iPhone开发 当输入的键盘会挡住UITextField的处理事件

//添加键盘的监听事件

[[NSNotificationCenterdefaultCenter] addObserver:selfselector:@selector(keyboardWasShown:) name:UIKeyboardDidShowNotificationobject:nil];

#pragma mark 滚动scrollview 使被隐藏的textfield显示在屏幕正确的位置（软键盘的上方）

- (void)keyboardWasShown:(NSNotification*)aNotification {

NSDictionary* info = [aNotification userInfo];

    //键盘的大小

    CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    CGRect aRect = self.view.frame;

    aRect.size.height -= kbSize.height;

// 输入项区域被认为定高

CGPoint activeFieldRect = activeText.frame.origin;

    int actHeight=activeFieldRect.y;

    int actSelfHeight=activeText.frame.size.height;

if(aRect.size.height-actHeight-actSelfHeight<0)

    {

        CGPoint scrollPoint = CGPointMake(0.0, -(aRect.size.height-actSelfHeight-actHeight));

        [scView setContentOffset:scrollPoint animated:YES];

    }

}