I am developing an application in XCode 4.6.
To get text-change notifications from NSTextField controls I:
Put NSTextField control on window.
Connect control delegate to File's Owner via right-click in IB, drag from delegate to File's Owner.
Implement controlTextDidChange in window class.
For the application, the window class is my AppDelegate and File's Owner is NSApplication. For the modal dialog, the window class an NSWindowController and File's Owner is of the same type.
If I put a breakpoint in controlTextDidChange, in the AppDelegate class, it never fires. If I do the same procedure with a modal dialog it works fine.
I know in the main application window case the delegate for the control is not my AppDelegate.
What am I doing wrong in hooking up my control delegate in the main window? I must be missing something simple. Is File's Owner the correct delegate to set for controls?
Any help would be appreciated.
Here is some code as requested.
// AppDelegate.h
// SimpleApplication
#import <Cocoa/Cocoa.h>
#import "SimpleTest/SimpleTest.h"
#interface AppDelegate : NSObject <NSApplicationDelegate>
#property (assign) IBOutlet NSWindow *window;
#property (assign) IBOutlet NSTextField *textField;
#end
// AppDelegate.m
// SimpleApplication
#import "AppDelegate.h"
#implementation AppDelegate
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
// Not much to do here for now.
}
// Breakpoint set in this function never fires.
- (void)controlTextDidChange:(NSNotification *)obj
{
NSMutableString* description= [[NSMutableString alloc] init];
id aDelegate= [_textField delegate];
Class delegateClass= [aDelegate class];
[description setString:[delegateClass description]];
[description release];
}
// To provide some information about the delegates.
- (IBAction)textChange:(id)sender
{
NSTextField* theTextField= (NSTextField*)sender;
NSMutableString* description= [[NSMutableString alloc] init];
id aDelegate= [theTextField delegate];
Class delegateClass= [aDelegate class];
[description setString:[delegateClass description]];
[description release];
}
#end
Here is a shot of the right-click information for the NSTextField on the main window -
Identity inspector shows File's Owner as NSApplication, which is what I see in the debugger when I put a breakpoint in textChange and hit return in the text field. However, self, the implementor of controlTextDidChange, is AppDelegate. By contrast, in a modal dialog, self and File's Owner are the same object, derived from NSWindowController.
So, the upshot is that I do not have the correct delegate assigned to the control in the main window - how do I do that?
Can you post some code?
When using delegates make sure you specify that a class implements the required protocol.
#interface MyClass : NSObject <SomeProtocol>
Also make sure you are creating a property to store the delegate.
#property (strong, nonatomic) id<SomeProtocol> delegate;
RE this:
Note that although NSControl defines delegate methods, it does not
itself have a delegate. Any subclass that uses these methods must have
a delegate and the methods to get and set it. In addition, a formal
delegate protocol NSControlTextEditingDelegate Protocol also defines
delegate methods used by control delegates.
...
These include: controlTextDidBeginEditing:, controlTextDidChange:, and controlTextDidEndEditing:
Oh, wow - in adding more detail to my question, I think I figured out the answer. Instead of dragging from text field delegate to File's Owner, just drag to the blue cube that represents App Delegate!
Related
I followed the advice here on how to setup a MainWindowController: NSWindowController for my project's single window. I used a Cocoa class to create the .h/.m files, and I checked the option Also create .xib for User Interface. As a result, Xcode automatically hooked up a window, which I renamed MainWindow.xib, to my MainWidowController.
Next, I deleted the window in the default MainMenu.xib file (in Interface Builder I selected the window icon, then I hit the delete key). After that, I was able to Build my project successfully, and my controller's window in MainWindow.xib displayed correctly with a few buttons on it.
Then I tried adding an NSTableView to my MainWindowController's window. In Xcode, I dragged the requisite delegate and datasource outlets for the NSTableView onto File's Owner, which is my MainWindowController, and I implemented the methods in MainWindowController.m that I thought would make the NSTableView display my data:
- tableView:viewForTableColumn:row:
- numberOfRowsInTableView:
Now, when I Build my project, I don't get any errors, but the data doesn't appear in the NSTableView.
My code is below. Any tips are welcome!
//
// AppDelegate.h
// TableViews1
//
#import <Cocoa/Cocoa.h>
#interface AppDelegate : NSObject <NSApplicationDelegate>
#end
...
//
// AppDelegate.m
// TableViews1
//
#interface AppDelegate ()
#property (weak) IBOutlet NSWindow *window;
#property (strong) MainWindowController* mainWindowCtrl;
#end
#implementation AppDelegate
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification {
// Insert code here to initialize your application
[self setMainWindowCtrl:[[MainWindowController alloc] init] ];
[[self mainWindowCtrl] showWindow:nil];
}
- (void)applicationWillTerminate:(NSNotification *)aNotification {
// Insert code here to tear down your application
}
#end
...
