用来处理 uitextview 编辑时,键盘挡住输入框的, 这个会将整个frame 上移

ios

// 注意,如果输入的是汉字的话,输入拼音后,会出现新的一行,让你选择拼音所对应的汉字,这个也会触发UIKeyboardWillShowNotification
// 所以,你要加个变量,来判断键盘是否消失,没消失的话就不在上移界面


- (void)viewDidLoad
{
    [super viewDidLoad];
	// Do any additional setup after loading the view.
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillShow:)
                                                 name:UIKeyboardWillShowNotification
                                               object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillHide:)
                                                 name:UIKeyboardWillHideNotification
                                               object:nil];
}

#pragma mark keyboard show hide

- (UIView *)findViewThatIsFirstResponder
{
    if (self.view.isFirstResponder) {
        return self.view;
    }
    
    for (UIView *subView in self.view.subviews) {
        if ([subView isFirstResponder]) {
            return subView;
        }
    }
    
    return nil;
}

- (void)keyboardWillShow:(NSNotification *)aNotification
{
    if (!self.wasKeyboardDidShow) {
        NSTimeInterval animationDuration =
        [[[aNotification userInfo] objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
        CGRect frame = self.view.frame;
//        frame.origin.y -= 160;
        UIView *respView = [self findViewThatIsFirstResponder];
        if (respView.frame.origin.y + respView.frame.size.height > frame.size.height-160) {
            frame.origin.y -= respView.frame.origin.y + respView.frame.size.height - frame.size.height + 180;
        }
        [UIView beginAnimations:@"ResizeForKeyboard" context:nil];
        [UIView setAnimationDuration:animationDuration];
        self.view.frame = frame;
        [UIView commitAnimations];
        self.wasKeyboardDidShow = YES;
    }
}

- (void)keyboardWillHide:(NSNotification *)aNotification
{
    NSTimeInterval animationDuration =
    [[[aNotification userInfo] objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
    CGRect frame = self.view.frame;
    frame.origin.y = 0;
    [UIView beginAnimations:@"ResizeForKeyboard" context:nil];
    [UIView setAnimationDuration:animationDuration];
    self.view.frame = frame;
    [UIView commitAnimations];
    self.wasKeyboardDidShow = NO;
}