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  • How to place images on top of each other in java

    - by Haxed
    Hi, I have a background image of a road, which I have displayed on a JFrame using an ImageIcon. I want to put a car on top of that background image at a certain (x,y) location. I tried using another ImageIcon and the background does not appear when I run the program , however the car does. import javax.swing.ImageIcon; import javax.swing.JFrame; import javax.swing.JLabel; public class Gui extends JFrame { private ImageIcon northcar = new ImageIcon("src/north.gif"); private ImageIcon usIcon = new ImageIcon("src/trafficLight.jpg"); public Gui() { add(new JLabel(usIcon)); // background image does not appear after the i added the northcar label add(new JLabel(northcar)); // this picture can be seen } public static void main(String[] args) { Gui frame = new Gui(); frame.setTitle("TestImageIcon"); frame.setLocationRelativeTo(null); // Center the frame frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setBounds(0, 0, 650, 650); frame.setVisible(true); } } I heard about using a canvas but have no clue. Any ideas ? Many Thanks

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  • How to specify allowed exceptions in WCF's configuration file?

    - by tucaz
    Hello! I´m building a set of WCF services for internal use through all our applications. For exception handling I created a default fault class so I can return treated message to the caller if its the case or a generic one when I have no clue what happened. Fault contract: [DataContract(Name = "DefaultFault", Namespace = "http://fnac.com.br/api/2010/03")] public class DefaultFault { public DefaultFault(DefaultFaultItem[] items) { if (items == null || items.Length== 0) { throw new ArgumentNullException("items"); } StringBuilder sbItems = new StringBuilder(); for (int i = 0; i Specifying that my method can throw this exception so the consuming client will be aware of it: [OperationContract(Name = "PlaceOrder")] [FaultContract(typeof(DefaultFault))] [WebInvoke(UriTemplate = "/orders", BodyStyle = WebMessageBodyStyle.Bare, ResponseFormat = WebMessageFormat.Json, RequestFormat = WebMessageFormat.Json, Method = "POST")] string PlaceOrder(Order newOrder); Most of time we will use just .NET to .NET communication with usual binds and everything works fine since we are talking the same language. However, as you can see in the service contract declaration I have a WebInvoke attribute (and a webHttp binding) in order to be able to also talk JSON since one of our apps will be built for iPhone and this guy will talk JSON. My problem is that whenever I throw a FaultException and have includeExceptionDetails="false" in the config file the calling client will get a generic HTTP error instead of my custom message. I understand that this is the correct behavior when includeExceptionDetails is turned off, but I think I saw some configuration a long time ago to allow some exceptions/faults to pass through the service boundaries. Is there such thing like this? If not, what do u suggest for my case? Thanks a LOT!

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  • Spring MessageSource not being used during validation

    - by Jeremy
    I can't get my messages in messages.properties to be used during Spring validation of my form backing objects. app-config.xml: <bean id="messageSource" class="org.springframework.context.support.ResourceBundleMessageSource"> <property name="basename" value="messages" /> </bean> WEB-INF/classes/messages.properties: NotEmpty=This field should not be empty. Form Backing Object: ... @NotEmpty @Size(min=6, max=25) private String password; ... When I loop through all errors in the BindingResult and output the ObjectError's toString I get this: Field error in object 'settingsForm' on field 'password': rejected value []; codes [NotEmpty.settingsForm.password,NotEmpty.password,NotEmpty.java.lang.String,NotEmpty]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [settingsForm.password,password]; arguments []; default message [password]]; default message [may not be empty] As you can see the default message is "may not be empty" instead of my message "This field should not be empty". I do get my correct message if I inject the messageSource into a controller and output this: messageSource.getMessage("NotEmpty", new Object [] {"password"}, "default empty message", null); So why isn't the validation using my messages.properties? I'm running Spring 3.1.1. Thanks!

