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  • Error in Android's clearCheck() for RadioGroup?

    - by Manuel R. Ciosici
    I'm having an issue with RadioGroup's clearChecked(). I'm displaying a multiple choice question to the user and after the user selects an answer I check the answer, give him some feedback and then move to the next question. In the process of moving to the next question I clearCheck on the RadioGroup. Can anyone explain to me why the onCheckedChanged method is called 3 times? Once when the change actually occurs (with the user changes), once when I clearCheck(with -1 as the selected id) and once in between (with the user changes again)? As far as I could tell the second trigger is provoked by clearCheck. Code below: private void checkAnswer(RadioGroup group, int checkedId){ // this makes sure it doesn't blow up when the check is cleared // also we don't check the answer when there is no answer if (checkedId == -1) return; if (group.getCheckedRadioButtonId() == -1) return; // check if correct answer if (checkedId == validAnswerId){ score++; this.giveFeedBack(feedBackType.GOOD); } else { this.giveFeedBack(feedBackType.BAD); } // allow for user to see feedback and move to next question h.postDelayed(this, 800); } private void changeToQuestion(int questionNumber){ if (questionNumber >= this.questionSet.size()){ // means we are past the question set // we're going to the score activity this.goToScoreActivity(); return; } //clearing the check gr.clearCheck(); // give change the feedback back to question imgFeedback.setImageResource(R.drawable.question_mark); //OTHER CODE HERE } and the run method looks like this public void run() { questionNumber++; changeToQuestion(questionNumber); }

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  • In Safari, using jQuery a Form Input Text Field does not receive focus after alert is displayed. Why

    - by Rob
    I have an ASPX web form. I use jQuery to simply my Javascript. I use a Javascript validation script to validate each of the form fields' values. If an error occurs, I popup an alert with an error message. Then I transfer focus to the underlying element. Here are examples I have tried. Using jQuery: var Form_FieldDef = function(name) { this.name = name; this.SetFocus = function() { $('#' + this.name)[0].focus(); } this.Validate = function() { var isvalid = true; if ( $.trim($('#' + this.name).val()) == '') { alert("Your entry is empty"); this.SetFocus(); isvalid = false; } return isvalid; } } This works on IE7, IE8, Opera, Chrome, and Firefox. It does not work on Safari 4 on PC. I don't have a Mac. So I changed the SetFocus method to this. this.SetFocus = function() { var fld = document.getElementById(this.name); if (fld != null) fld.focus(); } This works on IE7, IE8, Opera, Chrome, and Firefox. It does not work on Safari 4 on PC. I stepped through the code with VS 2008 debugger, and I'm calling the focus method on the underlying element.

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  • Setting Image.Source doesn't update when loading from a resource.

    - by ChrisF
    I've got this definition in my XAML: <Image Name="AlbumArt" Source="/AlbumChooser2;component/Resources/help.png" /> The image is display OK on startup. In my code I'm looking for mp3's to play and I display the associated album art in this Image. Now if there's no associated image I want to display a "no image" image. So I've got one defined and I load it using: BitmapImage noImage = new BitmapImage( new Uri("/AlbumChooser2;component/Resources/no_image.png", UriKind.Relative)); I've got a helper class that finds the image if there is one (returning it as a BitmapImage), or returns null if there isn't one: if (findImage.Image != null) { this.AlbumArt.Source = findImage.Image; // This works } else { this.AlbumArt.Source = noImage; // This doesn't work } In the case where an image is found the source is updated and the album art gets displayed. In the case where an image isn't found I don't get anything displayed - just a blank. I don't think that it's the setting of AlbumArt.Source that's wrong, but the loading of the BitmapImage. If I use a different image it works, but if I recreate the image it doesn't work. What could be wrong with the image?

