XCODE, dealloc called only after removeFromSuperView - xcode

I have xib, h and m files for custom view, subclass of UIView. I add this custom view to UIVIewControlloer's view. But when I call
[self.navigationController popViewControllerAnimated:YES];
UIViewController's dealloc method calls, but dealloc method os custom view - not. If I remove custom view from controller's view (removeFromSuperview),
both methods calling. I have no idea why ...

In method in custom class was passed UIView as Strong param. Change to weak and everything is ok now.

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?

Make compiler aware of NSView subclass methods when building ViewController's view programmatically

I have created a subclass of NSView that allows me to easily change the background color via the method - (void)setBackgroundColor:(NSColor *)aBackgroundColor.
I want my view controller's main view to be this subclass, so I initiate it with self.view = [[BetterNSView alloc] initWithFrame....
On the next line, I try to set its background color: [self.view setBackgroundColor:[NSColor greenColor]]. But the compiler complains, saying that NSView doesn't have the method setBackgroundColor.
To solve this, I need to use typecasting: [(BetterNSView *)self.view setBackgroundColor:[NSColor greenColor]];. That works. But I'd like to not need the typecasting.
How do I tell the compiler that the view property of the view controller is the BetterNSView subclass? Remember, I'm not using IB.
You have two reasonable choices.
Make an accessor on your view controller with the right type that just passes through to the view property.
Deal with the typecast.
Really, this is one of this situations where typecasting is okay.

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.

Call IBAction in different class

My document based application has a window with a tableview. The tableview has a datasource which points to a class of type NSObject (called HopBill) which includes a NSMutableArray (aHopBill) and the needed tableview methods. So far so good.
For adding rows to the tableview I've added a sheet which is controlled from a NSWindowController (called HopBillSheetController). When pressing the OK button in the sheet. I actually need to do two IBActions (which is not possible): Add the row to the array of the tableview and close the sheet. I can connect the OK button in the sheet to the NSWindowController (to close the sheet) or connect it to the NSObject (to add the row to the array). But I want both :-)
Is it possible to call the IBAction in the NSWindowController from the NSObject? Or is there another way to do this?
I'm quite a beginner to Cocao and Objective-C, so please be gentle :-)
If your sheet is a nib/xib with an NSPanel, the call to close it is simply [panel close]; Assuming your window controller has a property for the panel, you can put the close code at the end of its row-adding IBAction. Or you could have the IBAction itself call another method if you prefer.
If your panel is running modal, you might need to stopModal too. (That's what's needed if everything stays frozen after the panel closes; otherwise never mind.)
Assuming hopBill, your data source, is a property of the window controller, any IBAction you write in the window controller also has access to hopBill; it can do everything you need.
So add a single IBAction to the window controller and connect the panel's OK button to it. That ought to work.
As for calling an IBAction from somewhere other than a control in a nib, yes, you can do that. Use a reference to the control as the sender arg, or nil if the IBAction doesn't use the sender arg.
You could also create your panel programmatically, or use NSAlert. But it sounds like your current setup is simpler -- and therefore better.
Take a look at this h file for an app controller: Apple's ClockControl example
The NSMutableArray *appointments property is the actual data source that will be used by the NSTableViewDataSource protocol methods. The IBAction "addAppointment" can access "appointments" directly: [self.appointments addObject:whatever atIndex:whatever];
The ClockControl example could be modified to use HopBill. You would import its declarations up top: #import "HopBill.h" And then instead of the "appointments" property, it would declare HopBill *hopBill; And "addApointment" would access HopBill's mutable array (aHopBill) like this: [self.hopBill.aHopBill addObject:whatever atIndex:whatever];
Why you can’t send messages to hopBill:
First, because although you declare it, you never initialize it. You have:
HopBill *hopBill;
[self.hopBill.aHopBill addObject: bHopAdditionAtInit];
It should be:
HopBill *hopBill = [[HopBill alloc] init];
[hopBill.aHopBill addObject: bHopAdditionAtInit]; // “self” won’t work here
Second, you’re declaring it inside an IBAction method, (doneHopBillSheet:), so it’s a local variable, accessible only within that method. If HopBill is holding your table’s data source cache, it should be a property of the controller which implements the NSTableViewDataSourceProtocol methods.
In your HopBill interface, you declare the aHopBill array to be a property, and you initialize it in HopBill’s init method (you should also release it in HopBill’s dealloc method). You need to do the same thing for the controller — it should have an instance of HopBill as a property, and that instance should be initialized in the controller’s init method.
If you want HopBillController to manage the tableview, its interface declaration should look like this:
#interface HopBillSheetController : NSWindowController <NSTableViewDelegate, NSTableViewDataSource> {
…
}
And, then, of course, you have to implement the relevant NSTableViewDelegate and NSTableViewDataSource methods.
Also, the controller must have an IBOutlet property for the tableview itself, and in the controller’s awakeFromNib method, it has to assign itself as delegate and datasource:
[self.tableview setDelegate:self];
[self.tableview setDataSource:self];
(The self-dot syntax assumes you’ve set up #property and #synthesize code for tableview.)
The IBAction method that adds items to your table must be in that controller class, or in a class that has a property which is an instance of the controller class. Then the IBAction method will have access to the aHopBill array and can add the new object to the array, after which it will call [tableView reloadData], which will in turn trigger the tableview protocol methods and update the table.
Now, that means that the xib containing the tableview has to have the controller as its file’s owner. Since you’re using NSDocument, I suspect that, instead, you would put the tableview outlet in the NSDocument subclass. And you would give that doc subclass a property which is an instance of the controller. The IBAction methods would also be in the doc subclass, and so they would have access to the controller and its HopBill property. Or maybe you would simply make the doc subclass the controller, rather than using the separate HopBillSheetController class. I’m not sure about the NSDocument stuff. But, remember, the IBAction method can itself call other methods, as long as it has access to instances of the classes in which those methods are declared.
Apple has an example using both the tableview delegate and datasource protocol methods. Go to this link and download the sample code: tableview example
It looks like a nice app. Good luck.

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