使用iOS SDK:

我有一个带UITextFields的UIView,可以启动键盘。我需要它能够:

启动键盘后,允许滚动UIScrollView的内容以查看其他文本字段自动“跳转”(通过向上滚动)或缩短

我知道我需要一个UIScrollView。我已经尝试将UIView的类更改为UIScrollView,但仍然无法上下滚动文本框。

我需要UIView和UIScrollView吗?一个在另一个里面吗?

要自动滚动到活动文本字段,需要执行哪些操作?

理想情况下,尽可能多的组件设置将在Interface Builder中完成。我只想编写需要的代码。

注意:我使用的UIView(或UIScrollView)是由一个选项卡(UITabBar)启动的,它需要正常工作。


我正在添加滚动条,只为键盘出现时使用。尽管不需要它,但我觉得它提供了一个更好的界面,例如,用户可以滚动和更改文本框。

当键盘上下移动时,我可以改变UIScrollView的框架大小。我只是在使用:

-(void)textFieldDidBeginEditing:(UITextField *)textField {
    //Keyboard becomes visible
    scrollView.frame = CGRectMake(scrollView.frame.origin.x,
                                  scrollView.frame.origin.y,
    scrollView.frame.size.width,
    scrollView.frame.size.height - 215 + 50);   // Resize
}

-(void)textFieldDidEndEditing:(UITextField *)textField {
    // Keyboard will hide
    scrollView.frame = CGRectMake(scrollView.frame.origin.x,
                                  scrollView.frame.origin.y,
                                  scrollView.frame.size.width,
                                  scrollView.frame.size.height + 215 - 50); // Resize
}

然而,这不会自动“向上移动”或将可见区域中的下部文本字段居中,这是我真正想要的。


当前回答

试试这个小把戏。

- (void)textFieldDidBeginEditing:(UITextField *)textField
{
    [self animateTextField: textField up: YES];
}

- (void)textFieldDidEndEditing:(UITextField *)textField
{
    [self animateTextField: textField up: NO];
}

- (void) animateTextField: (UITextField*) textField up: (BOOL) up
{
    const int movementDistance = textField.frame.origin.y / 2; // tweak as needed
    const float movementDuration = 0.3f; // tweak as needed

    int movement = (up ? -movementDistance : movementDistance);

    [UIView beginAnimations: @"anim" context: nil];
    [UIView setAnimationBeginsFromCurrentState: YES];
    [UIView setAnimationDuration: movementDuration];
    self.view.frame = CGRectOffset(self.view.frame, 0, movement);
    [UIView commitAnimations];
}

其他回答

非常轻量级的解决方案可以使用KeyboardAnimator。

项目获得了示例实现,文档编制仍在进行中。。。

适当用法:它具有UITextField和UITextView的特定实现

限制::它完全基于objective-c,swift版本将很快推出。

这对我有用:

func setupKeyboardNotifications() {
    NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWasShown:"), name: UIKeyboardDidShowNotification, object: nil)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillBeHidden:"), name: UIKeyboardWillHideNotification, object: nil)
}

func keyboardWasShown(aNotification:NSNotification) {
    let info = aNotification.userInfo
    let infoNSValue = info![UIKeyboardFrameBeginUserInfoKey] as NSValue
    let kbSize = infoNSValue.CGRectValue().size
    UIView.beginAnimations(nil, context: nil)
    UIView.setAnimationDuration(0.3)
    var rect : CGRect = self.view.frame
    rect.size.height -= kbSize.height

    self.view.frame = rect
    UIView.commitAnimations()
}

func keyboardWillBeHidden(aNotification:NSNotification) {
    let info = aNotification.userInfo
    let infoNSValue = info![UIKeyboardFrameBeginUserInfoKey] as NSValue
    let kbSize = infoNSValue.CGRectValue().size
    UIView.beginAnimations(nil, context: nil)
    UIView.setAnimationDuration(0.3)
    var rect : CGRect = self.view.frame
    rect.size.height += kbSize.height
    self.view.frame = rect
    UIView.commitAnimations()
}

