How to refer to Cocoa controls located in in the same NSWindow? - cocoa

I have a NSWindow with an NSView and an NSTextField inside.
I'm using Interface builder right now. I have dropped the two controls on the default NSWindow and subclassed an NSView. I'm implementing the -drawRect method from NSView and I need to access to the content of NSTextField.
How do I refer to the instance of NSTextField from a method inside the NSView ?

Your NSWindow is (or should be) controlled by a window controller. In IB you create an outlet for the NSTextField in your window controller. Using the outlet, you can then refer to the NSTextField:
In your window controller .h file:
#property (strong) IBOutlet NSTextField *myTextField;
In your window controller .m file:
#synthesize myTextField;
From there you can in your controller:
[[self myTextField] setEditable: NO];
A point to note is that you do not access the controls in a window directly from that window as windows (and all Cocoa controls for that matter) are statically stored in a XIB/NIB file. All access to controls (UI elements) is channelled through controllers (NSWindowController, NSViewController) which in turn are capable of loading XIB/NIB files.
Apple provides various samples in their docs on how to do this.

Related

NSViewController subclass object is loaded, but its widgets are not loaded into its NSView

I have created a custom view that is intended to be loaded in some different windows. ActionWidgets is a subclass of NSViewController, complete with its own xib file and its own widget contents.
In a window where it is used, I have created an object for it with Interface Builder, and I've carefully set its xib file and its connections, to both its NSView widget in that window, and to an ActionWidgets IBOutlet variable in the window's owner class.
But the ActionWidgets widgets don't get loaded into that NSView widget, despite all that I've tried. Its methods awakeFromNib() and viewDidLoad() get called, and nibName has the right nib name, so it ought to work.
What else might I need to do?

Can I use NSViewController to provide a reusable NSTableView with defined columns and data?

I'm fairly new to Xcode and Cocoa development, so please excuse me if I use the wrong terminology.
I have a window which has an NSTableView bound to a NSArrayController. The NSTableView has some predefined columns and the NSArrayController is populated with data when my window is loaded.
This all works fine, but I now need to re-use the functionality in a number of other windows.
After much reading I think and NSViewController is what I need, to provide an object that I can re-use in different windows in multiple .xib.
So what I have done is created a new NSViewController sub class in Xcode which also created a new xib for that controller.
The xib contains a custom view, where I have placed my NSTableView.
#interface KeyViewController : NSViewController
#property (weak) IBOutlet NSTableView *keyTable;
#end
The files owner class is set to the KeyViewController, and the view outlet is set to the files owner.
I then placed a ViewController object into the original window and hooked up the view to a new custom view in the window
I then set the nib name for the ViewController in its properties.
The new view never gets displayed and the view controller initWithNibName never gets called.
Am I missing something vital or missing the plot completely. Should you be able to do this just with interface builder or do I need to alloc and init the view in code?
If I do have to do it in code, whats the purpose of the ViewController object in IB and the Nib Name property for it?
Thanks..

