ipad 点击透明区域取消弹窗

转自：http://stackoverflow.com/questions/2623417/iphone-sdk-dismissing-modal-viewcontrollers-on-ipad-by-clicking-outside-of-it/12454720#12454720

Copy paste this code in your ModalViewController :

    - (void) viewDidAppear:(BOOL)animated
    {
        [super viewDidAppear:animated];
        //Code for dissmissing this viewController by clicking outside it
        UITapGestureRecognizer *recognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleTapBehind:)];
        [recognizer setNumberOfTapsRequired:1];
        recognizer.cancelsTouchesInView = NO; //So the user can still interact with controls in the modal view
        [self.view.window addGestureRecognizer:recognizer];
        
    }
    
    - (void)handleTapBehind:(UITapGestureRecognizer *)sender
    {
        if (sender.state == UIGestureRecognizerStateEnded)
        {
            CGPoint location = [sender locationInView:nil]; //Passing nil gives us coordinates in the window
            
            //Then we convert the tap's location into the local view's coordinate system, and test to see if it's in or outside. If outside, dismiss the view.
            
            if (![self.view pointInside:[self.view convertPoint:location fromView:self.view.window] withEvent:nil])
            {
                // Remove the recognizer first so it's view.window is valid.
                [self.view.window removeGestureRecognizer:sender];
                [self dismissModalViewControllerAnimated:YES];
            }
        }
    }