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  • Multiple dropdown combination check and filter

    - by Tom
    Using Javascript / jQuery, I'm trying to build a "combination checker" that will take the values of three (but can be more) dropdown lists and filter the options based on a supplied list of allowed combinations. For example: DROPDOWNS Field 1: - value_1 - value_2 Field 2: - value_3 Field 3: - value_4 - value_5 COMBINATIONS - value_1, value_3, value_5 - value_1, value_3, value_4 - value_2, value_3, value_5 When a user selects Field 3 - value_4, the unavailable options will be disabled - ie, Field 1 - value_2 (there is no combination that allows value_2 and value_4 to be selected together). It would be really great if someone could provide some pointers on how this can be achieved or just provide a fresh perspective - I'm going round in circles on this one!

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  • How do you mentally handle going from writing managed to non-managed code?

    - by Glenn Sandoval
    ~80% of the code I write is in C#. The other ~20% is in C++. Whenever I have to switch from C# to C++, it takes me quite a while to mentally "shift gears" to thinking in C++. I make simple mistakes using pointers and memory allocation that I would not have made when I was in university. Is this normal? Does anyone else experience something similar and if so, what do you do to cut down on the time this wastes?

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  • "'Objects' may not respond to 'functions'" warnings.

    - by Andrew
    Hello all, for the last couple of weeks I've finally gotten into Obj-C from regular C and have started my first app. I've watched tutorials and read through a book along with a lot of webpages, but I know I've only just begun. Anyway, for most of the night and this morning, I've been trying to get this code to work, and now that it will compile, I have a few warnings. I've searched and found similar problems with solutions, but still no dice. What I'm trying to do is put an array made from a txt document into the popup list in a combo box. AwesomeBoxList.h: #import <Cocoa/Cocoa.h> @interface AwesomeBoxList : NSObject { IBOutlet NSComboBox *ComboBoz; } -(NSArray *) getStringzFromTxtz; - (void) awesomeBoxList; @end AwesomeBoxList.m: #import "AwesomeBoxList.h" @implementation AwesomeBoxList -(NSArray *)getStringzFromTxtz { ... return combind; } - (void) awesomeBoxList { [ComboBoz setUsesDataSource:YES]; [ComboBoz setDataSource: [ComboBoz getStringzFromTxtz]: //'NSComboBox' may not respond to 'getStringzFromTxtz' [ComboBoz comboBox:(NSComboBox *)ComboBoz objectValueForItemAtIndex: [ComboBoz numberOfItemsInComboBox:(NSComboBox *)ComboBoz]]]; /*'NSComboBox' may not respond to '-numberOfItemsInComboBox:' 'NSComboBox' may not respond to '-comboBox:objectValueForItemAtIndex:' 'NSComboBox' may not respond to '-setDataSource:' */ } @end So, with all of these errors and my still shallow knowledge of Obj-C, I must be making some sort of n00b mistake. Thanks for the help.

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  • How to get drag working properly in silverlight when mouse is not pressed ?

    - by Mrt
    Hello, I have the following code xaml <Canvas x:Name="LayoutRoot" > <Rectangle Canvas.Left="40" Canvas.Top="40" Width="20" Height="20" Name="rec" Fill="Red" MouseLeftButtonDown="rec_MouseLeftButtonDown" MouseMove="rec_MouseMove" /> </Canvas> code behind public partial class MainPage : UserControl { public MainPage() { InitializeComponent(); } public Point LastDragPosition { get; set; } private bool isDragging; private void rec_MouseMove(object sender, MouseEventArgs e) { if(!isDragging) { return; } var position = e.GetPosition(rec as UIElement); var newPosition = new Point( Canvas.GetLeft(rec) + position.X - LastDragPosition.X, Canvas.GetTop(rec) + position.Y - LastDragPosition.Y); Canvas.SetLeft(rec, newPosition.X); Canvas.SetTop(rec, newPosition.Y); LastDragPosition = e.GetPosition(rec as UIElement); } private void rec_MouseLeftButtonDown(object sender, MouseButtonEventArgs e) { isDragging = true; LastDragPosition = e.GetPosition(sender as UIElement); rec.CaptureMouse(); } } This issue is the rectangle follows the mouse if the mouse left button is down, but I would like the rectangle to move even when the mouse left button isn't down. It works, but if you move the mouse very slowly. If you move the mouse to quickly the rectangle stops moving (is the mouse capture lost ?) Cheers,