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  • C++: inheritance problem

    - by Helltone
    It's quite hard to explain what I'm trying to do, I'll try: Imagine a base class A which contains some variables, and a set of classes deriving from A which all implement some method bool test() that operates on the variables inherited from A. class A { protected: int somevar; // ... }; class B : public A { public: bool test() { return (somevar == 42); } }; class C : public A { public: bool test() { return (somevar > 23); } }; // ... more classes deriving from A Now I have an instance of class A and I have set the value of somevar. int main(int, char* []) { A a; a.somevar = 42; Now, I need some kind of container that allows me to iterate over the elements i of this container, calling i::test() in the context of a... that is: std::vector<...> vec; // push B and C into vec, this is pseudo-code vec.push_back(&B); vec.push_back(&C); bool ret = true; for(i = vec.begin(); i != vec.end(); ++i) { // call B::test(), C::test(), setting *this to a ret &= ( a .* (&(*i)::test) )(); } return ret; } How can I do this? I've tried two methods: forcing a cast from B::* to A::*, adapting a pointer to call a method of a type on an object of a different type (works, but seems to be bad); using std::bind + the solution above, ugly hack; changing the signature of bool test() so that it takes an argument of type const A& instead of inheriting from A, I don't really like this solution because somevar must be public.

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  • Why my jquery function is not firing on Firefox

    - by Cristian Boariu
    I have some trouble with some jquery method (for some checkboxes I want them to fire on checked/unchecked so I can do something then). This method works perfectly on Chrome and IE but not on latest FF. jQuery(function () { jQuery(':checkbox').change(function () { var counter = jQuery('.count').text(); var thisCheck = jQuery(this); if (thisCheck.is(':checked')) { counter++; //apply green color to the selected row jQuery(this).closest('tr').addClass('checked'); } else { counter--; //remove green color to the selected row jQuery(this).closest('tr').removeClass('checked'); } jQuery('.count').html(counter); //enable export button when there are selected emails to be exported if (counter > 0) { jQuery(".exportButton").removeAttr("disabled", ""); } else { jQuery(".exportButton").attr("disabled", "disabled"); } }); }); Basically it's simply not firing...Even with Debug is not catching the first line (function declare nor other lines too). If I move this javascript(without function declare) inside jQuery(document).ready(function ($) { all works nice on Firefox too... Yes, I do use jQuery.noConflict(); before jQuery(document).ready(function ($) { Do you know why this happens?

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  • Jquery tooltip absolute position above a link which is inside paragraph text?

    - by BerggreenDK
    I am trying to retrieve the position of an HTML element inside a paragraph. Eg. a span or anchor. I would also like the width of the element. So that when I hover the object, I can activate/build/show a sort of toolbar/tooltip above the element dynamically. I need it to be dynamically added to exisiting content, so somekinda "search-replace" jQuery thingy that scans the elements within eg. a DIV and then does this for all that matches this "feature". Main problem/question is: How do I retrieve the "current absolute" position of the element I am hovering with the mouse. I dont want the toolbar/tooltip to be following the mouse, but instead it must "snap" to the element its hovering. so I was thinking: "place BOX -20px from current element. Match width.... Possible? is there a jQuery plugin for this already - or? Sample code: <div class="helper"> <h1>headline</h1> <p>Here is some sample text. But <a href="somewhere.htm" class="help help45">this is with an explanation you can hover</a>. <a href="somewhereelse.htm">And this isnt.</a> <ul> <li>We could also do it <a href="somewhere.htm" class="help help32">inside a bullet list</a></li> </ul> </div> The .help is the class triggering the "help" and the .help45 or .help32 is the helpsection needed to be shown (but thats another task later, as I am hoping to retreive the "id" from the "help45" so a serverlookup for id=45 can load the text needed to be shown. Nb. if the page scrolls etc. the helptip still needs to follow the item on the page until closed/hidden.

