ios - 自动移动 UIScrollView 区域的可见性

Question

如果出现键盘，我想让我的 View 自动向上移动。已经使用苹果的代码here它运作良好。

这就是我管理对象的方式，因此我创建了一个覆盖 UIView 的 UIScrollView。此 UIView 由 UITextField 和 UIButton 组成。

这是我在出现键盘时调整 View 的方式。

#pragma mark - Keyboard Handling

// Call this method somewhere in your view controller setup code.
- (void)registerForKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWasShown:)
                                                 name:UIKeyboardDidShowNotification object:nil];

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

}

// Called when the UIKeyboardDidShowNotification is sent.
- (void)keyboardWasShown:(NSNotification*)aNotification
{
    NSDictionary* info = [aNotification userInfo];
    CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, kbSize.height, 0.0);
    _scrollView.contentInset = contentInsets;
    _scrollView.scrollIndicatorInsets = contentInsets;

    // If active text field is hidden by keyboard, scroll it so it's visible
    // Your app might not need or want this behavior.
    CGRect aRect = self.view.frame;
    aRect.size.height -= kbSize.height;
    if (!CGRectContainsPoint(aRect, _mainView.frame.origin) ) {
        [self.scrollView scrollRectToVisible:_mainView.frame animated:YES];
    }
}

// Called when the UIKeyboardWillHideNotification is sent
- (void)keyboardWillBeHidden:(NSNotification*)aNotification
{
    UIEdgeInsets contentInsets = UIEdgeInsetsZero;
    _scrollView.contentInset = contentInsets;
    _scrollView.scrollIndicatorInsets = contentInsets;
}

但我认为有一点很奇怪。当键盘出现时，它会滚动并且我的 UITextField 变得可见。但我认为它太紧了。

在我看来，如果我的 UITextField 向上移动一点会更好。我的问题是，如何设置它的滚动可见性？看起来应该在这里添加一些变量和一些常量

CGRect aRect = self.view.frame;
aRect.size.height -= kbSize.height;
if (!CGRectContainsPoint(aRect, _mainView.frame.origin) ) {
    [self.scrollView scrollRectToVisible:_mainView.frame animated:YES];
}

注意:我想要的结果

非常感谢，如果有一点提示，我们将不胜感激。

Answer 1

最简单的解决方案是在键盘打开时向上移动 View (或 ScrollView )。

- (void)keyboardWillShow:(NSNotification*)notification{
    [self.view setFrame:CGRectMake(0,-100, self.view.frame.size.width, self.view.frame.size.height)]; // where 100 is the offset
    [self.view setNeedsDisplay];

}

- (void)keyBoardWillHide:(NSNotification*)notification{
    [self.view setFrame:CGRectMake(0,0, self.view.frame.size.width, self.view.frame.size.height)];
    [self.view setNeedsDisplay];
}