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  • Android app crashes on Async Task

    - by Telmo Vaz
    why is my APP crashing when I invoke the AsyncTask? public class Login extends Activity { String mail; EditText mailIn; Button btSubmit; @Override protected void onCreate(Bundle tokenArg) { super.onCreate(tokenArg); setContentView(R.layout.login); mailIn = (EditText)findViewById(R.id.usermail); btSubmit = (Button)findViewById(R.id.submit); btSubmit.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View thisView) { new LoginProc().execute(); } }); } public class LoginProc extends AsyncTask<String, Void, Void> { @Override protected void onPreExecute() { mailIn = (EditText)findViewById(R.id.usermail); mail = mailIn.getText().toString(); super.onPreExecute(); } @Override protected Void doInBackground(String... params) { Toast.makeText(getApplicationContext(), mail, Toast.LENGTH_SHORT).show(); return null; } } } I'm trying to make the String name get it's value on the preExecute method, but it happens that the app crashes on that point. Even if I take the preExecute and do that on the doInBrackground, it still crashes. What's wrong?

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  • ASP.NET MVC: Can't figure out what VirtualPath is?

    - by Ryan_Pitts
    I have a View that displays a list of images and i am now trying to get it to display the images as thumbnails. Well, i'm pretty sure i got most of it right using VirtualPath's from a custom ActionResult although i can't seem to figure out what it is making the VirtualPath url?? BTW, i'm using XML to store the data from the images instead of SQL. Here is my code: Code from my custom ActionResult: public class ThumbnailResult : ActionResult { public ThumbnailResult(string virtualPath) { this.VirtualPath = virtualPath; } public string VirtualPath { get; set; } public override void ExecuteResult(ControllerContext context) { context.HttpContext.Response.ContentType = "image/bmp"; string fullFileName = context.HttpContext.Server.MapPath("~/Galleries/WhereConfusionMeetsConcrete/" + VirtualPath); using (System.Drawing.Image photoImg = System.Drawing.Image.FromFile(fullFileName)) { using (System.Drawing.Image thumbPhoto = photoImg.GetThumbnailImage(100, 100, null, new System.IntPtr())) { using (System.IO.MemoryStream ms = new System.IO.MemoryStream()) { thumbPhoto.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg); context.HttpContext.Response.BinaryWrite(ms.ToArray()); context.HttpContext.Response.End(); } } } } } Code for my Controller: public ActionResult Thumbnail(string id) { return new ThumbnailResult(id); } Code for my View: <% foreach (var image in ViewData.Model) { %> <a href="../Galleries/TestGallery1/<%= image.Path %>"><img src="../Galleries/TestGallery1/thumbnail/<%= image.Path %>" alt="<%= image.Caption %>" /></a> <br /><br /><%= image.Caption %><br /><br /><br /> <% } %> Any help would be greatly appreciated!! Let me know of any questions you have as well. :) Thanks!

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  • Silverlight: How can I built an overview display block for any XAML?

    - by Ryan Bates
    Hi all, I am trying to create a generic "overview" control for any XAML. A good example of the desired effect would be on Google Maps or Bing maps: The main map zooms into some content, while a small "overview" block is docked to one of the map corners, showing the user where he/she is zoomed into. My content is all placed inside a <Canvas>, which can then be scaled and zoomed with transforms. While the user does this kind of navigation, I would like to give them a visual indication of where they are in the larger context of the content. I have tried to take a 'screenshot' of the XAML before the user starts navigating, i.e. create a WriteableBitmap wbImageData = new WriteableBitmap(TheCanvas, null); and then displaying it in an Image. Based on the user's scrolling and zooming activity, a Rectangle displays which part of the content is currently visible in the display area. This works OK-ish (still clunky), but the image has to be redone everytime the content changes. Is there a simple way to create this kind of preview, or does anyone know of a component that does it? Thanks!

