I'm trying to use a NSProgressIndicator (indeterminate) inside of a statusbar-menu. I'm using an NSView-object as view for the menuitem, and then subviews the progress indicator to display it. But whenever i try to call the startAnimation: for the progress, nothing happens. When i try do the very same thing on a normal NSWindow it works perfectly, just not when inside a menuitem.
I'm new to both cocoa and objective-c so I might've overlooked something "obvious" but I've searched quite a bit for a workaround but without success. I found something about menuitems cant be updated while shown and that you need to use a bordeless window instead. But I have not been able to confirm this in any documentation.
Edit:
Ok, almost works now. When using the setUsesThreadedAnimation: and from a MenuDelegate's menuWillOpen and creating a new thread. This thread runs a local method:
-(void) doWork(NSProgressIndicator*) p{
[p startAnimation:self];
}
This will start the progressindicator on a random(?) basis when opening the menu. If I call startAnimation: directly without going through doWork: (still using a new thread), it never works. Doesn't setUsesThreadedAnimation: make the progress-bar create it's own thread for the animation?
Solved it by using:
[progressIndicator performSelector:#selector(startAnimation:)
withObject:self
afterDelay:0.0
inModes:[NSArray
arrayWithObject:NSEventTrackingRunLoopMode]];
Inside the menuWillOpen:, the problem seems to have been calling startAnimation: before the progressbar was finished drawing itself.
How are you referencing the NSProgressIndicator that is in the view (and the one in the window, for that matter)? For example, do you have a controller class that has IBOutlet's hooked up to the progress indicators? If you are using an IBOutlet, are you sure it's hooked up properly in the nib file?
Also, where and when are you calling startAnimation:? (We need to see some code).
One thing that can sometimes happen is that you forget to hook up an IBOutlet in the nib. Then, when you attempt to tell the object to do something in code at runtime, the IBOutlet is nil, and so what you think is a message being sent to your object is in fact, a message being sent to nil. In other words, it's just ignored, and effectively looks like it's not working.
Provided you do have a (potentially) valid reference to the UI object, the other common issue you'll see is when a developer is trying to send a message to the object at "too early" of a time. In general, init methods are too early in the controller object's lifetime to be able to send messages to user interface objects—those IBOutlet's are still nil. By the time -awakeFromNib is called, IBOutlet's should be valid (provided you hooked them up in IB) and you can then send the message to the UI object.
Have you told it to use threaded animation via -setUsesThreadedAnimation:?
Related
I'm not very sure how Document-Based Applications works.
I've created some actions for NSObject in the Mainmenu.xib. One of this is called when the user click on "File>new":
-(IBAction) newDocument:(id)sender{
Document* newDoc =[[Document alloc] init];
[[NSDocumentController sharedDocumentController]addDocument:newDoc];
[newDoc addWindowController: [[NSWindowController alloc] initWithWindowNibName:[newDoc windowNibName] owner:newDoc]];
[newDoc showWindows];
}
I've also this code inside the openDocument:(id) sender action that does the same but of course loading data to define the application workspace.
If I run the application it show a blank document without to call newDocument action. I don't know how to stop default blank document and to set newDocument: to be called.
Then if i do openDocument: too (so I've two documents, one blank and one not) and I do some operation on the second document it also replicate in the first blank one.
I've double check delegates, file owners, and also if the - (void)windowDidBecomeMain:(NSNotification *)notification return different pointers and all seem to be ok.
Probably I've not understood document based application work flow but I've read the Apple guide and other istructions. What do I miss?
An IBAction method is called, when the user did something. So this is not called from the system at app launch.
You can customize the behavior at app launch with -applicationShouldOpenUntitledFile: (NSApplicationDelegate) and – this is probably your next question – -applicationShouldHandleReopen:hasVisibleWindows: (NSApplicationDelegate). Changing the behavior in both cases is not recommended.
Looking to your action method, I see no reason, why you want to customize it.
A instance of your document class is created automatically.
You can create a window controller for it in your document subclass. This is documented.
Just let NSDocumentController do the work for you. What is the problem of the default behavior?
No. I thought to be confused instead the only problem was about releasing observer notification. When you call the close message for a NSDocument notification observers still persist. Working in ARC I miss this point.
So This is the solution at my issue. Thank you anyway.
I'm updating a UILabel in another view using a method invoked using the NSNotification center.
What I'm finding is that it's not working, the label remains unchanged until the view is reloaded at a later point (not using the method called by nsnotification center).
The label is set to nonatomic, retain and I'm using self to bind everything to that property.
obviously all of the code (the method) that tries to update the label is located in the corresponding viewController. The method gets called (I can see that with NSLog), and all it does is self.label2.text = #"label 2 updated";
I'm able to update the text value of the label using a timer just fine, so I don't think there is a problem with the label, but rather with my understanding of threading and/or what is loaded or not at a given time.
What do you think is the problem?
PS: i WILL chose an answer even if it doesn't help me that much, so please post your wildest guesses!
First make sure that your label is not nil when you set the text.
If it's not nil, try calling setNeedsLayout on your label after setting the text (this shouldn't be necessary). Also, verify that you are on the main thread with:
[NSThread isMainThread]
If that doesn't help, use a subclass of UILabel, override setText and put a breakpoint on it to see what's going on.
I have created a fairly simple screensaver that runs on Mac OS 10.6.5 without issue.
The configuration screen has accumulated quite a few different options and I'm trying to implement my own preview on the configureSheet window so the user (just me, currently) can immediately see the effect of a change without having to OK and Test each change.
I've added an NSView to the configureSheet and set the custom class in Interface Builder to my ScreenSaverView subclass. I know that drawRect: is firing, because I can remove the condition for clearing the view to black, and my custom preview no longer appears with the black background.
