motionEnded not being called (no view controller)

Question

I think I've done all I should to detect a shake, but motionEnded:withEvent: never gets called. (One wrinkle is that I don't have a UIViewController - my app is based on the "OpenGL ES App" template.)

I've added application.applicationSupportsShakeToEdit = YES; to my application:didFinishLaunchingWithOptions:, and

- (BOOL)canBecomeFirstResponder { return YES; }

to EAGLView.m (which does get called), and [self becomeFirstResponder]; to initWithCoder: (and have tried various other places too).

But the debugger never hits

- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event

Am I missing some step? Do I have to have a controller?

(I'm using iOS 3.2 in the iPad simulator.)

score 4 · Answer 1 · answered Sep 20 '13 at 19:12

4

You must add this to your controller:

-(void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];
    [self becomeFirstResponder];
}

-(BOOL)becomeFirstResponder
{
    return YES;
}

answered Sep 20 '13 at 19:12

exeapps

119
1
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This is correct way to do it. It worked for me. I had a problem because my view was in navigation view controller – Markicevic May 09 '17 at 11:31
this somehow messes up the repsonder chain for IBActions – Hogdotmac Dec 17 '18 at 13:31

score 3 · Answer 2 · edited Aug 29 '15 at 09:22

The way the UIResponder chain works with the shake notification is obnoxious. Seems that UIWindow always gets the notification, and then sub-responders may or may not depending on whats above them in the chain. I created a UIWindow subclass, and defined it as my window class with the following:

- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event 
{
    if (event.type == UIEventSubtypeMotionShake) 
        [[NSNotificationCenter defaultCenter] postNotificationName:@"UIEventSubtypeMotionShakeEnded" object:nil];
}

Then, for any views that wanted the shake notifications, I simply had them add themselves as an observer to the UIEventSubtypeMotionShakeEnded event, and they got it every time.

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(shakeNotification:)
                                             name:@"UIEventSubtypeMotionShakeEnded" object:nil];

a more indepth answer would be on http://stackoverflow.com/questions/150446/how-do-i-detect-when-someone-shakes-an-iphone by Joe D'Andrea — LolaRun, Jun 08 '11 at 07:45
Did you notice you verified `event.type` against `UIEventSubtypeMotionShake` which is a subtype? By coincidence this worked because `UIEventSubtypeMotionShake` and `UIEventTypeMotion` have the same value. — bio, Dec 14 '15 at 15:02

score 0 · Answer 3 · answered Aug 21 '10 at 00:12

0

You can't become the first responder before your view is in the view hierarchy.

answered Aug 21 '10 at 00:12

tc.

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I tried calling it other places too but it didn't seem to help - like in `drawView`. – Grumdrig Aug 21 '10 at 20:28
Can you create a view controller to stick the EAGLView in, and call becomeFirstResponder in viewDidAppear:? – tc. Aug 23 '10 at 01:56
I was sorta trying to avoid that if I can. `UIView`s are `UIResponder`s, if I'm not mistaken. – Grumdrig Aug 24 '10 at 18:09

score 0 · Accepted Answer · answered Aug 24 '10 at 21:40

0

Updating to the latest version of the SDK magically fixed the problem. [Shrug]

answered Aug 24 '10 at 21:40

Grumdrig

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motionEnded not being called (no view controller)

4 Answers4