Iphone SDK通过点击它外面的ipad上关闭Modal ViewControllers

让你的模态视图控制器附加一个手势识别器到视图的窗口：

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];
[recognizer release];

处理代码：

- (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];
        }
     }
}

就是这样。 HIG被诅，，这是一个有用的和经常直观的行为。