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  • weird access denied issue with WMI

    - by stackunderflow1
    I'm seeing a weird access denied issue with WMI. we're trying to create a diff disk based on a parent vhd in a windows service app that runs under network service (machine account is an admin). everything works fine when we create the diff disk on other machine using wmi - we use an admin user account. however, we cannot do this on a local machine as wmi doesn't take user cred for the local machine. so thought network service account already should have access for this, it seems like it doesn't and even if we run the service under an admin service account, it fails. any pointers???

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  • Fill listview from fragment

    - by Bohsen
    I have a layout file containing a listview that I would like to fill with the help of a Fragment. But it continues to give me errors. The layout file: <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" > <ListView android:id="@+id/list" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_alignParentTop="true" > </ListView> <TableLayout android:id="@+id/details" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_alignParentBottom="true" android:stretchColumns="1" > <Button android:id="@+id/create_patient_button" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="@string/create_patient_button" /> </TableLayout> </RelativeLayout> My fragmentActivity: public class BasicFragmentActivity extends FragmentActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.create_patient_view); FragmentManager fm = getSupportFragmentManager(); Fragment fragment = fm.findFragmentById(R.id.list); if (fragment == null) { FragmentTransaction ft = fm.beginTransaction(); ft.add(R.id.list, new BasicFragment()); ft.commit(); // Make sure you call commit or your Fragment will not be added. // This is very common mistake when working with Fragments! } } } My ListFragment: public class BasicFragment extends ListFragment { private PatientAdapter pAdapter; @Override public void onActivityCreated(Bundle savedState) { super.onActivityCreated(savedState); pAdapter = new PatientAdapter(getActivity(), GFRApplication.dPatients); setListAdapter(pAdapter); } } The error: java.lang.UnsupportedOperationException: addView(View) is not supported in AdapterView

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  • How to copy files from local machine to server using SSH file transfer protocol?

    - by morpheous
    I have an Ubuntu 9.10 desktop machine which I use locally. I am setting up a server on a hosting provider. The server will run a very minimal version of Ubuntu server LTS (only LAMP and email server no GUI). I want to write a script (scheduled as a cron job) that will allow me to upload local files onto the server. I want to use [SFTP][1], for security reasons. I am new to shell scripting - but I guess shell scripting is the way to do this (unless I am mistaken). Can anyone provide me with the initial pointers on how to go about writing such a script, in order to SECURELY upload local files to the server? Ideally, I would like to compress the files before the transfer (to save on bandwidth) [1]: http://SSH file transfer protocol

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  • Troubles moving a UIView.

    - by Joshua
    I have been trying to move a UIView by following a users touch. I have almost got it to work except for one thing, the UIView keeps flicking between two places. Here's the code I have been using: - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { NSLog(@"touchDown"); UITouch *touch = [touches anyObject]; firstTouch = [touch locationInView:self.view]; lastTouch = [touch locationInView:self.view]; [self.view setNeedsDisplay]; } - (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event { InSightViewController *contentView = [[InSightViewController alloc] initWithNibName:@"SubView" bundle:[NSBundle mainBundle]]; [contentView loadView]; UITouch *touch = [touches anyObject]; currentTouch = [touch locationInView:self.view]; if (CGRectContainsPoint(contentView.view.bounds, firstTouch)) { NSLog(@"touch in subView/contentView"); sub.frame = CGRectMake(currentTouch.x - 50.0, currentTouch.y, 130.0, 21.0); } NSLog(@"touch moved"); lastTouch = currentTouch; [self.view setNeedsDisplay]; } And here's what's been happening: http://cl.ly/Sjx

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  • EF in a UserControl can't see the app.config?

