deriving from NSTabViewItem - cocoa

I'm writing a Cocoa app. One dialog has 3 tabs, some of the tabs needs more loading time, so I want to load them lazily. Since each Tab is a NSTabViewItem class, so I'm trying to derive from it and overriding its view property. In the view getter method, I use a ViewController to load a view and returns out. In Debugging, I found NSTabViewItem -view method is get called correctly, but after that NSTabView tries to set Initial FirstResponder and crashed with message:
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'In -[NSTabViewItem setInitialFirstResponder:], the first responder must descend from the tab view item's view. (Item: Invalid responder: )'
I tried to override the -initialFirstResponder method to return a sub-view of my loaded view, but it still crashes the same place.
does anyone know how to get it work correctly? Also is it correct way to do this by deriving the NSTabViewItem?
thanks!
-Jonny

OK, I understand the exception now. The NSTabViewItem has its view, so I should use its view and add my new view as a subview, like:
-(NSView*)view {
NSView* view = [super view];
NSVIew* myView = //load view from nib
[view addSubView:myView];
return view;
}

Related

IBAction not triggering NSView drawing

I'm missing something fundamental about NSView. I have a Cocoa Application with an Objective C class named DataSource that is just a regular class, it's not in the nib. The data source has a single instance variable, an NSColor *, and it has a getter and setter.
The view class instantiates the DataSource in awakeFromNib:
- (void)awakeFromNib{
NSLog(#"awakeFromNib");
ds = [[DataSource alloc] init];
}
and then queries the DataSource for the color to use in drawRect. It works fine. I also implement
- (void)mouseDown:(NSEvent *) anEvent;
in the view class, change the color of the DataSource, and then call
[self setNeedsDisplay:YES];
and it also works as I expect when I click in the custom view.
But if I hook up a button in the nib, wired to this IBAction in the view class:
- (IBAction)buttonPushed:(id) sender {
NSLog(#"buttonPushed");
[ds setData:[NSColor cyanColor]];
[self setNeedsDisplay:YES];
}
the data source updates, but drawRect is never called, despite setNeedsDisplay. In my more complicated version, if I click in the view (in a way that doesn't change the color), I will then get the update (caused by the button). Something is delaying drawing. How can I fix this?
Update: There is no controller and there are no outlets. The NSView subclass contains buttonPushed. The data source updates immediately upon button push, but drawing is delayed, despite calling setNeedsDisplay:YES from the view class. Drawing is delayed indefinitely, unless something else happens to trigger it.
Where is the IBAction located? Are you using some view controller? Is the NSView an outlet in that controller?

App crashes when chiledviewcontroller button clicked

am creating a ipad application where i need to show a ChildViewController inside a ParentViewController's View with below code its working perfect.
- (void)viewDidLoad
{
FavViewController *aViewController = [[FavViewController alloc] initWithNibName:#"FavViewController" bundle:nil];
[self.mainView addSubview:aViewController.view];
[super viewDidLoad];
}
When this favViewController load into the self.MainView of parent view all controls inside childViewController showing ok but when i click on UIButton the app is crashing. below is log for the crash.
Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSConcreteMapTable myAction:]: unrecognized selector sent to instance 0x8093170'
*** First throw call stack:
(0x1733012 0x1558e7e 0x17be4bd 0x1722bbc 0x172294e 0x156c705 0x4a02c0 0x4a0258 0x561021 0x56157f 0x560222 0x4cfb1d 0x4cff02 0x4add4a 0x49f698 0x25fddf9 0x25fdad0 0x16a8bf5 0x16a8962 0x16d9bb6 0x16d8f44 0x16d8e1b 0x25fc7e3 0x25fc668 0x49cffc 0x255d 0x2485 0x1)
libc++abi.dylib: terminate called throwing an exception
This is a memory management bug caused by misuse of UIViewControllers.
The FavViewController created in your -viewDidLoad is not retained and so will be deallocated shortly after you leave that method.
You have created a view with a controller, bound actions from controls inside that view to the controls, allowed the controller to be destroyed, and then attempted to fire one of those actions by tapping on a button.
The error you see is because an instance of NSConcreteMapTable now happens to occupy the memory space that once contained your FavViewController.
In addition you are expected not to arbitrarily nest views which belong to UIViewController subclasses like that. If you need to do so you should be using the "container view controller" methods to manage those child controllers. - addChildViewController: is one of those methods and happens to solve the problem because the parent view controller now retains a reference to the child controller so it will not be deallocated.