Here is that function (based on several fine tutorials on the Internet):
- (void)drawRect:(NSRect)rect
{
if ( shouldDrawBackground )
{
[super drawRect:rect];
shouldDrawBackground = NO;
}
if (pausing == NO)
[spiroForm drawForm];
}
The spiroForm class simply draws itself into the ScreenSaverView frame using NSBezierPath and, as mentioned, is not problematical for the actual screensaver or the built-in System Preferences preview. The custom preview (configureView) frame is passed into the init method for, um, itself (since its custom class is my ScreenSaverView subclass.) The -initWithFrame method is called in configureSheet before returning the configureSheet object to the OS:
[configureView initWithFrame:[configureView bounds] isPreview:YES];
Maybe I don't have to do that? It was just something I tried to see if it was required for drawing.
I eventually added a delegate to the configureSheet to try triggering the startAnimation and stopAnimation functions of my preview via windowWillBeginSheet and windowWillEndSheet notifications, but those don't appear to be getting called for some reason. The delegate is declared as NSObject <NSWindowDelegate> and I set the delegate in the configureSheet method before returning the configureSheet object.
I've been working on this for days, but haven't been able to find anything about how the OS manages the ScreenSaverView objects (which I think is what I'm trying to emulate by running my own copy.)
Does anybody have any suggestions on how to manage this or if Apple documents it somewhere that I haven't found? This isn't really required for the screensaver to work, I just think it would be fun (I also looked for a way to use the OS preview, but it's blocked while the configureSheet is activated.)
OK, there are a couple of 'duh' moments involved with the solution:
First of all, I was setting the delegate for the sheet notifications to the sheet itself. The window that the sheet belongs to gets the notifications.
Secondly, that very window that the sheet belongs to is owned by System Preferences, I don't see any way to set my delegate class as a delegate to that window, so the whole delegate thing doesn't appear to be a viable solution.
I ended up subclassing NSWindow for the configureSheet so that I could start and stop animation on my preview by over-riding the makeKeyWindow and close methods.
- (void) makeKeyWindow
{
if (myPreview != nil)
if ( ! [myPreview isAnimating])
{
[myPreview startAnimation];
}
[super makeKeyWindow];
}
I also had to add an IBOutlet for my preview object itself and connect it in Interface Builder.
Still working out a couple of issues, but now when I click on my screensaver Options button, my configureSheet drops down and displays its own preview while you set options. Sheesh. The hoops I jump through for these little niceties. Anyway, I like it. Onward and upward.
I'm developing simple MVC app in Cocoa/Objective-C. I have a strange issue (or misunderstanding) with notifications and KVO.
I have AppController object in MainMenu.xib, hence I implement awakeFromNib method where I register for NSImageView changing its image property. I add self as an observer in the following way:
// options:3 equals to new/old passed values in changeDictionary
[backgroundImageView addObserver:self
forKeyPath:#"image"
options:3
context:NULL];
The backgroundImageView is an IBOutlet in AppController connected to NSImageView.
In standard observeValueForKeyPath:ofObject:change:context method I just log the received notification.
Problem is - when i change the image value of NSImageView I get 3 notifications instead of one. Can you help me with this? Maybe I'm overlooking something in options or in generally registering observer?
UPDATE: backgroundImageView is the instance of BackgroundImageView class which is sublcass of NSImageView. I subclassed the latter one for handling drag and drop operations as drag destination. When performDragOperation: is called (the last 'state' of the dragging) it changes the value for image property with setImage between willChangeValueForKey and didChangeValueForKey.
… it changes the value for image property with setImage between willChangeValueForKey and didChangeValueForKey.
When you send an accessor message, you get KVO notifications for free with it. You should remove the {will,did}ChangeValueForKey: messages, because they're the cause of at least one of the extraneous change notifications.
Is your AppController the File's Owner of two other nibs? If so, it'll receive an awakeFromNib message for each of those, too. MainMenu plus two makes three awakeFromNib messages, which means you'll add yourself as an observer three times.
There does not seem to be any obvious problem with setting of the observer.
Have a look at how you update the image that you observe, maybe it's being modified 3 times?
I'm working on a simple proof-of-concept for an iPhone app (and important bit of info, I'm pretty new to Mac OSX development all around). I created a view based app with a timer. I declared my NSTimer in the interface of my app's controller, used #property and #synthesize, and I initialize it in the controller's viewDidLoad method with scheduledTimerWithTimeInterval method. My selector is a method with the signature -(void)someMethod:(NSTimer *)timer which is declared in the interface and defined in the implementation file of the controller as well. I can step past the line where I assign the timer and see that it points to a valid object, but my program goes no further than the end of the viewDidLoad method and never reaches the breakpoint at the first line of my method that is called by the timer. Also, I see GDB: Program received bad signal: "EXC_BAD_ACCESS" in the status bar of xcode at this point (viewDidLoad end is reached). I didn't do anything in IB but add a view and a picker just so I'd see if the UI actually loads...it never does.
So, am I doing something wrong with the NSTimer, or are my troubles elsewhere? How can I use the debugging tools in xcode to get more information?
EXC_BAD_ACCESS usually indicates a memory management error, without seeing the code probably from somewhere else in your app. It's a very common error for beginners, but an important subject to fully understand, so I'd suggest looking through some of the questions on memory management here and find a few guides or tutorials to look through. It's actually pretty easy to learn.
Also, it shouldn't hurt but unless you need to access the timer in between fire events, you don't actually need to store it as an instance variable. Once you create and start a timer it's added to and retained by the application's run loop.
Have you got NSZombieEnabled?
Might be useful if this is failing on an over released object.