ios - 键盘重叠时向上移动 UITextField

Question

在 ViewA 之上有一个 subview 。请在下面找到屏幕布局。当键盘在选择 UITextField 时显示，即使它不与 UITextField 重叠， View 也会向上滚动。

ViewA
  -> UIButton

subView
  -> UIScrollView
        -> UITextField
        -> UITextField


   ViewA
 -----------
|           |
|           |
|  Button   |
|           |
|           |
 -----------

   subView
 --------------
|              |
|              |
|  UITextField |
|  UITextField |
|              |
 --------------

我已经注册了键盘通知

    - (void) viewWillAppear:(BOOL)animated {

        [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(keyboardDidShow:)
                                                     name:UIKeyboardDidShowNotification
                                                   object:nil];

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


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

            NSDictionary* info = [notification userInfo];
            CGRect kbRect = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue];

            UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, kbRect.size.height, 0.0);
            self.scrollViewIb.contentInset = contentInsets;
            self.scrollViewIb.scrollIndicatorInsets = contentInsets;

            CGRect aRect = self.viewSelf.frame;
            aRect.size.height -= kbRect.size.height;
            CGRect frame = [self.viewSelf convertRect:self.activeField.frame toView:self.viewSelf.superview];
            if (!CGRectContainsPoint(aRect, frame.origin) ) {
                [self.scrollViewIb scrollRectToVisible:self.activeField.frame animated:YES];
            }
    }

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

        self.scrollViewIb.scrollEnabled = true;

        UIEdgeInsets contentInsets = UIEdgeInsetsZero;
        self.scrollViewIb.scrollIndicatorInsets = contentInsets;
        [self.scrollViewIb setContentOffset:CGPointZero animated:false];

}

Answer 1

坐标系转换有一个小错误:convertRect:toView:从接收器的坐标系 转换为传递的 View 的坐标。

如果 self.activeField.frame 如代码所示是 self.scrollViewIb 坐标系中的一个矩形，那么转换应该是这样的...

    CGRect frame = [self.scrollViewIb convertRect:self.activeField.frame toView:self.view];

请注意，我还建议将 self.viewSelf.superview 更改为 self.view。如果此代码在包含所有这些 subview 的 View Controller 中运行，则 self.view 应该足够且正确。