%d",currentDayConstant,currentMonthConstant,currentYearConstant]; currentFirstDay=((8+weekdayInteger-(currentDay%7))%7); if(currentFirstDay==0) currentFirstDay=7; [gregorian release]; } And this is how im populating the calendar: -(void)fillCalender:(NSInteger)month weekStarts:(NSInteger)weekday year:(NSInteger)year { currentMonth=month; currentYear=year; currentFirstDay=weekday; UIButton *temp; NSInteger numberOfDays=[self getNumberofDays:month YearVlue:year]; currentLastDay=(currentFirstDay+numberOfDays-1)%7; if(currentLastDay==0) currentLastDay=7; NSString *monthName=[self getMonth:month]; NSInteger grid=(weekday-1); monthLabel.text=[NSString stringWithFormat:@"%@ %d",monthName,year]; for(int i=1;i<=numberOfDays;i++) { if([frontView isEqualToString:@"view1"]) temp=[arr_View2Buttons objectAtIndex:grid]; else temp= [arr_View1Buttons objectAtIndex:grid]; [temp setBackgroundImage:nil forState:UIControlStateNormal]; [temp setUserInteractionEnabled:TRUE]; UILabel *aLbl = (UILabel *)[temp viewWithTag:123]; [aLbl setText:[NSString stringWithFormat:@"%d",i]]; // check for today if(currentDayConstant == i && currentMonthConstant == currentMonth && currentYearConstant == currentYear) { [aLbl setTextColor:[UIColor blueColor]]; } else { [aLbl setTextColor:[UIColor colorWithRed:69/255.0 green:2/255.0 blue:71/255.0 alpha:1.0]]; } [temp setTag:i]; grid++; if(grid==35) grid=0; } } And finally viewdidload: - (void)viewDidLoad { [super viewDidLoad]; [self setCalendar]; // set views [self.view1 setFrame:CGRectMake(0,45,320,232)]; [self.view2 setFrame:CGRectMake(0,277,320,232)]; [self.view addSubview:self.view1]; [self.view addSubview:self.view2]; frontView = @"view2"; [self fillCalender:currentMonth weekStarts:currentFirstDay year:currentYear]; frontView = @"view1"; }

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  • Make interchangeable class types via pointer casting only, without having to allocate any new objects?

    - by HostileFork
    UPDATE: I do appreciate "don't want that, want this instead" suggestions. They are useful, especially when provided in context of the motivating scenario. Still...regardless of goodness/badness, I've become curious to find a hard-and-fast "yes that can be done legally in C++11" vs "no it is not possible to do something like that". I want to "alias" an object pointer as another type, for the sole purpose of adding some helper methods. The alias cannot add data members to the underlying class (in fact, the more I can prevent that from happening the better!) All aliases are equally applicable to any object of this type...it's just helpful if the type system can hint which alias is likely the most appropriate. There should be no information about any specific alias that is ever encoded in the underlying object. Hence, I feel like you should be able to "cheat" the type system and just let it be an annotation...checked at compile time, but ultimately irrelevant to the runtime casting. Something along these lines: Node<AccessorFoo>* fooPtr = Node<AccessorFoo>::createViaFactory(); Node<AccessorBar>* barPtr = reinterpret_cast< Node<AccessorBar>* >(fooPtr); Under the hood, the factory method is actually making a NodeBase class, and then using a similar reinterpret_cast to return it as a Node<AccessorFoo>*. The easy way to avoid this is to make these lightweight classes that wrap nodes and are passed around by value. Thus you don't need casting, just Accessor classes that take the node handle to wrap in their constructor: AccessorFoo foo (NodeBase::createViaFactory()); AccessorBar bar (foo.getNode()); But if I don't have to pay for all that, I don't want to. That would involve--for instance--making a special accessor type for each sort of wrapped pointer (AccessorFooShared, AccessorFooUnique, AccessorFooWeak, etc.) Having these typed pointers being aliased for one single pointer-based object identity is preferable, and provides a nice orthogonality. So back to that original question: Node<AccessorFoo>* fooPtr = Node<AccessorFoo>::createViaFactory(); Node<AccessorBar>* barPtr = reinterpret_cast< Node<AccessorBar>* >(fooPtr); Seems like there would be some way to do this that might be ugly but not "break the rules". According to ISO14882:2011(e) 5.2.10-7: An object pointer can be explicitly converted to an object pointer of a different type.70 When a prvalue v of type "pointer to T1" is converted to the type "pointer to cv T2", the result is static_cast(static_cast(v)) if both T1 and T2 are standard-layout types (3.9) and the alignment requirements of T2 are no stricter than those of T1, or if either type is void. Converting a prvalue of type "pointer to T1" to the type "pointer to T2" (where T1 and T2 are object types and where the alignment requirements of T2 are no stricter than those of T1) and back to its original type yields the original pointer value. The result of any other such pointer conversion is unspecified. Drilling into the definition of a "standard-layout class", we find: has no non-static data members of type non-standard-layout-class (or array of such types) or reference, and has no virtual functions (10.3) and no virtual base classes (10.1), and has the same access control (clause 11) for all non-static data members, and has no non-standard-layout base classes, and either has no non-static data member in the most-derived class and at most one base class with non-static data members, or has no base classes with non-static data members, and has no base classes of the same type as the first non-static data member. Sounds like working with something like this would tie my hands a bit with no virtual methods in the accessors or the node. Yet C++11 apparently has std::is_standard_layout to keep things checked. Can this be done safely? Appears to work in gcc-4.7, but I'd like to be sure I'm not invoking undefined behavior.

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