Cocoa: setters in an NSViewController view

I'm using an NSViewController class with a single view in it to display a progress indicator bar and some text fields. I'm trying to use progressIndicator setMaxValue:and theTextField setStringValue: but neither of these are doing anything.
I've done this before and I've checked and rechecked, it's fairly straightforward, the fact that it's not working makes me think that it has to do with the fact that the class is NSViewController. Which is why I tried
Timers *aTimer = [[Timers alloc] init];
[aTimer.timerNameLabel setStringValue:#"name"];
[aTimer.progressIndicator setMaxValue:x];
in the app delegate which is an NSObject class, but that didn't work either.
I've tried looking around the NSViewController documentation but I can't find anything that says it can't set those values so I don't know what's happening. What am I doing wrong?
You probably want to use -initWithNibName:bundle: instead of a regular init to initialize your custom nib.
EDIT: It seemed the problem was due to the view not being queried before getting other objects. By calling [myController view] you actually load the nib, which isn't done automatically when you initialize the view controller. So before you can use any element of the view, you need to call [myController view]

View is null in viewDidLoad

I created UITabBarController with each tab contain UINavigationController and set rootviewcontroller in this UINavigationController, all of this is done in interface builder. In viewDidLoad I try to get frame size from view, but when I reference view it return null. Have anyone experienced this before.
All IBoutlet are properly connected.
viewDidLoad returning a nil view if the view is connected in your .xib could mean:
For programmatic initialisation (custom controllers):
You forgot to call initWithNibName:bundle: on the view controller class altogether (you may have called init or something instead).
You've overridden the loadView method in your view controller class, but it doesn't set the view.
For all controllers:
An outlet connection hasn't been made correctly.
You have accidentally released the view or view controller before showing it.
The nibName parameter was not properly specified when initialising the view (the nib could not be found or one without a view was found.. though this should also throw an exception).
There wasn't enough memory to allocate the view (the app would likely have been terminated by that point though).
I'd recommend you try doing frame size calculations in viewWillAppear: instead and see if the view is still nil at that point.

In NSWindowController subclass, [self document] returns null

I am using a custom subclass of NSDocument and a custom subclass of NSWindowController. The problem is that I cannot reference my custom document from my custom window controller.
In IB, in the TKDocument NIB I have File's Owner set to TKWindowController.
In my TKDocument subclass I have:
- (void) makeWindowControllers {
TKWindowController *controller = [[TKWindowController alloc] init];
[self addWindowController:controller];
}
Then in my TKWindowController subclass I overrode setDocument to make sure it was being called:
- (void) setDocument(NSDocument *) document {
NSLog(#"setDocument:%#", document);
[super setDocument:document];
}
and then (again in TKWindowController) my action which references the document itself:
- (IBAction) plotClicked:(id) sender {
TKDocument *doc = [self document];
NSLog(#"plotClicked %#", doc);
}
The NSLog in setDocument outputs the string returned by my [TKDocument description] override as I'd expect; I only put it there to see if it was being called. However, doc in plotClicked is null.
What might I have done wrong?
EDIT: I believe the problem is to do with NIBs. My Document has its own NIB with File's Owner set to the custom controller as mentioned above. The plotClicked action is fired from a menu item in MainMenu.xib. I believe it's hitting a new instance of the controller which isn't associated with the current, active document.
So, how do I link the two? My question is really this: How do I obtain a handle to the current active document (or its windowcontroller) from MainMenu.xib?
Thanks
My Document has its own NIB with File's Owner set to the custom controller as mentioned above.
The File's Owner of a document nib should be the document. Consider that suspect #1.
The plotClicked action is fired from a menu item in MainMenu.xib. I believe it's hitting a new instance of the controller which isn't associated with the current, active document.
Did you put a window controller inside your main menu nib? If not, then that isn't the problem, since you must have wired up your plotClicked: menu item to the First Responder, and the window controller and its document will be in the responder chain.
If you did, then there's the solution: delete the window controller from the MainMenu nib and hook up your menu item to the First Responder, so that the action message goes down the responder chain, which will enable it to hit the document or window controller.
How do I obtain a handle to …?
The only Handles on the Mac come from Carbon; those Handles do not exist in Cocoa.
init is not a designated initializer of NSWindowController. You want one of these: – initWithWindow:, – initWithWindowNibName:, – initWithWindowNibName:owner:, or – initWithWindowNibPath:owner:.
Also, from the docs:
In your class’s initialization method,
be sure to invoke on super either one
of the initWithWindowNibName:...
initializers or the initWithWindow:
initializer. Which one depends on
whether the window object originates
in a nib file or is programmatically
created.

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