I've created a simple subclass of NSView, but calling becomeFirstResponder seems to have no effect - the framework doesn't even call my acceptsFirstResponder method.
However, if I click with my mouse on my view it seems to becomes the first responder and I can receive keyDown events.
Here is my NSView subclass:
#interface MyView : NSView
#end
#implementation MyView
- (void) keyDown: (NSEvent*) with {
NSLog(#"keyDown");
}
- (BOOL)acceptsFirstResponder {
NSLog(#"acceptsFirstResponder");
return YES;
}
- (BOOL)canBecomeKeyView {
NSLog(#"canBecomeKeyView");
return YES;
}
#end
And here is how I'm setting it up in my AppDelegate:
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification {
NSRect frameRect = NSMakeRect(0,0,100,100);
MyView *myView = [[MyView alloc] initWithFrame:frameRect];
[_window.contentView addSubview:myView];
[myView becomeFirstResponder];
}
What am I doing wrong?
Whoops - the documentation says 'Never invoke this method directly'. So I should call
[_window makeFirstResponder:myView];
instead of
[myView becomeFirstResponder];
Thanks to Willeke for the hint.
Related
In my code, when I set canDisplayBannerAds=YES on my view controller, I get callbacks to viewDidLayoutSubviews when the ad disappears but not when the ad appears. I'm guessing this is because Apple moves the original self.view of the view controller to self.originalContentView when you set canDisplayBannerAds to YES.
My question is, what is a reasonable work around for this?
My solution to this problem is to replace self.view before setting canDisplayBannerAds=YES with a UIView that overrides layoutSubviews.
#protocol LayoutViewDelegate <NSObject>
- (void) layout;
#end
#interface LayoutView : UIView
#property (nonatomic, weak) id<LayoutViewDelegate> delegate;
#end
#implementation LayoutView
- (void) layoutSubviews {
[super layoutSubviews];
if (self.delegate) [self.delegate layout];
}
#end
I do this replacement in viewDidLoad:
- (void)viewDidLoad
{
[super viewDidLoad];
NSLog(#"Calendar.viewDidLoad");
// Replace the view, before setting up ads for iOS7, so we can get callbacks for viewDidLayoutSubviews; otherwise, we only get viewDidLayoutSubviews callbacks when ad disappears.
if ([Utilities ios7OrLater]) {
self.layoutView = [[LayoutView alloc] initWithFrame:self.view.frame];
self.view = self.layoutView;
self.layoutView.delegate = self;
}
}
And in viewDidAppear, I do:
- (void) viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
if ([Utilities ios7OrLater]) {
self.canDisplayBannerAds = YES;
}
}
And I add the delegate method:
// This *always* gets called when the banner ad appears or disappears.
#pragma - LayoutViewDelegate method
- (void) layout {
// do useful stuff here
}
#pragma -
I am having some troubles understanding how to wire a custom NSView for an NSMenuItem to support both animation and dragging and dropping. I have the following subclass of NSView handling the bulk of the job. It draws my icon when the application launches correctly, but I have been unable to correctly setup the subview to change when I invoke the setIcon function from another caller. Is there some element of the design that I am missing?
TrayIconView.m
#import "TrayIconView.h"
#implementation TrayIconView
#synthesize statusItem;
static NSImageView *_imageView;
- (id)initWithFrame:(NSRect)frame
{
self = [super initWithFrame:frame];
if (self) {
statusItem = nil;
isMenuVisible = NO;
_imageView = [[NSImageView alloc] initWithFrame:[self bounds]];
[self addSubview:_imageView];
}
return self;
}
- (void)drawRect:(NSRect)dirtyRect
{
// Draw status bar background, highlighted if menu is showing
[statusItem drawStatusBarBackgroundInRect:[self bounds]
withHighlight:isMenuVisible];
}
- (void)mouseDown:(NSEvent *)event {
[[self menu] setDelegate:self];
[statusItem popUpStatusItemMenu:[self menu]];
[self setNeedsDisplay:YES];
}
- (void)rightMouseDown:(NSEvent *)event {
// Treat right-click just like left-click
[self mouseDown:event];
}
- (void)menuWillOpen:(NSMenu *)menu {
isMenuVisible = YES;
[self setNeedsDisplay:YES];
}
- (void)menuDidClose:(NSMenu *)menu {
isMenuVisible = NO;
[menu setDelegate:nil];
[self setNeedsDisplay:YES];
}
- (void)setIcon:(NSImage *)icon {
[_imageView setImage:icon];
}
TrayIconView.h
#import <Cocoa/Cocoa.h>
#interface TrayIconView : NSView
{
BOOL isMenuVisible;
}
#property (retain, nonatomic) NSStatusItem *statusItem;
- (void)setIcon:(NSImage *)icon;
#end
The solution to this problem was actually outside of the view detailed here. The caller of the interface was being double instantiated on accident, thus nulling out the reference to the previously created NSView. After correcting that concern the app draws and works just fine.