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  • In Google Chrome, how do I bring an existing popup window to the front using javascript from the par

    - by brahn
    I would like to have a button on a web page with the following behavior: On the first click, open a pop-up. On later clicks, if the pop-up is still open, just bring it to the front. If not, re-open. The below code works in Firefox (Mac & Windows), Safari (Mac & Windows), and IE8. (I have not yet tested IE6 or IE7.) However, in Google Chrome (both Mac & Windows) later clicks fail to bring the existing pop-up to the front as desired. How can I make this work in Chrome? <head> <script type="text/javascript"> var popupWindow = null; var doPopup = function () { if (popupWindow && !popupWindow.closed) { popupWindow.focus(); } else { popupWindow = window.open("http://google.com", "_blank", "width=200,height=200"); } }; </script> </head> <body> <button onclick="doPopup(); return false"> create a pop-up </button> </body> Background: I am re-asking this question specifically for Google Chrome, as I think I my code solves the problem at least for other modern browsers and IE8. If there is a preferred etiquette for doing so, please let me know.

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  • How to filter Many2Many / Generic Relations properly with Q?

    - by HWM-Rocker
    Hi, I have 3 Models, the TaggedObject has a GenericRelation with the ObjectTagBridge. And the ObjectTagBridge has a ForeignKey to the Tag Model. class TaggedObject(models.Model): """ class that represent a tagged object """ tags = generic.GenericRelation('ObjectTagBridge', blank=True, null=True) class ObjectTagBridge(models.Model): """ Help to connect a generic object to a Tag. """ # pylint: disable-msg=W0232,R0903 content_type = models.ForeignKey(ContentType) object_id = models.PositiveIntegerField() content_object = generic.GenericForeignKey('content_type', 'object_id') tag = models.ForeignKey('Tag') class Tag(models.Model): ... when I am attaching a Tag to an Object, I am creating a new ObjectTagBridge and set its ForeignKey tag to the Tag I want to attach. That is working fine, and I can get all Tags that I attached to my Object very easy. But when I want to get (filter) all Objects that have Tag1 and Tag2 I tried to something like this: query = Q(tags__tag=Tag1) & Q(tags__tag=Tag2) object_list = TaggedObjects.filter(query) but now my object_list is empty, because it is looking for TaggedObjects that have one ObjectTagBridge with 2 tag objects, the first with Tag1 and the second with Tag2. I my application will be more complex Q queries than this one, so I think I need a solution with this Q object. In fact any combination of binary conjunctions, like: (...) and ( (...) or not(...)) How can I filter this correctly? Every answer is welcome, maybe there is also a different way do achieve this. thx for your help!!!

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  • computes the number of possible orderings of n objects under the relations < and =

    - by hilal
    Here is the problem : Give a algorithm that takes a positive integer n as input, and computes the number of possible orderings of n objects under the relations < and =. For example, if n = 3 the 13 possible orderings are as follows: a = b = c, a = b < c, a < b = c, a < b < c, a < c < b, a = c < b, b < a = c, b < a < c, b < c < a, b = c < a, c < a = b, c < a < b, c < b < a. Your algorithm should run in time polynomial in n. I'm null to this problem. Can you find any solution to this dynamic-programming problem?

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  • error while reading Excel sheet

    - by Lalit
    Hi, I have code to read Excel from c3 language : DataTable dtChildrenData = new DataTable(); OdbcConnection oConn = null; try { if (File.Exists(strSheetPath)) { oConn = new OdbcConnection(); oConn.ConnectionString = @"DSN=Excel Files;DBQ=" + strSheetPath + @";DriverId=1046;FIL=excel 12.0;MaxBufferSize=2048;PageTimeout=5;"; OdbcCommand oComm = new OdbcCommand(); oComm.Connection = oConn; oComm.CommandText = "Select * From [Sheet1$]"; DataSet ds = new DataSet(); OdbcDataAdapter oAdapter = new OdbcDataAdapter(oComm); oConn.Open(); oAdapter.Fill(ds); dtChildrenData = ds.Tables[0]; } } finally { oConn.Close(); } return dtChildrenData; But getting this error when i deploy the web application on IIS. Wherere as it is running fine locally. ERROR [IM002] [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified How to solve this. Please let me know if any information required to answer this question (about configuration)