    - by Sven
    I just created a user control. This control also makes use of my static Entity Framework class to load two comboboxes. All is well and runs without a problem. Design and runtime are working. Then when I stop the application all the forms that contain my UserControl don't work any more in design time. I just see two errors: Error1: The specified named connection is either not found in the configuration, not intended to be used with the EntityClient provider, or not valid. Error 2: The variable ccArtikelVelden is either undeclared or was never assigned. (ccArtikelVelde is my UserControl) Runtime everything is still working My static EF Repositoy class: public class BSManagerData { private static BSManagerEntities _entities; public static BSManagerEntities Entities { get { if (_entities == null) _entities = new BSManagerEntities(); return _entities; } set { _entities = value; } } } Some logic happening in my UserControl to load the data in the comboboxes: private void LaadCbx() { cbxCategorie.DataSource = (from c in BSManagerData.Entities.Categories select c).ToList(); cbxCategorie.DisplayMember = "Naam"; cbxCategorie.ValueMember = "Id"; } private void cbxCategorie_SelectedIndexChanged(object sender, EventArgs e) { cbxFabrikant.DataSource = from f in BSManagerData.Entities.Fabrikants where f.Categorie.Id == ((Categorie)cbxCategorie.SelectedItem).Id select f; cbxFabrikant.DisplayMember = "Naam"; cbxFabrikant.ValueMember = "Id"; } The only way to make my forms work again, design time, is to comment out the EF part in the UserControl (see above) and rebuild. It's very strange, everything is in the same assembly, same namespace (for the sake of simplicity). Anyone an idea?

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  • Indirect property notification

    - by Carlo
    Hello, this question might look a little trivial, but it might not be. I'm just wondering which of the following two cases is better for indirect property notification, or perhaps there is an even better way. The scenario: I have two properties, the first one is an object called HoldingObject, the second one is a boolean called IsHoldingObject, which is false if HoldingObject == null, otherwise it's true. I'm just wondering what is the best notification mechanism for IsHoldingObject: Case (A) - Notify IsHoldingObject changed from the HoldingObject proeperty: public class NotifyingClass1 : INotifyPropertyChanged { private object _holdingObject; public object HoldingObject { get { return _holdingObject; } set { if (_holdingObject != value) { _holdingObject = value; NotifyPropertyChanged("HoldingObject"); // Notify from the property that is being checked NotifyPropertyChanged("IsHoldingObject"); } } } public bool IsHoldingObject { get { return this.HoldingObject == null; } } #region INotifyPropertyChanged Members public event PropertyChangedEventHandler PropertyChanged; private void NotifyPropertyChanged(string propertyName) { if (this.PropertyChanged != null) this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName)); } #endregion } Case (B) - Notify IsHoldingObject changed from the IsHoldingObject directly, by setting it to false or true from HoldingObject property: public class NotifyingClass2 : INotifyPropertyChanged { private object _holdingObject; public object HoldingObject { get { return _holdingObject; } set { if (_holdingObject != value) { _holdingObject = value; NotifyPropertyChanged("HoldingObject"); // 1) Set the property here this.IsHoldingObject = _holdingObject != null; } } } private bool _isHoldingObject; public bool IsHoldingObject { get { return _isHoldingObject; } set { if (_isHoldingObject != value) { _isHoldingObject = value; // 2) Notify directly from the property NotifyPropertyChanged("IsHoldingObject"); } } } #region INotifyPropertyChanged Members public event PropertyChangedEventHandler PropertyChanged; private void NotifyPropertyChanged(string propertyName) { if (this.PropertyChanged != null) this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName)); } #endregion } I personally lean to the first one because it requires less code, but I'm not sure how recommendable it is to do that. Let me know if there is another (better) way. Thanks!

