获取键盘高度

• (void)viewDidLoad {
  [super viewDidLoad];
  //增加监听，当键盘出现或改变时收出消息
  [[NSNotificationCenter defaultCenter] addObserver:self
  selector:@selector(keyboardWillShow:)
  name:UIKeyboardWillShowNotification
  object:nil];
  }
  //当键盘出现或改变时调用
• (void)keyboardWillShow:(NSNotification *)aNotification
  {
  //获取键盘的高度
  NSDictionary *userInfo = [aNotification userInfo];
  NSValue *aValue = [userInfo objectForKey:UIKeyboardFrameEndUserInfoKey];
  CGRect keyboardRect = [aValue CGRectValue];
  self.keyboardHeight = keyboardRect.size.height;
  NSLog(@”%d”,self.keyboardHeight);
  }