笔记--键盘的显示和隐藏

在viewController里:

// 注册键盘事件监听器，键盘消失和键盘显示

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWasShown:) name:UIKeyboardDidShowNotification object:nil];

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillBeHidden:) name:UIKeyboardWillHideNotification object:nil];

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

    // 键盘显示的同时,将界面上移一段距离

    [UIView beginAnimations:nil context:NULL];

    [UIView setAnimationDuration:0.3];

    CGRect aRect = self.view.frame;

    aRect.size.height -= 40;//可以自定义

    self.view.frame = aRect;

    [UIView commitAnimations];

}

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

   //键盘隐藏时,将界面恢复过来

    [UIView beginAnimations:nil context:NULL];

    [UIView setAnimationDuration:0.3];

    CGRect aRect = self.view.frame;

    aRect.size.height += 40;

    self.view.frame = aRect;

    [UIView commitAnimations];

}