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  • How to set the the height of cell progamatically without using nib file ?

    - by srikanth rongali
    This is my program - (void)viewDidLoad { [super viewDidLoad]; // Uncomment the following line to display an Edit button in the navigation bar for this view controller. self.title = @"Library"; self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Close" style:UIBarButtonItemStyleBordered target:self action:@selector(close:)]; // self.tableView.rowHeight = 80; } -(void)close:(id)sender { // } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"Cell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:CellIdentifier] autorelease]; UILabel *dateLabel = [[UILabel alloc]init]; dateLabel.frame = CGRectMake(85.0f, 6.0f, 200.0f, 20.0f); dateLabel.tag = tag1; [cell setAccessoryType:UITableViewCellAccessoryDisclosureIndicator]; cell.contentView.frame = CGRectMake(0.0f, 0.0f, 320.0f, 80.0f); [cell.contentView addSubview:dateLabel]; [dateLabel release]; } // Set up the cell... //[(UILabel *)[cell viewWithTag:tag1] setText:@"Date"]; cell.textLabel.text = @"Date"; return cell; } I am setting the frame size of cell in tableView: but the cell is in default size only. I mean the height I set was 80 but it was not set as 80 height. How can I make it. Thank You

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  • MS Exam 70-536 - How to throw and handle exception from thread?

    - by Max Gontar
    Hello! In MS Exam 70-536 .Net Foundation, Chapter 7 "Threading" in Lesson 1 Creating Threads there is a text: Be aware that because the WorkWithParameter method takes an object, Thread.Start could be called with any object instead of the string it expects. Being careful in choosing your starting method for a thread to deal with unknown types is crucial to good threading code. Instead of blindly casting the method parameter into our string, it is a better practice to test the type of the object, as shown in the following example: ' VB Dim info As String = o as String If info Is Nothing Then Throw InvalidProgramException("Parameter for thread must be a string") End If // C# string info = o as string; if (info == null) { throw InvalidProgramException("Parameter for thread must be a string"); } So, I've tried this but exception is not handled properly (no console exception entry, program is terminated), what is wrong with my code (below)? class Program { static void Main(string[] args) { Thread thread = new Thread(SomeWork); try { thread.Start(null); thread.Join(); } catch (InvalidProgramException ex) { Console.WriteLine(ex.Message); } finally { Console.ReadKey(); } } private static void SomeWork(Object o) { String value = (String)o; if (value == null) { throw new InvalidProgramException("Parameter for "+ "thread must be a string"); } } } Thanks for your time!

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  • How to create an iPad directory view like animation?

    - by mahes25
    In the recent iOS 4.2 update, Apple introduced a nice animation for creating one level directories. I am trying to figure out how to implement a similar animation in my project. I would deeply appreciate it if anyone could give me any pointers to do this efficiently. From my investigation, I believe this animation or effect could be done very efficiently using Core Image which would allow me to write a custom filter. Unfortunately, Core Image is not available in iPhone. So how can do it? I read a blog post that explained a core animation scheme to create an iPad flip clock. The problem I have is similar but has important differences. Besides, I not excited about saving the subimage combinations, which I believe can cause a memory issue. Please enlighten me on the possible ways of doing this animation. I am relatively new to iOS programming, so I might have missed obvious ways of doing this animation or effect.

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  • Tomcat application: Frequent OutOfMemory PermGen exception while image uploads

    - by rabbit
    Hi, I have a tomcat 6 application which I have set parameters of -Xms512m -Xmx1024m. I thought 1 GB of memory in a 4 GB RAM would be enough, but that is not the case. On application stop/start multiple times (from tomcat manager) and also on image uploads (sometimes) I run into the OutOfMemory PermGen space error and the site stops responding. Should I increase the memory still some more? Is there anything else that I can do to from the tomcat side so that it does not run into the PermGen space issue? Thanks in advance for pointers/tips etc.