NSWindowController object linkage in Interface builder

I created a NSWindow xib file that I want to open on click of a button in another window.
Now, to control the behavior of the NSWindow, I dragged an object from Library in xib and changed it to subclass of NSWindowController (i.e. ListingWindowController) that I defined in XCode.
Similarly I also created a subclass of NSViewController (i.e. ListingViewController) to manage the NSView inside the NSWindow. To do this, I dragged NSViewController from Library in xib and changed its class to ListingViewController.
#class ListingViewController;
#interface ListingWindowController : NSWindowController {
IBOutlet ListingViewController *listingVC;
}
#property (nonatomic, retain) IBOutlet ListingViewController *listingVC;
#end
I connected window and listingVC of my window controller in IB.
Now to invoke this window on click of a button in my launch (first) window, I create the window controller using initWithWindowNibName like this..
- (IBAction) pushConnect:(id)sender {
NSLog(#"Connect pushed.");
if (wc == nil) {
wc = [[ListingWindowController alloc] initWithWindowNibName:#"ListingWindow" owner:self];
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(closeWindow:) name:NSWindowWillCloseNotification object:nil];
[wc showWindow:sender];
}
}
The problem is that despite all the bindings done in IB for the view controllers of upcoming window/view, the window and listingVC comes out to be (null), (null) even after the new window has loaded (below code).
- (void)windowDidLoad {
[super windowDidLoad];
NSLog(#"windowDidLoad = %#, %#", self.window, self.listingVC);
}
Please help why the connections are not working. I'm banging my head against this problem for quite a while now.
PS: I'm coming from iOS programming background. So, I'm assuming the Mac's window/view controller behave similar to iOS UIViewControllers.
TIA..
Note that:
wc = [[ListingWindowController alloc] initWithWindowNibName:#"ListingWindow" owner:self];
means that self (it’s not clear what self is from your question) is the owner of ListingWindow.nib. This means that self is the one who keeps outlets to objects in that nib file, and self is responsible for releasing the top-level objects in the nib file. This also means that you’re creating an instance of ListingWindowController in your code and another instance inside your nib file since you’ve dragged an object of class ListingWindowController onto the nib file.
This is not how it’s supposed to be.
In the vast majority of cases, a window (view) controller loads a nib file and becomes its owner. It has a window (view) outlet that must be linked to a top-level window (view) in the nib file. Being the nib file’s owner, it must have been created before the nib file is loaded.
In order to achieve this for your window controller, you need to set the file’s owner class to ListingWindowController. You must not drag an object cube and instantiate the window controller inside the nib file. The window controller is the owner of the nib file, so it must exist before the nib file is loaded. You must also link the window outlet in file’s owner to the top-level window object in the nib file so that the window controller is aware of what window it should manage.
Having done that, use:
wc = [[ListingWindowController alloc] initWithWindowNibName:#"ListingWindow"];
instead of:
wc = [[ListingWindowController alloc] initWithWindowNibName:#"ListingWindow" owner:self];
since wc is supposed to be the owner of the nib file.
View controllers work similarly. They’re created before loading the nib file, are responsible for loading a nib file that contains a view as a top-level object, are that nib file’s owner, and have a view outlet that must be linked to that top-level view.
It’s not clear from your question whether you have a separate nib file for the view. If you don’t, then using a subclass of NSViewController is not needed at all — you could use a subclass of NSObject instead. If you insist on using NSViewController to manage a view that’s not loaded from a separate nib file, then you should override -loadView so that you get a reference to the view by some means other than loading it from a nib file, and sending it -setView: so that it is aware of the view it’s supposed to be managing.
Recommended reading: Nib Files in the Resource Programming Guide, NSWindowController class reference, NSViewController class reference.

Reference to subclassed NSWindowController returns its document - is this correct?

I am new to document-based applications and hence I may have missed something fundamental. I have written a document based application which uses a subclassed NSWindowController for the interface and a subclassed NSDocument for the model. Per the documentation I initialise the windowController in makeWindowControllers and load its xib. In interface builder, the xib has my windowController subclass set as File's Owner. Among the views in the window, I have a subclass of NSOutlineView and the NSOutlineView datasource and delegate are also refenced in the nib and connected to the windowController via IBOutlets.
According to the documentation, I should be able to access the document from the OutlineView datasource via [windowController document]. However, referencing the windowController (via IBOutlet) from the OutlineView datasource gives me the document instead!
This has lead to some rather ugly code in the OutlineView datasoure (which is a subclass of NSObject in the windowController's xib) to get hold of the document, eg:
-(MyDocument *)myDocument {
MyDocument *theDocument = (MyDocument *)myWindowController;
return theDocument;
}
Where the IBOutlet in the header file references myWindowController as:
IBOutlet MyWindowController *myWindowController
In brief - why does an IBOutlet connected to the windowController get me the document directly instead in this situation? The above code works but seems as if it shouldn't.
Edit: clarification
Okay, I worked out the answer to this one - don't accidentally set the File's Owner of the xib to the NSDocument instead of the windowController in another part of your code and forget that you did it! This overrides the File's Owner that you previously set in the xib.

Is it possible to access the NSControl on a NSWindow using tag?

Is it possible to access the NSControl on a NSWindow using tag?
I used the code below but it warned
NSWindow may not response to viewWithTag
NSButton *a=(NSButton * )[self.window
viewWithTag:tag];
Welcome any comment
Thanks
interdev
Unlike UIWindow in Cocoa Touch, NSWindow does not inherit from NSView, and thus does not implement that method. You probably want to get the contentView of the window, and then look up the tag on that.
Create an NSView in your .h file called 'view'.
In IB, highlight the View under the Window and connect it to the 'File's Owner' view from step 1.
Then you can use viewWithTag.
file.h
#property (strong, nonatomic) IBOutlet NSView * view;
file.m
[(NSTextField*)[self.view viewWithTag:(1)] setStringValue: #"MyStringName"];

Resources