一种更简单但通用的方法,就像苹果的做法一样,将键盘的高度考虑在内,这在我们使用键盘顶部的自定义工具栏时非常有用。尽管苹果在这方面的做法没有什么问题。

这是我的方法(略微修改了苹果的方法)-

// UIKeyboardDidShowNotification
- (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);
    self.scrollView.contentInset = contentInsets;
    self.scrollView.scrollIndicatorInsets = contentInsets;
}

// UIKeyboardWillHideNotification
- (void)keyboardWillBeHidden:(NSNotification*)aNotification
{
    UIEdgeInsets contentInsets = UIEdgeInsetsZero;
    self.scrollView.contentInset = contentInsets;
    self.scrollView.scrollIndicatorInsets = contentInsets;
}

我迟到了一点。您应该在viewController上添加scrollView。

您必须实现以下2种方法。

TextField委托方法。

    - (void)textFieldDidBeginEditing:(UIView *)textField {
    [self scrollViewForTextField:reEnterPINTextField];
}

然后在委托方法中调用以下方法。

 - (void)scrollViewForTextField:(UIView *)textField {
    NSInteger keyboardHeight = KEYBOARD_HEIGHT;

    if ([textField UITextField.class]) {
        keyboardHeight += ((UITextField *)textField).keyboardControl.activeField.inputAccessoryView.frame.size.height;
    } 

    CGRect screenFrame = [UIScreen mainScreen].bounds;
    CGRect aRect = (CGRect){0, 0, screenFrame.size.width, screenFrame.size.height - ([UIApplication sharedApplication].statusBarHidden ? 0 : [UIApplication sharedApplication].statusBarFrame.size.height)};
    aRect.size.height -= keyboardHeight;
    CGPoint relativeOrigin = [UIView getOriginRelativeToScreenBounds:textField];
    CGPoint bottomPointOfTextField = CGPointMake(relativeOrigin.x, relativeOrigin.y + textField.frame.size.height);

    if (!CGRectContainsPoint(aRect, bottomPointOfTextField) ) {
        CGPoint scrollPoint = CGPointMake(0.0, bottomPointOfTextField.y -aRect.size.height);
        [contentSlidingView setContentOffset:scrollPoint animated:YES];
    }
}

对于Swift程序员:

这将为您完成所有工作,只需将这些放在视图控制器类中,并将UITextFieldDelegate实现到视图控制器,并将textField的委托设置为self

textField.delegate = self // Setting delegate of your UITextField to self

实现委托回调方法:

func textFieldDidBeginEditing(textField: UITextField) {
    animateViewMoving(true, moveValue: 100)
}

func textFieldDidEndEditing(textField: UITextField) {
    animateViewMoving(false, moveValue: 100)
}

// Lifting the view up
func animateViewMoving (up:Bool, moveValue :CGFloat){
    let movementDuration:NSTimeInterval = 0.3
    let movement:CGFloat = ( up ? -moveValue : moveValue)
    UIView.beginAnimations( "animateView", context: nil)
    UIView.setAnimationBeginsFromCurrentState(true)
    UIView.setAnimationDuration(movementDuration )
    self.view.frame = CGRectOffset(self.view.frame, 0,  movement)
    UIView.commitAnimations()
}

对于Swift 4、4.2、5:改变

self.view.frame = CGRectOffset(self.view.frame, 0,  movement)

to

self.view.frame = self.view.frame.offsetBy(dx: 0, dy: movement)

关于此实现的最后一点注意事项:如果在显示键盘时将另一个视图控制器推到堆栈上,这将产生一个错误,其中视图返回到其中心框架,但键盘偏移未重置。例如,您的键盘是nameField的第一个响应者,但随后您按下一个按钮,将帮助视图控制器推到堆栈上。若要修复偏移错误,请确保在离开视图控制器之前调用nameField.issentFirstResponder(),确保同时调用textFieldDidEndEditing委托方法。我在viewWillDisappear方法中这样做。