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  • Address book Phone number (+45) prefix causing crash!

    - by CCDEV
    Hi Guys... I am having trouble getting phone numbers from the iPhone Addressbook. There is no problem when the number do not contain a country code prefix like +45, but if it does, my app crashes... Is this a known issue? I haven't been able to find anything about it... Thanks EDIT: I get phonenumber like this: -(void)getContact { ABPeoplePickerNavigationController *pp = [[ABPeoplePickerNavigationController alloc] init]; pp.displayedProperties = [NSArray arrayWithObject:[NSNumber numberWithInt:kABPersonPhoneProperty]]; pp.peoplePickerDelegate = self; [self presentModalViewController:pp animated:YES]; [pp release]; } - (void)peoplePickerNavigationControllerDidCancel:(ABPeoplePickerNavigationController *)peoplePicker { // assigning control back to the main controller [self dismissModalViewControllerAnimated:YES]; } - (BOOL)peoplePickerNavigationController:(ABPeoplePickerNavigationController *)peoplePicker shouldContinueAfterSelectingPerson:(ABRecordRef)person { return YES; } -(BOOL)peoplePickerNavigationController:(ABPeoplePickerNavigationController *)peoplePicker shouldContinueAfterSelectingPerson:(ABRecordRef)person property:(ABPropertyID)property identifier:(ABMultiValueIdentifier)identifier { ABMultiValueRef phoneProperty = ABRecordCopyValue(person,property); saveString = (NSString *)ABMultiValueCopyValueAtIndex(phoneProperty,identifier); saveString = [saveString stringByReplacingOccurrencesOfString:@" " withString:@""]; nummerTextField.text = saveString; }

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  • Progressbar behaves strangely

    - by wanderameise
    I just created an application in C# that uses a thread which polls the UART for a receive event. If data is received an event is triggered in my main thread (GUI) and a progress bar is controlled via PerformStep() method (of course, I previously set the Max value accordingly). PerformStep is invoked using the following expression to handle cross threading this.Invoke((Action)delegate{progressBar2.PerformStep();}) When running this application the progressbar never hits its final value. It stops at 80%. When debugging and stopping at the line mentioned above, everything works fine using single steps. I have no idea what is going one! Start read thread on main thread: pThreadWrite = new Thread(new ThreadStart(ReadThread)); pThreadWrite.Start(); Read Thread: private void ReadThread() { while(1) { if (ReceiveEvent) { FlashProgressBar(); } } } Event that is triggered in main thread: private void FlashProgressBar() { this.Invoke((Action)delegate { progressBar2.PerformStep();}); } (It's a simplified representation of my code) It seems as if the internal progress is faster than the visual one.

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  • SWIG_NewPointerObj and values always being nil

    - by Tom J Nowell
    I'm using SWIG to wrap C++ objects for use in lua, and Im trying to pass data to a method in my lua script, but it always comes out as 'nil' void CTestAI::UnitCreated(IUnit* unit){ lua_getglobal(L, "ai"); lua_getfield(L, -1, "UnitCreated"); swig_module_info *module = SWIG_GetModule( L ); swig_type_info *type = SWIG_TypeQueryModule( module, module, "IUnit *" ); SWIG_NewPointerObj(L,unit,type,0); lua_epcall(L, 1, 0); } Here is the lua code: function AI:UnitCreated(unit) if(unit == nil) then game:SendToConsole("I CAN HAS nil ?") else game:SendToConsole("I CAN HAS UNITS!!!?") end end unit is always nil. I have checked and in the C++ code, the unit pointer is never invalid/null I've also tried: void CTestAI::UnitCreated(IUnit* unit){ lua_getglobal(L, "ai"); lua_getfield(L, -1, "UnitCreated"); SWIG_NewPointerObj(L,unit,SWIGTYPE_p_IUnit,0); lua_epcall(L, 1, 0); } with identical results. Why is this failing? How do I fix it?