With regard to dragging, I just implemented a subclass of NSView that implemented the Cocoa draggable protocol and added it as a subview to this parent class. That allows dragging onto the currently established NSRect that contains the menubar icon.
How do I get a reference to the UIViewController of a touched view?
I am using a UIPanGestureRecognizer on the view of a UIViewController. Here's how I initialize it:
TaskUIViewController *thisTaskController = [[TaskUIViewController alloc]init];
[[self view]addSubview:[thisTaskController view]];
UIPanGestureRecognizer *panRec = [[UIPanGestureRecognizer alloc]initWithTarget:self action:#selector(handlePan:)];
[[thisTaskController view] addGestureRecognizer:panRec];
In the tiggered action triggered using the gesture recognizer I am able to get the view from the parameter using recognizer.view
- (IBAction)handlePan:(UIPanGestureRecognizer *)recognizer {
UIView *touchedView = [[UIView alloc]init];
touchedView = (UIView*)[recognizer view];
...
}
However what I really need is the underlying UIViewController of the view touched. How can I get a reference to the UIViewController that contains this view instead of only the UIView?
I would say that it is more a design issue than just getting a reference. So I would follow several simple advises:
Owner should catch events from its view. I.e. TaskUIViewController sould be a target to UIPanGestureRecognizer which you added to its view.
If a controller has a sub-controller and waits from its sub-controller some responses - implement this as delegate.
You have memory leak in your "handlePan:" method.
Here is a skeleton to solve your issue:
#protocol CallbackFromMySubcontroller <NSObject>
- (void)calbackFromTaskUIViewControllerOnPanGesture:(UIViewController*)fromController;
#end
#interface OwnerController : UIViewController <CallbackFromMySubcontroller>
#end
#implementation OwnerController
- (id)init
{
...
TaskUIViewController *thisTaskController = [[TaskUIViewController alloc] init];
...
}
- (void)viewDidLoad
{
...
[self.view addSubview:thisTaskController.view];
...
}
- (void)calbackFromTaskUIViewControllerOnPanGesture:(UIViewController*)fromController
{
NSLog(#"Yahoo. I got an event from my subController's view");
}
#end
#interface TaskUIViewController : UIViewController {
id <CallbackFromMySubcontroller> delegate;
}
#end
#implementation TaskUIViewController
- (id)initWithOwner:(id<CallbackFromMySubcontroller>)owner
{
...
delegate = owner;
...
}
- (void)viewDidLoad
{
UIPanGestureRecognizer *panRec = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(handlePan:)];
[self.view addGestureRecognizer:panRec];
[panRec release];
}
- (void)handlePan:(UIPanGestureRecognizer *)recognizer {
...
[delegate calbackFromTaskUIViewControllerOnPanGesture:self];
...
}
#end
[touchedView nextResponder] will return the UIViewController object that manages touchedView (if it has one) or touchedView's superview (if it doesn’t have a UIViewController object that manages it).
For more information, see the UIResponder Class Reference. (UIViewController and UIView are subclasses of UIResponder.)
In your case, since you happen to know that touchedView is your viewController's view (and not, for instance, a subview of your viewController's view), you can just use:
TaskUIViewController *touchedController = (TaskUIViewController *)[touchedView nextResponder];
In the more general case, you could work up the responder chain until you find an object of kind UIViewController:
id aNextResponder = [touchedView nextResponder];
while (aNextResponder != nil)
{
if ([aNextResponder isKindOfClass:[UIViewController class]])
{
// we have found the viewController that manages touchedView,
// so we break out of the while loop:
break;
}
else
{
// we have yet to find the managing viewController,
// so we examine the next responder in the responder chain
aNextResponder = [aNextResponder nextResponder];
}
}
// outside the while loop. at this point aNextResponder points to
// touchedView's managing viewController (or nil if it doesn't have one).
UIViewController *eureka = (UIViewController *)aNextResponder;
I have a ViewController in which I create a Modal ViewController. I have a SEL value in my modal that I set when it is being instantiated from the parent.
setDateViewController.selectorName = #selector(myMethod:);
In my modal I am trying to call this SEL like:
[[self parentViewController] performSelector:self.selectorName withObject:selectedDate afterDelay:.5];
{selectedDate} is obviously a value from my modal.
I don't get any errors or stack, however, this SEL (method) on my parent is never being called. For some reason I think this should work, but something tells me I'm way off track.
Thanks.
I guess [self parentviewcontroller] is not returning anything.
Try UiviewController* v = [self parentviewcontroller]; and check if is nil. Most probably it should be nil. Else if its was pointing to another object of different class then it would have crashed. Please do one thing. YOu should set bot the object and the methd you need to call. IT will solve any issues if it has any.
setDateViewController.selectorDelegate = self;
setDateViewController.selectorName = #selector(myMethod:);
call like this from parent class. So you can dynamically specify the method and the object you want to call gives more flexibility.
and use,
[selectorDelegate performSelector:self.selectorName withObject:selectedDate afterDelay:.5];
this should solve any issues.
