iOS获取键盘的高度

利用观察者 来监听是否弹出键盘

//监听弹出键盘

[[NSNotificationCenter defaultCenter] addObserver:self

selector:@selector(keyboardWillShow:)

name:UIKeyboardWillShowNotification

object:nil];

//可以监听收回键盘

[[NSNotificationCenter defaultCenter] addObserver:self

selector:@selector(keyboardWillHide:)

name:UIKeyboardWillHideNotification

object:nil];

//创建观察者回调方法

- (void)keyboardWillShow:(NSNotification *)aNotification

{

    //创建自带来获取穿过来的对象的info配置信息

    NSDictionary *userInfo = [aNotification userInfo];

    //创建value来获取 userinfo里的键盘frame大小

    NSValue *aValue = [userInfo         objectForKey:UIKeyboardFrameEndUserInfoKey];

    //创建cgrect 来获取键盘的值

    CGRect keyboardRect = [aValue CGRectValue];

    //最后获取高度 宽度也是同理可以获取

    int height = keyboardRect.size.height;

    CGRect rect = self.view.frame;

    rect.orignal.y = - height;

    self.view.frame = rect;

}

- (void)keyboardWillHide:(NSNotification *)aNotification

{
    CGRect rect = self.view.frame;

    rect.orignal.y = - height;

    self.view.frame = rect;
}