view的frame高度根据键盘出现、消失改变

- (void)viewDidLoad {

    [super viewDidLoad];

    self.view.backgroundColor = [UIColor yellowColor];

    [[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(action:) name:UIKeyboardWillShowNotification object:nil];

    [[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(action2:) name:UIKeyboardWillHideNotification object:nil];

}

//点击取消键盘

- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{

    [self.textfield resignFirstResponder];

}

//键盘出现

- (void)action:(NSNotification *)notification{

    NSLog(@"%@",notification.userInfo);

    CGRect rect = [notification.userInfo[@"UIKeyboardFrameEndUserInfoKey"]CGRectValue];

    CGRect currentFrame = self.view.frame;

    currentFrame.origin.y -= rect.size.height;

    self.view.frame = currentFrame;

}

//键盘消失

- (void)action2:(NSNotification *)notification{

    NSLog(@"%@",notification.userInfo);

    CGRect rect = [notification.userInfo[@"UIKeyboardFrameBeginUserInfoKey"]CGRectValue];

    CGRect currentFrame = self.view.frame;

    currentFrame.origin.y += rect.size.height;

    self.view.frame = currentFrame;

}