Perhaps you would consider added a delegate protocol to your modal that will allow it to call the method on the parent.
Quick (untested) example:
// MyController.h
#protocol MyControllerDelegate;
#interface MyController : UIViewController
{
id<MyControllerDelegate> delegate;
}
#end
#protocol MyControllerDelegate <NSObject>
- (void)methodToCall:(id)sender;
#end
// MyControler.m
#implementation MyController
- (void) loadView
{
[super loadView];
UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];
btn.frame = CGRectMake(20.0f, 20.0f, 50.0f, 30.0f);
[btn setTitle:#"blah" forState:UIControlStateNormal];
[btn addTarget:self.delegate
action:#selector(methodToCall:)
forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:btn];
}
#end
// ParentController.h
#interface ParentController : UIViewController<MyControllerDelegate>
{
}
#end
// ParentController.m
#implementation ParentController
- (void)methodToCall:(id)sender
{
NSLog(#"HERE");
}
#end
Just make sure when you are creating your modal controller you set it's delegate to self on the parent:
MyController *controller = [[MyController alloc] init];
controller.delegate = self;
[self presentModalViewController:controller animated:YES];
I have a UINavigationController and I would like the view of every view controller that is popped onto the stack to have a common padding/margin (e.g. 25 pixels on all sides). What is the best way to accomplish this?
I originally thought that I could implement UINavigationControllerDelegate and inside the navigationController:didShowViewController:animated or navigationController:willShowViewController:animated methods, simply change the frame of the view controller that was about to be displayed. This does not seem to have an effect though.
I tried to do the same thing inside the view controller's viewDidAppear and viewWillAppear methods, but this also did not work. Ideally, I don't want to put any logic in the controllers anyway, as they may not always be used inside a navigation controller.
One last idea that I haven't tried yet is to create a "wrapper" UIViewController that would actually get pushed onto this stack. This wrapper would add the real view controller's view as a subview with a frame that would provide the desired margin. The downside here is that I would need to subclass UINavigationController and override pushViewController:animated, where the wrapper would be initialized and pushed. Apple's documentation indicates that UINavigationController is not meant to be subclassed.
Thanks in advance.
I solved this by putting a "wrapper" UIView around the UIViewController's view instead of the UIViewController itself. The wrapper view then pads the subview by setting the subview's frame in the layoutSubviews method.
I've attached the code I used for convenience. To use, replace your UINavigationController with the PaddedNavigationController, and set the PaddedNavigationController's insets property.
PaddedNavigationController.h:
#import <Foundation/Foundation.h>
#interface PaddedNavigationController : UINavigationController
{
UIEdgeInsets _insets;
}
#property (nonatomic, assign) UIEdgeInsets insets;
#end
PaddedNavigationController.m:
#import "PaddedNavigationController.h"
#interface PaddedView : UIView
{
UIView *_view;
UIEdgeInsets _insets;
}
#property (nonatomic, assign) UIEdgeInsets insets;
+ (PaddedView *) wrapView:(UIView *)view withInsets:(UIEdgeInsets)insets;
- (id) initWithView:(UIView *)view insets:(UIEdgeInsets)insets;
#end
#implementation PaddedNavigationController
#synthesize insets = _insets;
- (void) pushViewController:(UIViewController *)viewController animated:(BOOL)animated
{
//check if the UIViewController's view has already been wrapped by the PaddedView; don't want to wrap it twice
if(![viewController.view isKindOfClass:[PaddedView class]])
{
viewController.view = [PaddedView wrapView:viewController.view withInsets:self.insets];
}
[super pushViewController:viewController animated:animated];
}
- (void) setInsets:(UIEdgeInsets)insets
{
_insets = insets;
//loop through this navigation controller's view controllers and set the new insets on any PaddedViews
for(UIViewController *viewController in self.viewControllers)
{
if([viewController.view isKindOfClass:[PaddedView class]])
{
PaddedView *padded = (PaddedView *)viewController.view;
padded.insets = insets;
}
}
}
#end
#implementation PaddedView
#synthesize insets = _insets;
+ (PaddedView *) wrapView:(UIView *)view withInsets:(UIEdgeInsets)insets
{
return [[[PaddedView alloc] initWithView:view insets:insets] autorelease];
}
- (id) initWithView:(UIView *)view insets:(UIEdgeInsets)insets
{
if(self = [super initWithFrame:view.frame])
{
_insets = insets;
self.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
_view = [view retain];
[self addSubview:view];
}
return self;
}
- (void) dealloc
{
[_view release];
[super dealloc];
}
- (void) layoutSubviews
{
//apply the insets to the subview
_view.frame = CGRectMake(self.insets.left, self.insets.top, self.frame.size.width - self.insets.left - self.insets.right, self.frame.size.height - self.insets.top - self.insets.bottom);
}
- (void) setInsets:(UIEdgeInsets)insets
{
_insets = insets;
//we need to re-layout the subviews as the insets have changed
[self layoutSubviews];
}
#end