//
// MainWindowController.h
// TableViews1
//
#import <Cocoa/Cocoa.h>
#interface MainWindowController : NSWindowController
#end
...
//
// MainWindowController.m
// TableViews1
//
#import "MainWindowController.h"
#import "Employee.h"
#interface MainWindowController () <NSTableViewDataSource, NSTableViewDelegate>
#property (strong) NSMutableArray* employees;
#property (weak) IBOutlet NSTableView* tableView;
#end
#implementation MainWindowController
- (NSView*)tableView:(NSTableView *)tableView
viewForTableColumn:(NSTableColumn *)tableColumn
row:(NSInteger)row {
Employee* empl = [[self employees] objectAtIndex:row];
NSString* columnIdentifier = [tableColumn identifier];
//The column identifiers are "firstName" and "lastName", which match my property names.
//You set a column's identifier by repeatedly clicking on the TableView until only
//one of the columns is highlighted, then select the Identity Inspector and change the column's 'Identifier' field.
NSString* emplInfo = [empl valueForKey:columnIdentifier]; //Taking advantage of Key-Value coding
NSTableCellView *cellView =
[tableView makeViewWithIdentifier:columnIdentifier
owner:self];
NSLog(#"The Table view is asking for employee: %#", [empl firstName]);
[[cellView textField] setStringValue:emplInfo];
return cellView;
}
- (NSInteger)numberOfRowsInTableView:(NSTableView *)tableView {
return [[self employees] count];
}
- (void)windowDidLoad {
[super windowDidLoad];
// Implement this method to handle any initialization after your window controller's window has been loaded from its nib file.
Employee* e1 = [[Employee alloc] initWithFirstName:#"Joe" lastName:#"Blow"];
Employee* e2 = [[Employee alloc] initWithFirstName:#"Jane" lastName:#"Doe"];
[self setEmployees:[NSMutableArray arrayWithObjects:e1, e2, nil]];
//Test to see if the employees array was populated correctly:
Employee* e = [[self employees] objectAtIndex:0];
NSLog(#"Here is the first employee: %#", [e firstName]);
//I see the output: "Here is the first employee: Joe"
}
- (id)init {
return [super initWithWindowNibName:#"MainWindow"];
}
- (id)initWithWindowNibName:(NSString *)windowNibName {
NSLog(#"Clients cannot call -[%# initWithWindowNibName] directly!",
[self class]
);
[self doesNotRecognizeSelector:_cmd];
return nil;
}
#end
...
//
// Employees.h
// TableViews1
#import <Foundation/Foundation.h>
#interface Employee : NSObject
#property NSString* firstName;
#property NSString* lastName;
- initWithFirstName:(NSString*)first lastName:(NSString*)last;
#end
...
//
// Employees.m
// TableViews1
//
#import "Employee.h"
#implementation Employee
- (id)initWithFirstName:(NSString *)first lastName:(NSString *)last {
if (self = [super init]) {
_firstName = first; //I read that you shouldn't use the accessors in init methods.
_lastName = last;
}
return self;
}
#end
File's Owner(=MainWindowController) connections:
NSTableView connections:
Response to comments:
Here is why calling [self tableView] reloadData] at the end of -windowDidLoad, as suggested in the comments, didn't work:
My _tableView instance variable--created by my #property declaration in MainWindowController.m--doesn't point to anything; therefore calling:
[[self tableView] reloadData]
I think is equivalent to calling:
[nil reloadData]
which doesn't do anything.
I never assigned anything to the _tableView instance variable in the -init method, nor did I assign it a value by dragging an outlet somewhere in Interface Builder. To fix that problem, I selected MainWindow.xib (the controller's window) in the Project Navigator(left pane), and then in the middle pane(Interface Builder), I selected the cube representing the File's Owner(selecting the Identity Inspector in the right pane reveals that the File's Owner is the MainWindowController). Then in the right pane, I selected the Connections Inspector, and it revealed an outlet called tableView, which is the IBOutlet variable I declared in MainWindowController.m.
Next, I dragged from the tableView outlet onto the TableView in the middle pane:
Doing that assigns the NSTableView object to the _tableView instance variable that was created by my #property declaration in MyWindowControler.m:
#property (weak) IBOutlet NSTableView* tableView;
As an experiment, I disconnected the outlet, then commented out the #property declaration for tableview, and the tableView outlet no longer appeared in the Connections Inspector. Also, if I change the declaration from:
#property (weak) IBOutlet NSTableView* tableView;
to:
#property (weak) NSTableView* tableView;
...then the tableView outlet doesn't appear in the Connections Inspector. That experiment answered a couple of questions I had about whether I should declare a property as an IBOutlet or not: if you need to assign one of the objects in Interface Builder to one of your variables, then declare the variable as an IBOutlet.