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  • Why are controls (null) in awakeFromNib?

    - by fuzzygoat
    This is a follow on from another question regarding why I could not set UIControls in awakeFromNib. The answer to that is that as you can see below the controls are nil in the awakeFromNib, although they are initialised to the correct objects by the time we get to viewDidLoad. I setup the view the same as I always do, should I be doing something different to access them here, the xib(nib) was designed and saved with the current version of Image Builder. CODE: @interface iPhone_TEST_AwakeFromNibViewController : UIViewController { UILabel *myLabel; UIImageView *myView; } @property(nonatomic, retain)IBOutlet UILabel *myLabel; @property(nonatomic, retain)IBOutlet UIImageView *myView; @end . @synthesize myLabel; @synthesize myView; -(void)awakeFromNib { NSLog(@"awakeFromNib ..."); NSLog(@"myLabel: %@", [myLabel class]); NSLog(@"myView : %@", [myView class]); //[myLabel setText:@"AWAKE"]; [super awakeFromNib]; } -(void)viewDidLoad { NSLog(@"viewDidLoad ..."); NSLog(@"myLabel: %@", [myLabel class]); NSLog(@"myView : %@", [myView class]); //[myLabel setText:@"VIEW"]; [super viewDidLoad]; } OUTPUT: awakeFromNib ... myLabel: (null) myView : (null) viewDidLoad ... myLabel: UILabel myLabel: UIImageView Much appreciated ... gary

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  • i integer does not +1 the 1st time

    - by Hwang
    I have a gallery where it will load an image after a previous image is loaded, so every time 'i' will +1 so that it could move to the next image. This code works fine on my other files, but I dunno why it doesn't work for the current file. Normally if I trace 'i' the correct will be 0,1,2,3,4,5,6... etc adding on till the limit, but this files its 'i' repeat the 1st number twice, only it continues to add 0,0,1,2,3,4,5,6...etc The code is completely the same with the other file I'm using, but I don't know why it just doesn't work here. The code does not seems to have any problem. Anyway i can work around this situation? private var i:uint=0; private function loadItem():void { if (i<myXMLList.length()) { loadedPic=myXMLList[i].thumbnails; galleryLoader = new Loader(); galleryLoader.load(new URLRequest(loadedPic)); galleryLoader.contentLoaderInfo.addEventListener(Event.COMPLETE,picLoaded); } else { adjustImage(); } } private function picLoaded(event:Event):void { var bmp=new Bitmap(event.target.content.bitmapData); bmp.smoothing=true; bmpArray.push(bmp); imagesArray[i].addChild(bmp); i++; loadItem(); }

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  • C As Principal Class For Mac App

    - by CodaFi
    So, I've got a c file raring to go and be the main class behind an all-C mac-app, however, a combination of limiting factors are preventing the application from being launched. As it currently stands, the project is just a main.m and a class called AppDelegate.c, so I entered "AppDelegate" as the name of the principal class in the info.plist, and to my complete surprise, the log printed: Unable to find class: AppDelegate, exiting This would work perfectly well in iOS, because the main function accepts the name of a delegate class, and handles it automatically, but NSApplicationMain() takes no such argument. Now, I know this stems from the fact that there are no @interface/@implementation directives in C, and that's really what the OS seems to be looking for, so I wrote a simple NSApplication subclass and provided it as the Principal Class to the plist, and it launched perfectly well. My question is, how could one go about setting a c file as the principal class in a mac application and have it launch correctly? PS, don't ask what or why I'm doing this for, the foundation must be dug. For @millimoose's amusement, here be the AppDelegate.c file: #include <objc/runtime.h> #include <objc/message.h> struct AppDel { Class isa; id window; }; // This is a strong reference to the class of the AppDelegate // (same as [AppDelegate class]) Class AppDelClass; BOOL AppDel_didFinishLaunching(struct AppDel *self, SEL _cmd, void *application, void *options) { self->window = objc_msgSend(objc_getClass("NSWindow"), sel_getUid("alloc")); self->window = objc_msgSend(self->window, sel_getUid("init")); objc_msgSend(self->window, sel_getUid("makeKeyAndOrderFront:"), self); return YES; }

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  • How to avoid concurrent execution of a time-consuming task without blocking?

