Objective C: Detecting a shake

问题

I'm using the shake api like this:

- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event 
{
    if (event.subtype == UIEventSubtypeMotionShake)
    {
        [img stopAnimating];    
    }
}

How do I detect that the shaking has stopped?

回答1:

You are on the right track, however, there are still more things you need to add to detect shaking:

You can test this by adding an NSLog to the motionBegan or motionEnded methods, and in the Simulator, press CONTROL + COMMAND + Z

#pragma mark - Shake Functions

-(BOOL)canBecomeFirstResponder {
    return YES;
}

-(void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:NO];
    [self becomeFirstResponder];
}

-(void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:NO];
}

-(void)viewDidDisappear:(BOOL)animated {
    [self resignFirstResponder];
    [super viewDidDisappear:NO];
}

-(void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event
{
    if (motion == UIEventSubtypeMotionShake )
    {
        // shaking has began.   
    }   
}


-(void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event
{
    if (motion == UIEventSubtypeMotionShake )
    {
        // shaking has ended
    }
}

来源：https://stackoverflow.com/questions/4807551/objective-c-detecting-a-shake