Thereafter, calling [self tableView] reloadData] at the end of -windowDidLoad succeeds in populating the TableView. However, I have not seen any tutorials that call reloadData, and even Apple's guide does not do that.
So, I am still puzzled about whether calling -reloadData is a hack or it's the correct way to do things.
Without it, your table view sits there blissfully clueless about your
expectation that it should even bother asking its datasource for data.
I assumed that an NSTableView automatically queries its datasource when it is ready to display itself, and that my code needed to be able to provide the data at that time.
I don't see you sending -reloadData to your table view anywhere. Tacking it onto the end of -windowDidLoad would be a good place. Without it, your table view sits there blissfully clueless about your expectation that it should even bother asking its datasource for data.
For all it knows, the data is simply not ready / available, so why would it try? More importantly, when should it try? It'd be rather rude of it to try whenever it pleases, considering the UI may not have finished loading / connecting to outlets, or its datasource may be in a vulnerable state (like teardown during/after dealloc) and sending datasource requests may result in a crash, etc.
Two things:
1st, set some breakpoints on when you set your employees array in windowDidLoad vs. when the table first attempts to populate itself and your numberOfRowsInTableView implementation gets called. If the latter happens before the former, then you'll need to add a reloadData after you create your array.
2nd, I personally always use NSCell instead of NSViews for my tables, so I always implement objectValueForTableColumn in my table's datasource. So I'm not sure if there's something different you need to do when you use NSView objects and implement viewForTableColumn. Is there a reason you're not using NSCell?
I have a simple cocoa coredata statusbar application with Xcode 4.6.2.
Here in my AppController.h i have
#interface AppController : NSObject
#property NSStatusItem *statusItem;
#property IBOutlet NSMenu *statusMenu;
In my AppController.m:
#synthesize statusItem = statusItem;
#synthesize statusMenu = statusMenu;
-(void)awakeFromNib{
statusItem = [[NSStatusBar systemStatusBar]statusItemWithLength:NSVariableStatusItemLength];
statusItem.menu = statusMenu;
}
then, in my AppDelegate.m there is a function:
#import "AppController.h"
-(IBAction)someAction:(id)sender{
//code to do something
AppController *x = [[AppController alloc]init];
[x.statusMenu cancelTracking];
}
I want to close the menu via a button that performs an action inside a custom view of a NSMenuItem (from Connection Inspector->Outlets->view ctrl+drag to the button). I cannot select 2 different sent actions for a NSButton, so i have to close the menu declared in AppController class from the IBAction someAction that is in AppDelegate class. How to do it? The code i've posted doesn't work.
Thanks in advance
Your code probably doesn't work because you are initializing a second AppController.
You need a reference to your original AppController in AppDelegate. This can be achieved by using cocoa bindings. In your .XIB file, drag a new blue Object from your Object Library, set it to be a AppController class using the inspector, then control-drag into your AppDelegate header to create a binding. Use that reference and remove the AppController *x = [[AppController alloc] init];.
Maybe try this:
[[NSStatusBar systemStatusBar] removeStatusItem:[GSAppDelegate alloc].statusMenu];
I need to handle that NSFontPanel has been closed. Is there any method which is called, when that happens? Thx for reply.
NSFontPanel is a subclass of NSPanel, which is a subclass of NSWindow. NSWindow has many delegate methods that will inform you of changes in window state.
In your window controller or app delegate, declare conformance to NSWindowDelegate, then obtain the font panel and set its delegate to the controller object. Finally, implement -windowWillClose: in the controller object, and take whatever action you need there.
For example:
/* AppDelegate.h */
#interface AppDelegate : NSObject <NSWindowDelegate>
#property (assign) IBOutlet NSWindow *window;
#end
/* AppDelegate.m */
#implementation AppDelegate
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
NSFontPanel *fp = [[NSFontManager sharedFontManager] fontPanel:YES];
fp.delegate = self;
}
- (void)windowWillClose:(NSNotification *)notification
{
if(notification.object == [[NSFontManager sharedFontManager] fontPanel:NO])
{
/* Handle font panel close here */
NSLog(#"Font panel closing");
}
}
#end
I'm trying to open a window using a NSWindowController in my app delegate.