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  • WCF operationcontract with List type unavailable in (Silverlight) client

    - by Dave
    This is the first time I have tried returning a List of data to a Silverlight client, so I'm having trouble getting the client to recognize this operationcontract. All others are fine. I have a method on the server called ReadOwFileData that needs to return a List. ReadOwFileDataCompletedEventArgs shows up in the Object Browser in the client, but not ReadOwFileDataAsync. What I want is similar to the tutorial here. The Dictionary collection type on the client is set to System.Collections.Generic.List. I tried deleting and recreating the service reference. Web.Config on the server is using basicHttpBinding. Here is the operationcontract on the server: [OperationContract] public List<OwFileData> ReadOwFileData(string OrderID) { DataClasses1DataContext db = new DataClasses1DataContext(); var dFileData = (from p in db.OwFileDatas where p.OrderID == OrderID select p).ToList(); List<OwFileData> x = new List<OwFileData>(dFileData); return x; } Incidently, this works fine: [OperationContract] public Customer GetShippingAndContactInfo(string login, string ordernum) { DataClasses1DataContext db = new DataClasses1DataContext(); Customer dInfo = (from p in db.Customers where p.Login == login select p).Single(); return dInfo; } I would like to read this data in the client and place it into an object I created called ObservableCollection. But that obviously can't happen until the client can see the method on the server. I do not know if this is an acceptable start, but this is what is on the client so far. The ReadOwFileDataAsync object is null: void populatefilesReceivedDataSource(string OrderID) { ArtUpload.ServiceReference1.UploadServiceClient client = new ArtUpload.ServiceReference1.UploadServiceClient(); var myList = client.ReadOwFileDataAsync(OrderID); // can I just itterate thru the list instead of 'binding' }

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  • ActionListener isn't Implementing

    - by Nick Gibson
    JFrameWithPanel is not abstract and does not override abstract method actionPerformed(java.awt.event.ActionEvent) in java.awt.event.ActionListener public class JFrameWithPanel extends JFrame implements ActionListener I Don't get this code. Book and Java site tells me this is the syntax for the method, but again this error shows up constantly. import javax.swing.*; import javax.swing.JOptionPane; import java.awt.*; import java.awt.event.*; import java.lang.Math.*; import java.lang.Integer.*; import java.util.*; import java.util.Random; import java.io.*; import java.text.*; import java.text.DecimalFormat.*; public class JFrameWithPanel extends JFrame implements ActionListener { JButton button = new JButton("Exit"); public JFrameWithPanel() { super("JFrame with Panel"); JComboBox packageChoice = new JComboBox(); packageChoice.addItem("A+ Certification"); packageChoice.addItem("Network+ Certification "); packageChoice.addItem("Security+ Certifictation"); packageChoice.addItem("CIT Full Test Package"); packageChoice.addActionListener(this); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); JPanel pane = new JPanel(); pane.add(button); pane.add(packageChoice); setContentPane(pane); setSize(200,100); setVisible(true); } } then later public class CreateJFrameWithPanel { public static void main(String[] args) { JFrameWithPanel panel = new JFrameWithPanel(); } }

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  • Validating a phone number in Android PreferenceScreen

    - by djechelon
    I have a PreferenceScreen in which the user is capable, if system can't autodetect it, to enter the device's phone number. I'm still learning this part of Android but I managed to understand a bit of PreferenceScreens by examples provided by Android SDK itself and a few tutorials. What I want is that the user can save the phone number only if null or valid, where by "valid" I mean running a generic validation logic (ie. an anonymous method that returns true or false, that can be reused in any possible situation*) or better, just to simplify things, ^(\+39)?3[0-9]{9}$ For now I have the following XML snip <EditTextPreference android:inputType="phone" android:key="@string/preference_phoneNo" android:selectAllOnFocus="true" android:singleLine="true" android:summary="@string/pref_phoneNumber_description" android:title="@string/pref_phoneNumber" /> and following code by courtesy of Eclipse New Activity wizard: private void setupSimplePreferencesScreen() { if (!isSimplePreferences(this)) { return; } addPreferencesFromResource(R.xml.pref_general); bindPreferenceSummaryToValue(findPreference(getString(R.string.preference_phoneNo))); } addPreferenceFromResource is supposed to load the XML node and add the preference to the screen, while binPreferenceSummaryToValue is supposed to make description text change when preference is updated. Just for sake of completeness for those who don't like code courtesy of the IDE, the second method is provided by Eclipse who also provides a private class in the code file that is /** * A preference value change listener that updates the preference's summary * to reflect its new value. */ In the general case, what should I do to perform validation logic before the preference gets saved when I click OK on the preference editor? Where is the validation logic to be put in a PreferenceScreen? *Aren't we all here to learn?

