ios - 隐藏键盘时Blackview来了

Question

这是我为在用户开始在 TextView 中输入时移动 TextView 而编写的一些代码。

这是代码，

-(BOOL)textViewShouldBeginEditing:(UITextView *)textView{
    if(textView == _textViewMsg || textView == _subjectView ){
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardDidShow:) name:UIKeyboardDidShowNotification object:nil];
   // return YES;
    }
    return YES;
}

- (BOOL)textViewShouldEndEditing:(UITextView *)textView{
    if(textView == _textViewMsg || textView == _subjectView ){
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardDidHide:) name:UIKeyboardDidHideNotification object:nil];

    [self.view endEditing:YES];
    }
    return YES;
}


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

    [self.view setFrame:CGRectMake(0,-50,320,460)];
}

-(void)keyboardDidHide:(NSNotification *)notification
{
    [self.view setFrame:CGRectMake(0,60,320,520)];
}

当我在移动中单击 TextView (在主题中) View 时，我可以在 TextView 中键入内容。它工作正常。 (图 1)

当我点击完成按钮时，同时隐藏，即在键盘隐藏时，一个黑色 View 出现(检查图像 2)几秒钟，然后再次出现正常 View 。

编辑:

解决方案:@michael 刚刚给我解决方案

将 UIKeyboardDidHideNotification 更改为 UIKeyboardWillHideNotification 它对我有用。

出现新问题: 当我开始输入前 2 个 TextView 时，即请求者、名字和姓氏......我无法输入它，因为它正在向上移动。

Answer 1

这是因为当系统动画完成时，您在键盘消失后更改了 View 的框架。快速修复:将 UIKeyboardDidHideNotification 更改为 UIKeyboardWillHideNotification

但如果您不介意的话，我想指出您代码中的其他几个项目。

1: 每次用户开始编辑时，您都在订阅通知。这意味着当用户第二次开始输入时，您的代码将被触发两次。在 viewDidAppear 上订阅通知和在 viewWillDisappear 上取消订阅更合适:

- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear: animated];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardDidShow:) name:UIKeyboardDidShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardDidHideNotification object:nil];
}

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];
    [[NSNotificationCenter defaultCenter] removeObserver:self];
}

2: 然后您将框架更改为恒定值。但现在苹果支持不同尺寸的不同键盘，更不用说键盘尺寸在不同设备和不同可能模式下有所不同。因此，从通知中获取键盘的大小更为明智:

- (void)keyboardDidShow:(NSNotification *)aNotification
{
    CGRect keyboardFrame = [[aNotification.userInfo valueForKey: UIKeyboardFrameEndUserInfoKey] CGRectValue];
    CGRect overlap =  CGRectIntersection( self.view.frame, keyboardFrame);
    // Setup new frmae according to overlap, for example reduce size by half of overlap, and move up by another half
    CGRect newFrame = self.view.frame;
    newFrame.origin.y -= overlap.size.height / 2.0
    newFrame.size.height -= overlap.size.height / 2.0
    self.view.frame = newFrame;
}

3: 动画:您也可以从通知中获取键盘动画持续时间: UIKeyboardAnimationDurationUserInfoKey:

NSTimeInterval duration = [[aNotification.userInfo  valueForKey: UIKeyboardAnimationDurationUserInfoKey] doubleValue];
[UIView animateWithDuration:duration animations:^{
    self.view.frame = newFrame;
}];

4 由于您似乎在使用 ScrollView (UITableView 和 UICollectioView 是 ScrollView )，因此您可以不更改框架，而是更改内容插入(向底部 ScrollView 添加空白区域)

[self.view setContentInset:UIEdgeInsetsMake(0, 0, overlap.size.height, 0)];

5 考虑使用自动布局。