ios - 如何根据键盘管理 ScrollView (向上和向下)在 Objective-C 中使用 NSNotificationCenter 在屏幕中显示和隐藏

Question

考虑我有一个屏幕，在这个屏幕上我有 10 个文本字段，现在我的问题是当键盘打开时键盘在我的 3 个文本字段上。那么我如何使用 UIScrollView 和 NSNotification Center 来管理它呢？

Answer 1

是的，我有一个代码，我相信它绝对适合你。

 [[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);
   MyScrollView.contentInset = contentInsets;
   MyScrollView.scrollIndicatorInsets = contentInsets;
 }

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