    - by Diego V
    I want to efficiently avoid concurrent execution of a time-consuming task in a heavily multi-threaded environment without making threads wait for a lock when another thread is already running the task. Instead, in that scenario, I want them to gracefully fail (i.e. skip its attempt to execute the task) as fast as possible. To illustrate the idea considerer this unsafe (has race condition!) code: private static boolean running = false; public void launchExpensiveTask() { if (running) return; // Do nothing running = true; try { runExpensiveTask(); } finally { running = false; } } I though about using a variation of Double-Checked Locking (consider that running is a primitive 32-bit field, hence atomic, it could work fine even for Java below 5 without the need of volatile). It could look like this: private static boolean running = false; public void launchExpensiveTask() { if (running) return; // Do nothing synchronized (ThisClass.class) { if (running) return; running = true; try { runExpensiveTask(); } finally { running = false; } } } Maybe I should also use a local copy of the field as well (not sure now, please tell me). But then I realized that anyway I will end with an inner synchronization block, that still could hold a thread with the right timing at monitor entrance until the original executor leaves the critical section (I know the odds usually are minimal but in this case we are thinking in several threads competing for this long-running resource). So, could you think in a better approach?

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  • UpdatePanel reloads the whole page

    - by Emil D
    Hi.I'm building an asp.net cutom control inside which I have two dropdownlists: companyIdSelection and productFamilySelection.I populate the companyIdSelection at Page_Load and in order to populate the productFamilySelection depending on the selected item in companyIdSelection.I'm using UpdatePanels to achieve this, but for some reason every time I update companyIdSelection Page_Load is being called ( which as far as I know should happen only when the entire page is reloaded ), the list is being reloaded again and the item the user selected is lost( the selected item is always the top one ).Here's the code <asp:UpdatePanel ID="updateFamilies" runat="server" UpdateMode="Always"> <ContentTemplate> Company ID:<br> <br></br> <asp:DropDownList ID="companyIdSelection" runat="server" AutoPostBack="True" OnSelectedIndexChanged="companyIdSelection_SelectedIndexChanged"> </asp:DropDownList> <br></br> Product Family: <br></br> <asp:DropDownList ID="productFamilySelection" runat="server" AutoPostBack="True" onselectedindexchanged="productFamilySelection_SelectedIndexChanged"> </asp:DropDownList> <br> </ContentTemplate> </asp:UpdatePanel> protected void Page_Load(object sender, EventArgs e) { this.companyIdSelection.DataSource = companyIds(); //companyIds returns the object containing the initial data items this.companyIdSelection.DataBind(); } protected void companyIdSelection_SelectedIndexChanged(object sender, EventArgs e) { // Page_Load is called again for some reason before this method is called, so it // resets the companyIdSelection EngDbService s = new EngDbService(); productFamilySelection.DataSource = s.getProductFamilies(companyIdSelection.Text); productFamilySelection.DataBind(); } Also, I tried setting the UpdateMode of the UpdatePanel to "Conditional" and adding an asyncpostback trigger but the result was the same. What am I doing wrong? PS: I fixed the updating problem, by using Page.IsPostBack in the Page_Load method, but I would still want to avoid a full postback if possible

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  • fgets throwing unhandled exception while parsing stl