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  • iPhone SDK: problem managing orientation with multiple view controllers.

    - by Tom
    I'm trying to build an iPhone application that has two subviews in the main window. Each view has its own UIViewController subclass associated with it. Also, within each controller's implementation, I've added the following method: -(BOOL)shouldAutorotateToInterfaceOrientation: (UIInterfaceOrientation)interfaceOrientation { return YES; } Thus, I would expect both of the views to respond to changes in orientation. However, this is not the case. Only the first view added to the app's main window responds to orientation. (If I swap the order the views are added, then only the other view responds. In other words, either will work--but only one at a time.) Why is this? Is it not possible to handle the orientation changes of more than one view? Thanks! EDIT: Someone else had this question, so I'm copying my solution here: I was able to address this issue by providing a root view and a root view controller with the method "shouldAutoRotate..." and adding my other views as subviews to the root view. The subviews inherit the auto-rotating behavior, and their associated view controllers shouldn't need to override "shouldAutoRotate..."

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  • Rapid Opening and Closing System.IO.StreamWriter in C#

    - by ccomet
    Suppose you have a file that you are programmatically logging information into with regards to a process. Kinda like your typical debug Console.WriteLine, but due to the nature of the code you're testing, you don't have a console to write onto so you have to write it somewhere like a file. My current program uses System.IO.StreamWriter for this task. My question is about the approach to using the StreamWriter. Is it better to open just one StreamWriter instance, do all of the writes, and close it when the entire process is done? Or is it a better idea to open a new StreamWriter instance to write a line into the file, then immediately close it, and do this for every time something needs to be written in? In the latter approach, this would probably be facilitated by a method that would do just that for a given message, rather than bloating the main process code with excessive amounts of lines. But having a method to aid in that implementation doesn't necessarily make it the better choice. Are there significant advantages to picking one approach or the other? Or are they functionally equivalent, leaving the choice on the shoulders of the programmer?

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  • Variable won't store in session

    - by Mittens
    So I'm trying to store the "rank" of a user when they log in to a control panel which displays different options depending on the given rank. I used the same method as I did for storing and displaying the username, which is displayed on the top of each page and works just fine. I can't for the life of me figure out why it won't work for the rank value, but I do know that it is not saving it in the session. Here is the bit that's not working; $username = ($_POST['username']); $password = hash('sha512', $_POST['password']); $dbhost = 'mysql:host=¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦;dbname=¦¦¦¦¦¦¦¦¦¦¦'; $dbuser = '¦¦¦¦¦¦¦¦¦¦¦'; $dbpassword = '¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦¦'; try { $db = new PDO($dbhost, $dbuser, $dbpassword); $statement = $db->prepare("select password from users where email = :name"); $statement->execute(array(':name' => $username)); $result = $statement->fetch(); $pass = $result[password]; $rank = $result[rank];} catch(PDOException $e) {echo $e->getMessage();} if ($password == $pass) { session_start(); $_SESSION['username'] = $username; $_SESSION['rank'] = $rank; header('Location: http://¦¦¦¦¦¦¦¦¦.ca/manage.php'); } else{ include'../../includes/head.inc'; echo '<h1>Incorrect username or password.</h1>'; include'../../includes/footer.inc'; } I'm also new to the whole PDO thing, hence why my method of authenticating the password is pretty sketchy.