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  • NHibernate query against the key field of a dictionary (map)

    - by Carl Raymond
    I have an object model where a Calendar object has an IDictionary<MembershipUser, Perms> called UserPermissions, where MembershipUser is an object, and Perms is a simple enumeration. This is in the mapping file for Calendar as <map name="UserPermissions" table="CalendarUserPermissions" lazy="true" cascade="all"> <key column="CalendarID"/> <index-many-to-many class="MembershipUser" column="UserGUID" /> <element column="Permissions" type="CalendarPermission" not-null="true" /> </map> Now I want to execute a query to find all calendars for which a given user has some permission defined. The permission is irrelevant; I just want a list of the calendars where a given user is present as a key in the UserPermissions dictionary. I have the username property, not a MembershipUser object. How do I build that using QBC (or HQL)? Here's what I've tried: ISession session = SessionManager.CurrentSession; ICriteria calCrit = session.CreateCriteria<Calendar>(); ICriteria userCrit = calCrit.CreateCriteria("UserPermissions.indices"); userCrit.Add(Expression.Eq("Username", username)); return calCrit.List<Calendar>(); This constructed invalid SQL -- the WHERE clause contained WHERE membership1_.Username = @p0 as expected, but the FROM clause didn't include the MemberhipUsers table. Also, I really had to struggle to learn about the .indices notation. I found it by digging through the NHibernate source code, and saw that there's also .elements and some other dotted notations. Where's a reference to the allowed syntax of an association path? I feel like what's above is very close, and just missing something simple.

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  • Intent provided by Cursor is not fired correctly (LiveFolders)

    - by Felix
    In my desperation with trying to get LiveFolders working, I have tried the following in my LiveFolder ContentProvider: public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { MatrixCursor mc = new MatrixCursor(new String[] { LiveFolders._ID, LiveFolders.NAME, LiveFolders.INTENT } ); Intent i = null; for (int j=0; j < 5; j++) { i = new Intent(Intent.ACTION_VIEW, Uri.parse("http://www.google.com/")); mc.addRow(new Object[] { j, "hello", i} ); } return mc; } Which, in all normalness, should launch the Browser and display the Google homepage when clicking on an item in the LiveFolder. But it doesn't. It gives a Application is not installed on your phone error. No, I'm not defining a base intent for my LiveFolder. logcat says: I/ActivityManager( 74): Starting activity: Intent { act=android.intent.action.VIEW dat=Intent { act=android.intent.action.VIEW dat=http://www.google.com/ } flg=0x10000000 } It seems it embeds the Intent I give it in the data section of the actually fired Intent. Why is it doing this? I'm really starting to believe it's a platform bug.

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  • I have a fucntion that create histogram of each Bitmap. How can i create another 3 histograms for R.G.B of each Bitmap?

    - by Daniel Lip
    This is the histogram function im using today and if im not worng it's creating an histogram by Gray color. What i want is another fucntion that will return me 3 histograms of each Bitmap: The first histogram will be of the Red color of the bitmap the second for the Green color and the last one for the Blue color. public static long[] GetHistogram(Bitmap b) { long[] myHistogram = new long[256]; BitmapData bmData = null; try { //Lock it fixed with 32bpp bmData = b.LockBits(new Rectangle(0, 0, b.Width, b.Height), ImageLockMode.ReadOnly, PixelFormat.Format32bppArgb); int scanline = bmData.Stride; System.IntPtr Scan0 = bmData.Scan0; unsafe { byte* p = (byte*)(void*)Scan0; int nWidth = b.Width; int nHeight = b.Height; for (int y = 0; y < nHeight; y++) { for (int x = 0; x < nWidth; x++) { long Temp = 0; Temp += p[0]; // p[0] - blue, p[1] - green , p[2]-red Temp += p[1]; Temp += p[2]; Temp = (int)Temp / 3; myHistogram[Temp]++; //we do not need to use any offset, we always can increment by pixelsize when //locking in 32bppArgb - mode p += 4; } } } b.UnlockBits(bmData); } catch { try { b.UnlockBits(bmData); } catch { } } return myHistogram; } How may i do it ?