I created a basic NSWindowController with an associated NIB and try to show the window that way:
#implementation MyAppDelegate
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
// Show the main window from a separate nib
MyWindowController * theWindowController = [[MyWindowController alloc] initWithWindowNibName:#"MyWindowController"];
[theWindowController showWindow:self];
}
#end
When I launch the app, the window of MyWindowController only appears for a fraction of second (seems to be released as soon as it launches).
Using ARC, how could I force the window to stick around and not be flushed right away? I do not use NSDocuments and I want to be able to use many of these MyWindowController concurrently.
You need to add a property to your app delegate (or some other object that's going to stick around for the lifetime of your app) that retains theWindowConroller. For example:
#interface MyAppDelegate : NSObject
#property (strong, nonatomic) MyWindowController * windowController;
#end
Then set this property when you initialize the window controller.
#implementation MyAppDelegate
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
// Show the main window from a separate nib
self.windowController = [[MyWindowController alloc] initWithWindowNibName:#"MyWindowController"];
[theWindowController showWindow:self];
}
#end
Still new to iOS programming, and despite copious amounts of research, I have run in to another roadblock.
What I want to implement:
I want a UITabBarController that gets loaded when I navigate from the main UI. I would also like to use a NIB to define its properties.
All of the examples I can find put the UITabBarController in the AppDelegate, but I would not like to load it unless it gets used. I also dont know if all of the UIGestureRecognizers would remain active if I just did it modally (I cant get a working implementation).
What I have so far
First, I load an initial loading view from AppDelegate
AppDelegate.h
#class InitialViewController;
#interface AppDelegate : UIResponder <UIApplicationDelegate>
#property (strong, nonatomic) UIWindow *window;
#property (strong, nonatomic) UIViewController *viewController;
#end
AppDelegate.m
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
self.viewController = [[InitialViewController alloc] initWithNibName:#"InitialViewController" bundle:nil];
self.window.rootViewController = self.viewController;
[self.window makeKeyAndVisible];
return YES;
}
From this view, as I am just making a skeleton of the UI, I have two buttons, one goes to what would be the main interface, and the other to the UITabBarController.
InitialViewController.h
#interface InitialViewController : UIViewController
- (IBAction)toMain:(id)sender;
- (IBAction)toTabs:(id)sender;
#property (strong, nonatomic) UIViewController *mviewController;
#property (strong, nonatomic) UIViewController *tviewController;
#end
InitialViewController.m
- (IBAction)toMain:(id)sender {
self.mviewController = [[MainViewController alloc] initWithNibName:#"MainViewController" bundle:nil];
[[[UIApplication sharedApplication] delegate] window].rootViewController = self.mviewController;
}
- (IBAction)toTabs:(id)sender {
self.tviewController = [[tabViewController alloc] initWithNibName:#"tabViewController" bundle:nil];
[[[UIApplication sharedApplication] delegate] window].rootViewController = self.tviewController;
}
On loading MainViewController, it behaves exactly like I want. But when I load the tab view, I get one long tab at the bottom and a black background. I can add in things in viewdidload, like changing the background color, but no actual tabs or views linked to the tabs in the XIB.
I suspect there is something I am missing in two areas: in the tab .h, and some linking associated with that in interface builder. Or setting a new rootViewController isnt enough.
tabBarController.h
#import <UIKit/UIKit.h>
#interface iPodViewController : UITabBarController <UITabBarControllerDelegate>
#end
If someone can point me in the right direction and/or show me an implementation that works, I would be most grateful.
-- as a note, when I go in to the tabbar.xib, and use the assistant editor, it opens InitialViewController.h --
Unlike other view controllers (e.g. UITableViewController) you should not subclass the UITabViewController. Therefore, unlike you other view controllers, you don't subclass and then make your subclass the owner of the nib, pointing at the view in the nib, with a customised view.
Instead, for whichever class that you want to own your UITabBarController, add a plain, vanilla UITabBarController as an outlet property on this class. (e.g. your app delegate).
Then create a nib file and drag a UITabBarController object into the nib. Set the owner of the nib to be the class that you want to own your tab bar controller (e.g. your app delegate) and connect the outlet you created as a property to the tab bar controller in the nib.
#interface myTabOwningClass
#property (strong, nonatomic) IBOutlet UITabBarController myTabBarControllerOutlet;
Now at the point you want to create and display your tab bar controller, use the following method:
[[NSBundle mainBundle] loadNibNamed:#"MyTabControllerNib" owner:myTabOwningClass options:nil];
This will initialise the property (i.e. myTabBarControllerOutlet in our example) on the owning class and load the tab bar controller from the nib, including all sub view controllers for each tab etc. that you have defined in the nib.