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  • Changing pointer of self

    - by rob5408
    I have an object that I alloc/init like normal just to get a instance. Later in my application I want to load state from disk for that object. I figure I could unarchive my class (which conforms to NSCoding) and just swap where my instance points to. To this end I use this code... NSString* pathForDataFile = [self pathForDataFile]; if([[NSFileManager defaultManager] fileExistsAtPath:pathForDataFile] == YES) { NSLog(@"Save file exists"); NSData *data = [[NSMutableData alloc] initWithContentsOfFile:pathForDataFile]; NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:data]; [data release]; Person *tempPerson = [unarchiver decodeObjectForKey:@"Person"]; [unarchiver finishDecoding]; [unarchiver release]; if (tempPerson) { [self release]; self = [tempPerson retain]; } } Now when I sprinkled some NSLogs throughout my application I noticed self.person: <Person: 0x3d01a10> (After I create the object with alloc/init) self: <Person: 0x3d01a10> (At the start of this method) tempPerson: <Person: 0x3b1b880> (When I create the tempPerson) self: <Person: 0x3b1b880> (after i point self to the location of the tempPerson) self.person: <Person: 0x3d01a10> (After the method back in the main program) What am I missing?

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  • How to pass variables to slot methods in QT?

    - by Neko
    Hi. I'm making a little chat messenger program, which needs a list of chat channels the user has joined. To represent this list graphically, I have made a list of QPushButtons, which all represent a different channel. These buttons are made with the following method, and that's where my problem kicks in: void Messenger::addToActivePanels(std::string& channel) { activePanelsContents = this->findChild<QWidget *>(QString("activePanelsContents")); pushButton = new QPushButton(activePanelsContents); pushButton->setObjectName("pushButton"); pushButton->setGeometry(QRect(0, 0, 60, 60)); pushButton->setText(""); pushButton->setToolTip(QString(channel.c_str())); pushButton->setCheckable(true); pushButton->setChecked(false); connect(pushButton, SIGNAL(clicked()), this, SLOT(switchTab(channel))); } (activePanelContents is a QWidget that holds the list.) The point is that each button should call the switchTab(string& tabname) method when clicked, including the specific channel's name as variable. This implementation doesn't work though, and I haven't been able to find out how to properly do this, even after reading several pages on it on the internet. Can anybody please tell me how to do this? It'd be greatly appreciated, as always. :)

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  • Job queueing and execute Mechanism

    - by Calm Storm
    In my webservice all method calls submits jobs to a queue. Basically these operations take long time to execute, so all these operations submit a Job to a queue and return a status saying "Submitted". Then the client keeps polling using another service method to check for the status of the job. Presently, what I do is create my own Queue, Job classes that are Serializable and persist these jobs (i.e, their serialized byte stream format) into the database. So an UpdateLogistics operation just queues up a "UpdateLogisticsJob" to the queue and returns. I have written my own JobExecutor which wakes up every N seconds, scans the database table for any existing jobs, and executes them. Note the jobs have to persisted because these jobs have to survive app-server crashes. This was done a long time ago, and I used bespoke classes for my Queues, Jobs, Executors etc. But now, I would like to know has someone done something similar before? In particular, Are there frameworks available for this ? Something in Spring/Apache etc Any framework that is easy to adapt/debug and plays well along with libraries like Spring will be great.

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  • wx_ref and custom wx_object's

    - by Iogann
    Hi! I am developing MDI application with help of wxErlang. I have a parent frame, implemented as wx_object: -module(main_frame). -export([new/0, init/1, handle_call/3, handle_event/2, terminate/2]). -behaviour(wx_object). .... And I have a child frame, implemented as wx_object too: module(child_frame). -export([new/2, init/1, handle_call/3, handle_event/2, terminate/2]). -export([save/1]). -behaviour(wx_object). % some public API method save(Frame) -> wx_object:call(Frame, save). .... I want to call save/1 for an active child frame from the parent frame. There is my code: ActiveChild = wxMDIParentFrame:getActiveChild(Frame), case wx:is_null(ActiveChild) of false - child_frame:save(ActiveChild); _ - ignore end This code fails because ActiveChild is #wx_ref{} with state=[], but wx_object:call/2 needs #wx_ref{} where state is set to the pid of the process which we call. What is the right method to do this? I thought only to store a list of all created child frames with its pids in the parent frame and search the pid in this list, but this is ugly.

