编辑时无法正常工作时滚动视图

Question

我想在用户开始编辑UITextField并且文本字段被键盘隐藏时进行UIScrollView滚动。我正在使用来自以下线程的示例。

How to make a UITextField move up when keyboard is present

我有我的四个视UITextFields。当第一次显示键盘时，视图不会自动滚动。如果我用显示的键盘单击另一个文本字段，则UIScrollView按照预期滚动。 隐藏键盘（通过点击“完成”按钮）并再次轻敲UITextField会出现同样的问题：UIScrollView首先不滚动，但当焦点转换到另一个文本字段时，它完全滚动。

任何人都可以帮我吗？

在viewDidLoad我设置的滚动视图

keyboardIsShown = NO; 
CGSize scrollContentSize = CGSizeMake(320, 350); 
self.scrollView.contentSize = scrollContentSize; 

我为键盘通知登录尺寸在viewWillAppear

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:self.view.window]; 
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:self.view.window]; 

然后我注销在viewWillDisappear

[[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil]; 
[[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil]; 

下面的两个方法由通知调用离子。

- (void)keyboardWillShow:(NSNotification *)n { 
    if (keyboardIsShown) { 
     return; 
    } 

    NSDictionary *userInfo = [n userInfo]; 

    NSValue *boundsValue = [userInfo objectForKey:UIKeyboardFrameBeginUserInfoKey]; 
    CGSize keyboardSize = [boundsValue CGRectValue].size; 

    CGRect viewFrame = self.scrollView.frame; 
    viewFrame.size.height -= (keyboardSize.height - 50); 

    [UIView beginAnimations:nil context:NULL]; 
    [UIView setAnimationBeginsFromCurrentState:YES]; 

    [UIView setAnimationDuration:0.3]; 
    [self.scrollView setFrame:viewFrame]; 
    [UIView commitAnimations]; 

    keyboardIsShown = YES; 
} 

- (void)keyboardWillHide:(NSNotification *)n { 
    NSDictionary *userInfo = [n userInfo]; 

    NSValue *boundsValue = [userInfo objectForKey:UIKeyboardFrameEndUserInfoKey]; 
    CGSize keyboardSize = [boundsValue CGRectValue].size; 

    CGRect viewFrame = self.scrollView.frame; 
    viewFrame.size.height += (keyboardSize.height - 50); 

    [UIView beginAnimations:nil context:NULL]; 
    [UIView setAnimationBeginsFromCurrentState:YES]; 

    [UIView setAnimationDuration:0.3]; 
    [self.scrollView setFrame:viewFrame]; 
    [UIView commitAnimations]; 

    keyboardIsShown = NO; 
} 

Answer 1

如果您想在键盘可见时显示textfeild，请使用下面的代码。不要跟随滚动视图。如果强制使用scrollView，则忽略此答案。

#define kOFFSET_FOR_KEYBOARD 280.0 

- (void)keyboardWillHide:(NSNotification *)notif { 
    [self setViewMoveUp:NO]; 
} 


- (void)keyboardWillShow:(NSNotification *)notif{ 
    [self setViewMoveUp:YES]; 
} 


- (void)textFieldDidBeginEditing:(UITextField *)textField { 
    stayup = YES; 
    [self setViewMoveUp:YES]; 
} 


- (void)textFieldDidEndEditing:(UITextField *)textField { 
    stayup = NO; 
    [self setViewMoveUp:NO]; 
} 

//method to move the view up/down whenever the keyboard is shown/dismissed 
-(void)setViewMoveUp:(BOOL)moveUp 
{ 
    [UIView beginAnimations:nil context:NULL]; 
    [UIView setAnimationDuration:0.3]; // if you want to slide up the view 
    [UIView setAnimationBeginsFromCurrentState:YES]; 

    CGRect rect = self.view.frame; 
    if (moveUp) 
    { 
     // 1. move the view's origin up so that the text field that will be hidden come above the keyboard 
     // 2. increase the size of the view so that the area behind the keyboard is covered up. 

     if (rect.origin.y == 0) { 
      rect.origin.y -= kOFFSET_FOR_KEYBOARD; 
      //rect.size.height += kOFFSET_FOR_KEYBOARD; 
     } 

    } 
    else 
    { 
     if (stayup == NO) { 
      rect.origin.y += kOFFSET_FOR_KEYBOARD; 
      //rect.size.height -= kOFFSET_FOR_KEYBOARD; 
     } 
    } 
    self.view.frame = rect; 
    [UIView commitAnimations]; 
} 

试试这种方法。根据您的要求编辑它。