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  • How To Deal With Exceptions In Large Code Bases

    - by peter
    Hi All, I have a large C# code base. It seems quite buggy at times, and I was wondering if there is a quick way to improve finding and diagnosing issues that are occuring on client PCs. The most pressing issue is that exceptions occur in the software, are caught, and even reported through to me. The problem is that by the time they are caught the original cause of the exception is lost. I.e. If an exception was caught in a specific method, but that method calls 20 other methods, and those methods each call 20 other methods. You get the picture, a null reference exception is impossible to figure out, especially if it occured on a client machine. I have currently found some places where I think errors are more likely to occur and wrapped these directly in their own try catch blocks. Is that the only solution? I could be here a long time. I don't care that the exception will bring down the current process (it is just a thread anyway - not the main application), but I care that the exceptions come back and don't help with troubleshooting. Any ideas? I am well aware that I am probably asking a question which sounds silly, and may not have a straightforward answer. All the same some discussion would be good.

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  • Hibernate collection mapping Problem

    - by Geln Yang
    Hi, There is a table Item like, code,name 01,parent1 02,parent2 0101,child11 0102,child12 0201,child21 0202,child22 Create a java object and hbm xml to map the table.The Item.parent is a Item whose code is equal to the first two characters of its code : class Item{ String code; String name; Item parent; List<Item> children; .... setter/getter.... } <hibernate-mapping> <class name="Item" table="Item"> <id name="code" length="4" type="string"> <generator class="assigned" /> </id> <property name="name" column="name" length="50" not-null="true" /> <many-to-one name="parent" class="Item" not-found="ignore"> <formula> <![CDATA[ (select i.code,r.name from Item i where (case length(code) when 4 then i.code=SUBSTRING(code,1,2) else false end)) ]]> </formula> </many-to-one> <bag name="children"></bag> </class> </hibernate-mapping> I try to use formula to define the many-to-one relationship,but it doesn't work!Is there something wrong?Or is there other method? Thanks! ps,I use mysql database.

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  • how to send image to remote server using web services in android

    - by Aswan
    get image from sdcard and store that image to remote server. i am getting the image from sdcard and i converterd that image to bytearray by using bitmap .but what's the problem if i oberver byte array it is showing some different values it is not matching with .net image byte array conversion. can u pl help if you have any solution it is very urgent to me following is the code i am using can u pl suggest me FileInputStream fin = new FileInputStream(new File("/sdcard/pictures/1.jpg")); BufferedInputStream bis = new BufferedInputStream(fin,3000); byte[] data = new byte[bis.available()]; bis.read(data, 0, data.length); byte[] data1=new byte[data.length]; for (int i = 0; i < data.length; i++) { System.out.print(data[i]); data1[i]=data[i]; } System.out.println("5..................."+data1); Bitmap bitmap = BitmapFactory.decodeByteArray(data1,0,data1.length); System.out.println("6..................."+data1.length); Log.v("hgfjohfjghjdfhgj",""+bitmap); if(bitmap!=null) image.setImageBitmap(bitmap); else Log.e("Bitmap "," Not Created");

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  • Browser freezes when try to call a JS function along with submission of a form.