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  • C# : How to round-off hours based on Minutes(hours+0 if min<30, hours+1 otherwise) ?

    - by infant programmer
    I need to round-off the hours based on the minutes in a dateTime variable. The condition is : if minutes are less than 30, then minutes must be set to zero and no changes to hours, Else if minutes =30, then hours must be set to hours+1 and minutes are again set to zero. Seconds are ignored. example: 11/08/2008 04:30:49 should become 11/08/2008 05:00:00 and 11/08/2008 04:29:49 should become 11/08/2008 04:00:00 I have written a Code which works perfectly fine, but just wanted to know a better method if could be written and also would appreciate alternative method(s). string date1 = "11/08/2008 04:30:49"; DateTime startTime; DateTime.TryParseExact(date1, "MM/dd/yyyy HH:mm:ss", null, System.Globalization.DateTimeStyles.None, out startTime); if (Convert.ToInt32((startTime.Minute.ToString())) > 29) { startTime = DateTime.Parse(string.Format("{0}/{1}/{2} {3}:{4}:{5}", startTime.Month.ToString(), startTime.Day.ToString(), startTime.Year.ToString(), startTime.Hour.ToString(), "00", "00")); startTime = startTime.Add(TimeSpan.Parse("01:00:00")); Console.WriteLine("startTime is :: {0}", startTime.ToString("MM/dd/yyyy HH:mm:ss")); } else { startTime = DateTime.Parse(string.Format("{0}/{1}/{2} {3}:{4}:{5}", startTime.Month.ToString(), startTime.Day.ToString(), startTime.Year.ToString(), startTime.Hour.ToString(), "00", "00")); Console.WriteLine("startTime is :: {0}", startTime.ToString("MM/dd/yyyy HH:mm:ss")); }

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  • Why can't I pass a form field of type file to a CFFUNCTION using structure syntax?

    - by Eric Belair
    I'm trying to pass a form field of type "file" to a CFFUNCTION. The argument type is "any". Here is the syntax I am trying to use (pseudocode): <cfloop from="1" to="5" index="i"> <cfset fieldname = "attachment" & i /> <cfinvoke component="myComponent" method="attachFile"> <cfinvokeargument name="attachment" value="#FORM[fieldname]#" /> </cfinvoke> </cfloop> The loop is being done because there are five form fields named "attachment1", "attachment2", et al. This throws an exception in the function: coldfusion.tagext.io.FileTag$FormFileNotFoundException: The form field C:\ColdFusion8\...\neotmp25080.tmp did not contain a file. However, this syntax DOES work: <cfloop from="1" to="5" index="i"> <cfinvoke component="myComponent" method="attachFile"> <cfinvokeargument name="attachment" value="FORM.attachment#i#" /> </cfinvoke> </cfloop> I don't like writing code like that in the second example. It just seems like bad practice to me. So, can anyone tell me how to use structure syntax to properly pass a file type form field to a CFFUNCTION??

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  • C# Casting system.__comobject to class type

    - by ijrufus
    I have an Excel Add-In that I'm currently trying to set up a unit test framework for. For the unit tests I've followed this guide: http://blogs.msdn.com/b/varsha/archive/2010/08/17/writing-automated-test-cases-for-vsto-application.aspx It seems to work fine, until I want to return a class object from my interface. Specifying the class object as the return type throws a "return argument has an invalid type" exception when calling the method. Changing the return type from the class to an object allows me to call the method and get the object, but now I'm unable to cast it as the class and use it as intended, getting this exception message when I try: > Unable to cast COM object of type 'System.__ComObject' to class type > 'anaplan.Utility.XYCoordinates'. Instances of types that represent COM > components cannot be cast to types that do not represent COM > components; however they can be cast to interfaces as long as the > underlying COM component supports QueryInterface calls for the IID of > the interface. I've retrieved the Type name using VisualBasic.Information.TypeName and it's showing it as the class I expect. Is there any way to get the comobject cast back to the class? Or another way to access the properties it has? Or am I just being a bit stupid here?