    - by user3478400
    I am new to c++, I am trying to parse a stl file which is of about 64MB and has about ~18K lines in it. The code works fine for first few 100 lines but then fgets throws following exception: "Unhandled exception at 0x77B0BAC5 (ntdll.dll) in STLparser.exe: 0xC0000024: There is a mismatch between the type of object required by the requested operation and the type of object that is specified in the request." I have checked manually the line for which fgets throws exception, there is nothing out of ordinary there. I am out of options for now. Any help to fix this issue will be greatly appreciated. ================CODE========================== #include<fstream> #include<iostream> #include"ParseString.h" #include"Vectors.h" using namespace std; int main(void) { //Define variables FILE *file; char *line = new char; parsestring oneline; int n_Vols = 0, n_Elms = 0, n_nods = -1, E = 0; Nod *nodes = new Nod(); Nod dummy; Elm *elements = new Elm(); int mycounter = 0; //Open file fopen_s(&file, "sample.stl", "r"); while (fgets(line, 1024, file) != NULL) //**********Getting Error Here************* { // populate required data } fclose(file); printf("%d,%d,%d", n_Vols, n_Elms, n_nods); getchar(); return 0; } ===================When broken, execution resumes at this function (not my function, something internal) void __cdecl _unlock ( int locknum ) { /* * leave the critical section. */ LeaveCriticalSection( _locktable[locknum].lock ); }

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  • Problems with Unity BuildUp Method

    - by Voice
    Hi everybody) I'm using Unity App Block for my project (version 1.2.0.0). I have a problem with Unity Container BuildUp method which I'm using for my ascx controls. Here is some code (that's pretty simple) public class BaseUserControl<T>:UserControl where T:class { protected override void OnInit(EventArgs e) { InjectDependencies(); base.OnInit(e); } protected virtual void InjectDependencies() { var context = HttpContext.Current; if (context == null) { return; } var accessor = context.ApplicationInstance as IContainerAccessor; if (accessor == null) { return; } var container = accessor.Container; if (container == null) { throw new InvalidOperationException("No Unity container found"); } container.BuildUp<T>(this as T); } } This method is called in base control for ascx controls in my solution. And here the property that should be injected in child control: [Dependency] private IStock Stock { get; set; } So after buildup Stock property is still empty. Resolve method works fine for IStock with the same container and configuration. I've tried buildup with simple test class with only one property IStock and got the same result. So what can be wrong with buildup?

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  • GWT + JDO + ArrayList

    - by dvieira
    Hi, I'm getting a Null ArrayList in a program i'm developing. For testing purposes I created this really small example that still has the same problem. I already tried diferent Primary Keys, but the problem persists. Any ideas or suggestions? 1-Employee class @PersistenceCapable(identityType = IdentityType.APPLICATION) public class Employee { @PrimaryKey @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY) @Extension(vendorName="datanucleus", key="gae.encoded-pk", value="true") private String key; @Persistent private ArrayList<String> nicks; public Employee(ArrayList<String> nicks) { this.setNicks(nicks); } public String getKey() { return key; } public void setNicks(ArrayList<String> nicks) { this.nicks = nicks; } public ArrayList<String> getNicks() { return nicks; } } 2-EmployeeService public class BookServiceImpl extends RemoteServiceServlet implements EmployeeService { public void addEmployee(){ ArrayList<String> nicks = new ArrayList<String>(); nicks.add("name1"); nicks.add("name2"); Employee employee = new Employee(nicks); PersistenceManager pm = PMF.get().getPersistenceManager(); try { pm.makePersistent(employee); } finally { pm.close(); } } /** * @return * @throws NotLoggedInException * @gwt.typeArgs <Employee> */ public Collection<Employee> getEmployees() { PersistenceManager pm = getPersistenceManager(); try { Query q = pm.newQuery("SELECT FROM " + Employee.class.getName()); Collection<Employee> list = pm.detachCopyAll((Collection<Employee>)q.execute()); return list; } finally { pm.close(); } } }

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