    - by Waseem
    I have form in my view like following 1 <div> 2 <% form_tag facebook_user_path do %> 3 <label>Use my photo and name from facebook?</label><br /> 4 <%= check_box_tag 'use_name_and_photo', 'yes', true %> 5 <img src="<%= @user.pic %>" /><% @user.name %> 6 7 <%= submit_tag "Finish", :id => "use_name_and_photo_submit" %> 8 <% end %> 9 </div> I have attached some JS handlers using Jquery to this form. 1 var fb = { 2 extendedPermissions: function () { 3 $("#use_name_and_photo_submit").click(function (event) { 4 FB.Connect.showPermissionDialog("email,read_stream,publish_stream", function (perms) { 5 if (!perms) { 6 alert("You have to grant facebook extended permissions to further browse the application."); 7 } else { 8 $("form").submit(function () { 9 $.post($(this).attr("action"), $(this).serialize(), null, "script"); 10 }); 11 } 12 }); 13 event.preventDefault(); 14 return false; 15 }); 16 } 17 }; 18 19 $(document).ready(function () { 20 fb.extendedPermissions(); 21 }); What I want is that when the user clicks on the "Finish" button, he is prompted for the facebook permissions dialogue and when he gives the permissions, the form is submitted to FacebookUsersController. Right now when I click the "Finish" button, facebook permissions dialogue is initiated but before I am prompted for the actual permission submission window, the browser freezes. Just like I have pressed Esc during the process. In fact status bar of the browser says "Stopped". Any help is highly appreciated.

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  • Filp route value in asp.net mvc routes

    - by Herman
    Hi all, I am new to asp.net mvc, so please bear with me. We have the following route dictionary setup. routes.MapRoute( "Default", // Route name "{language}/{controller}/{action}/{id}", // URL with parameters new { language = "en", controller = "Home", action = "Index", id = "" } // Parameter defaults ); for any given page in our app, we to render a link to the a french version of the same page. For example, the page: http://www.example.com/en/home should have link on that page that points to http://www.example.com/fr/home Now I have the following UrlHelper extension method public static string FilpLanguage(this UrlHelper urlHelper) { var data = urlHelper.RequestContext.RouteData; if (System.Threading.Thread.CurrentThread.CurrentCulture == CultureInfo.GetCultureInfoByIetfLanguageTag("en-CA")) data.Values["language"] = "fr"; else data.Values["language"] = "en"; return urlHelper.RouteUrl(data.Values.Where(item => item.Value != null)); } However, calling FilpLanguage on www.example.com/en/home will return the following URL: www.example.com/en/home?current=[,] Am I missing something here? where did the current parameter come from? Thanks in advance.

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  • ASP.NET MVC 2.0 + Implementation of a IRouteHandler goes not fire

    - by Peter
    Can anybody please help me with this as I have no idea why public IHttpHandler GetHttpHandler(RequestContext requestContext) is not executing. In my Global.asax.cs I have public class MvcApplication : System.Web.HttpApplication { public static void RegisterRoutes(RouteCollection routes) { routes.IgnoreRoute("{resource}.axd/{*pathInfo}"); routes.MapRoute( "Default", // Route name "{controller}/{action}/{id}", // URL with parameters new { controller = "Home", action = "Index", id = "" } // Parameter defaults ); routes.Add("ImageRoutes", new Route("Images/{filename}", new CustomRouteHandler())); } protected void Application_Start() { RegisterRoutes(RouteTable.Routes); } } //CustomRouteHandler implementation is below public class CustomRouteHandler : IRouteHandler { public IHttpHandler GetHttpHandler(RequestContext requestContext) { // IF I SET A BREAK POINT HERE IT DOES NOT HIT FOR SOME REASON. string filename = requestContext.RouteData.Values["filename"] as string; if (string.IsNullOrEmpty(filename)) { // return a 404 HttpHandler here } else { requestContext.HttpContext.Response.Clear(); requestContext.HttpContext.Response.ContentType = GetContentType(requestContext.HttpContext.Request.Url.ToString()); // find physical path to image here. string filepath = requestContext.HttpContext.Server.MapPath("~/logo.jpg"); requestContext.HttpContext.Response.WriteFile(filepath); requestContext.HttpContext.Response.End(); } return null; } } Can any body tell me what I'm missing here. Simply public IHttpHandler GetHttpHandler(RequestContext requestContext) does not fire. I havn't change anything in the web.config either. What I'm missing here? Please help.