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  • Interpreting item click in ListView

    - by Matt Huggins
    I'm working on my first Android project, and I created a menu via the XML method. My activity is pretty basic, in that it loads the main layout (containing a ListView with my String array of options). Here's the code inside my Activity: public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); // allow stuff to happen when a list item is clicked ListView ls = (ListView)findViewById(R.id.menu); ls.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { // @todo } }); } Within the onItemClick callback handler, I'd like to check which item was clicked, and load a new menu based upon that. Question 1: How do I go about figuring out which item was clicked? I can't find any straightforward examples on retrieving/testing the id value of the clicked item. Question 2: Once I have the id value, I assume I can just call the setContentView method again to change to another layout containing my new menu. Is that correct?

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  • Linear Interpolation. How to implement this algorithm in C ? (Python version is given)

    - by psihodelia
    There exists one very good linear interpolation method. It performs linear interpolation requiring at most one multiply per output sample. I found its description in a third edition of Understanding DSP by Lyons. This method involves a special hold buffer. Given a number of samples to be inserted between any two input samples, it produces output points using linear interpolation. Here, I have rewritten this algorithm using Python: temp1, temp2 = 0, 0 iL = 1.0 / L for i in x: hold = [i-temp1] * L temp1 = i for j in hold: temp2 += j y.append(temp2 *iL) where x contains input samples, L is a number of points to be inserted, y will contain output samples. My question is how to implement such algorithm in ANSI C in a most effective way, e.g. is it possible to avoid the second loop? NOTE: presented Python code is just to understand how this algorithm works. UPDATE: here is an example how it works in Python: x=[] y=[] hold=[] num_points=20 points_inbetween = 2 temp1,temp2=0,0 for i in range(num_points): x.append( sin(i*2.0*pi * 0.1) ) L = points_inbetween iL = 1.0/L for i in x: hold = [i-temp1] * L temp1 = i for j in hold: temp2 += j y.append(temp2 * iL) Let's say x=[.... 10, 20, 30 ....]. Then, if L=1, it will produce [... 10, 15, 20, 25, 30 ...]

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  • Accessing my own datalayer using RIA & Silverlight

    - by Norsten
    Is it possible for me to connect to my own data provide via WCF RIA services? I've created a small datalayer that connnects to DynamicAX datasource. I would like to use Silverlight 4 & RIA service to access that datalayer. At it's most basic -I've done the following... 1) I've added an empty domainclass to the webproject and in that class I created a simple method to return a string... [EnableClientAccess()] public class ProjectService : DomainService { public string TestViaRIA() { return "Hello!"; } } 2) I then added reference to the web project in my silvelight class and created a bit of code to try and invoke the method... using ProjectApp.Web; namespace ProjectApp.Views { public partial class ProjectControl : UserControl { public ProjectControl() { InitializeComponent(); ProjectContext ctx = new ProjectContext(); var x = ctx.TestViaRIA(); testTextBox.Text = x.ToString(); } } } the returned value is "{System.ServiceModel.DomainServices.Client.InvokeOperation}". I'm obviously doing something wrong here and I would appreciate some guidance on how I can achive this. Thanks in advance

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  • How to enforce that HTTP client uses conditional requests for updates?