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  • Carbon, LSUIElement, and showing a window

    - by James Turner
    I have a Carbon LSUIElement application, which runs in the background (possibly with an icon in the menubar, depending on a pref) and occasionally needs to show a dialog to the user - sometimes in response to a user event, but sometimes in response to a background task failing or similar. (I'm using Qt 4.5, so the application is Carbon based; With Qt 4.6 things will be Cocoa based, but it sounds as if the problem may exist there too). The problem is that when I open a window, and show it, it doesn't get brought to the front. I assume this is an artefect of being an LSUIElement app. Qt uses SelectWindow in Carbon, and [makeKeyAndOrderFront] in Cocoa, to bring a window (and the app) to the front. To work around the problem, I tried going direct to the window server: (the first few steps are to get the WindowID, this will be simpler with Qt-Cocoa, since I can use NSWindow:nativeWindow) WindowRef ref = HIViewGetWindow((HIViewRef) aWidget->winId()); CGSWindow wid = GetNativeWindowFromWindowRef(ref); CGSConnection cid =_CGSDefaultConnection(); CGSOrderWindow(cid, wid, 1 /* above everything */, 0 /* NULL */); This works, sort of - the window comes to the front, but it's not highlighted or keyboard focused. Are there additional steps to fix those issues, or is there a simpler solution to the whole problem?

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  • Trying to write priority queue in Java but getting "Exception in thread "main" java.lang.ClassCastEx

    - by Dan
    For my data structure class, I am trying to write a program that simulates a car wash and I want to give fancy cars a higher priority than regular ones using a priority queue. The problem I am having has something to do with Java not being able to type cast "Object" as an "ArrayQueue" (a simple FIFO implementation). What am I doing wrong and how can I fix it? public class PriorityQueue<E> { private ArrayQueue<E>[] queues; private int highest=0; private int manyItems=0; public PriorityQueue(int h) { highest=h; queues = (ArrayQueue[]) new Object[highest+1]; <----problem is here } public void add(E item, int priority) { queues[priority].add(item); manyItems++; } public boolean isEmpty( ) { return (manyItems == 0); } public E remove() { E answer=null; int counter=0; do { if(!queues[highest-counter].isEmpty()) { answer = queues[highest-counter].remove(); counter=highest+1; } else counter++; }while(highest-counter>=0); return answer; } }

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  • How can I store large amount of data from a database to XML (memory problem)?

    - by Andrija
    First, I had a problem with getting the data from the Database, it took too much memory and failed. I've set -Xmx1500M and I'm using scrolling ResultSet so that was taken care of. Now I need to make an XML from the data, but I can't put it in one file. At the moment, I'm doing it like this: while(rs.next()){ i++; xmlStringBuilder.append("\n\t<row>"); xmlStringBuilder.append("\n\t\t<ID>" + Util.transformToHTML(rs.getInt("id")) + "</ID>"); xmlStringBuilder.append("\n\t\t<JED_ID>" + Util.transformToHTML(rs.getInt("jed_id")) + "</JED_ID>"); xmlStringBuilder.append("\n\t\t<IME_PJ>" + Util.transformToHTML(rs.getString("ime_pj")) + "</IME_PJ>"); //etc. xmlStringBuilder.append("\n\t</row>"); if (i%100000 == 0){ //stores the data to a file with the name i.xml storeKBR(xmlStringBuilder.toString(),i); xmlStringBuilder= null; xmlStringBuilder= new StringBuilder(); } and it works; I get 12 100 MB files. Now, what I'd like to do is to do is have all that data in one file (which I then compress) but if just remove the if part, I go out of memory. I thought about trying to write to a file, closing it, then opening, but that wouldn't get me much since I'd have to load the file to memory when I open it. P.S. If there's a better way to release the Builder, do let me know :)

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  • How do the operators < and > work with pointers?