    - by Day
    In a (proper RMM level 3) RESTful HTTP API, I want to enforce the fact that clients should make conditional requests when updating resources, in order to avoid the lost update problem. What would be an appropriate response to return to clients that incorrectly attempt unconditional PUT requests? I note that the (abandoned?) mod_atom returns a 405 Method Not Allowed with an Allow header set to GET, HEAD (view source) when an unconditional update is attempted. This seems slightly misleading - to me this implies that PUT is never a valid method to attempt on the resource. Perhaps the response just needs to have an entity body explaining that If-Match or If-Unmodified-Since must be used to make the PUT request conditional in which case it would be allowed? Or perhaps a 400 Bad Request with a suitable explanation in the entity body would be a better solution? But again, this doesn't feel quite right because it's using a 400 response for a violation of application specific semantics when RFC 2616 says (my emphasis): The request could not be understood by the server due to malformed syntax. But than again, I think that using 400 Bad Request for application specific semantics is becoming a widely accepted pragmatic solution (citation needed!), and I'm just being overly pedantic.

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  • Java Generics error when implementing Hibernate message interpolator

    - by Jayaprakash
    Framework: Spring, Hibernate. O/S: Windows I am trying to implement hibernate's Custom message interpolator following the direction of this Link. When implementing the below class, it gives an error "Cannot make a static reference to the non-static type Locale". public class ClientLocaleThreadLocal<Locale> { private static ThreadLocal tLocal = new ThreadLocal(); public static void set(Locale locale) { tLocal.set(locale); } public static Locale get() { return tLocal.get(); } public static void remove() { tLocal.remove(); } } As I do not know generics enough, not sure how is being used by TimeFilter class below and the purpose of definition in the above class. public class TimerFilter implements Filter { public void destroy() { } public void doFilter(ServletRequest req, ServletResponse res, FilterChain filterChain) throws IOException, ServletException { try { ClientLocaleThreadLocal.set(req.getLocale()); filterChain.doFilter(req, res); }finally { ClientLocaleThreadLocal.remove(); } } public void init(FilterConfig arg0) throws ServletException { } } Will doing the following be okay? Change static method/field in ClientLocaleThreadLocal to non-static method/fields In TimeFilter, set locale by instantiating new object as below. new ClientLocaleThreadLocal().set(req.getLocale()) Thanks for your help in advance

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  • How to make buttons in python/pygame?

    - by user1334014
    I'm making a game in pygame and on the first screen I want there to be buttons that you can press to (i) start the game, (ii) load a new screen with instructions, and (iii) exit the program. I've found this code online for button making, but I don't really understand it (I'm not that good at object oriented programming). If I could get some explanation as to what it's doing that would be great. Also, when I use it and try to open a file on my computer using the file path, I get the error sh: filepath :Permission denied, which I don't know how to solve. #load_image is used in most pygame programs for loading images def load_image(name, colorkey=None): fullname = os.path.join('data', name) try: image = pygame.image.load(fullname) except pygame.error, message: print 'Cannot load image:', fullname raise SystemExit, message image = image.convert() if colorkey is not None: if colorkey is -1: colorkey = image.get_at((0,0)) image.set_colorkey(colorkey, RLEACCEL) return image, image.get_rect() class Button(pygame.sprite.Sprite): """Class used to create a button, use setCords to set position of topleft corner. Method pressed() returns a boolean and should be called inside the input loop.""" def __init__(self): pygame.sprite.Sprite.__init__(self) self.image, self.rect = load_image('button.png', -1) def setCords(self,x,y): self.rect.topleft = x,y def pressed(self,mouse): if mouse[0] > self.rect.topleft[0]: if mouse[1] > self.rect.topleft[1]: if mouse[0] < self.rect.bottomright[0]: if mouse[1] < self.rect.bottomright[1]: return True else: return False else: return False else: return False else: return False def main(): button = Button() #Button class is created button.setCords(200,200) #Button is displayed at 200,200 while 1: for event in pygame.event.get(): if event.type == MOUSEBUTTONDOWN: mouse = pygame.mouse.get_pos() if button.pressed(mouse): #Button's pressed method is called print ('button hit') if __name__ == '__main__': main() Thank you to anyone who can help me.

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