    - by Øystein
    Just for fun, I had a std::list of const char*, each element pointing to a null-terminated text string, and ran a std::list::sort() on it. As it happens, it sort of (no pun intended) did not sort the strings. Considering that it was working on pointers, that makes sense. According to the documentation of std::list::sort(), it (by default) uses the operator < between the elements to compare. Forgetting about the list for a moment, my actual question is: How do these (, <, =, <=) operators work on pointers in C++ and C? Do they simply compare the actual memory addresses? char* p1 = (char*) 0xDAB0BC47; char* p2 = (char*) 0xBABEC475; e.g. on a 32-bit, little-endian system, p1 p2 because 0xDAB0BC47 0xBABEC475? Testing seems to confirm this, but I thought it'd be good to put it on StackOverflow for future reference. C and C++ both do some weird things to pointers, so you never really know...

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  • What should the name of this class be?

    - by Tim Murphy
    Naming classes is sometimes hard. What do you think name of the class should be? I originally created the class to use as a cache but can see its may have other uses. Example code to use the class. Dim cache = New NamePendingDictionary(Of String, Sample) Dim value = cache("a", Function() New Sample()) And here is the class that needs a name. ''' <summary> ''' Enhancement of <see cref="System.Collections.Generic.Dictionary"/>. See the Item property ''' for more details. ''' </summary> ''' <typeparam name="TKey">The type of the keys in the dictionary.</typeparam> ''' <typeparam name="TValue">The type of the values in the dictionary.</typeparam> Public Class NamePendingDictionary(Of TKey, TValue) Inherits Dictionary(Of TKey, TValue) Delegate Function DefaultValue() As TValue ''' <summary> ''' Gets or sets the value associated with the specified key. If the specified key does not exist ''' then <paramref name="createDefaultValue"/> is invoked and added to the dictionary. The created ''' value is then returned. ''' </summary> ''' <param name="key">The key of the value to get.</param> ''' <param name="createDefaultValue"> ''' The delegate to invoke if <paramref name="key"/> does not exist in the dictionary. ''' </param> ''' <exception cref="T:System.ArgumentNullException"><paramref name="key" /> is null.</exception> Default Public Overloads ReadOnly Property Item(ByVal key As TKey, ByVal createDefaultValue As DefaultValue) As TValue Get Dim value As TValue If createDefaultValue Is Nothing Then Throw New ArgumentNullException("createValue") End If If Not Me.TryGetValue(key, value) Then value = createDefaultValue.Invoke() Me.Add(key, value) End If Return value End Get End Property End Class

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  • MVC3 View For Loop values initialization

    - by Ryan
    So I have a for loop in my View that is supposed to render out the input boxes. Now inside these input boxes I want to put lables that disappear when you click on them. This is all simple. Now it's probably because my brain was wired for php first, and it has been difficult to get it to think in lambdas and object orientation, but I can't figure out how to do this: @{ for (int i = 0; i < 3; i++) { <div class="editor-label grid_2">User</div> Model.Users[i].UserFirstName = "First Name"; Model.Users[i].UserLastName = "Last Name"; Model.Users[i].UserEmailAddress = "Email Address"; <div class="grid_10"> @Html.TextBoxFor(m => Model.Users[i].UserFirstName, new { @class = "user-input" }) @Html.TextBoxFor(m => Model.Users[i].UserLastName, new { @class = "user-input" }) @Html.TextBoxFor(m => Model.Users[i].UserEmailAddress, new { @class = "user-input-long" }) @Html.CheckBoxFor(m => Model.Users[i].IsUserAdmin) <span>&nbsp;admin?</span> </div> <div class="clear"> </div> } } And initialize the values for the users. And you're probably thinking "Of course that won't work. You're going to get a Null Reference Exception", and you would be correct. I might need to initialize them somewhere else and I don't realize it but I'm just not sure. I've tried the [DefaultValue("First Name")] route and that doesn't work. I'm probably thinking about this wrong, but my brain is already shot from trying to figure out how to wire up these events to the controller, so any help would be appreciated!

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