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

我最近发现自己在开发消息应用程序时也遇到了类似的情况。我创建了一个自定义的UIView,它粘在键盘顶部,并自动完成您所需的大部分操作

消息生成器视图

(来源:thegamengine.org)

这个项目背后的想法是创建类似于iMessage合成视图AKA的功能:

当键盘关闭时,会粘在键盘顶部并移动到屏幕底部处理文本中的更改控制柄旋转

为了调整/重新配置UIScrollView,您需要使用以下可选委托方法:

-(void)messageComposerFrameDidChange:(CGRect)帧,动画持续时间:(float)持续时间;

每当更改帧(调整大小、重新定位、旋转)时都会调用它,并且还会提供动画持续时间。您可以根据需要使用此信息调整UIScrollView的框架和内容插图的大小。

其他回答

在(BOOL)textFieldShouldBeginEditing:(UITextField*)textField中

if (textField.frame.origin.y > self.view.frame.size.height - 216)
    {
        if (screenHeight>500)
            scrollView.contentSize = CGSizeMake(0.0, scrollView.contentSize.height + 100);
        else
            scrollView.contentSize = CGSizeMake(0.0, scrollView.contentSize.height + 216);
        CGPoint scrollPoint = CGPointMake(0.0,(textField.frame.origin.y - (self.view.frame.size.height - 216 - textField.frame.size.height - 20)));
        [scrollView setContentOffset:scrollPoint animated:YES];
    }
    [scrollView setScrollEnabled:YES];

辞职时,你需要写以下代码

scrollView.contentSize = CGSizeMake(0.0, 640);
CGPoint scrollPoint = CGPointMake(0.0,0.0);
[scrollView setContentOffset:scrollPoint animated:YES]; 

这将非常有效。滚动视图可以根据文本字段位置自动调整。我相信你会感觉很好

static const CGFloat KEYBOARD_ANIMATION_DURATION = 0.25;
static const CGFloat MINIMUM_SCROLL_FRACTION = 0.2;
static const CGFloat MAXIMUM_SCROLL_FRACTION = 0.8;
static const CGFloat PORTRAIT_KEYBOARD_HEIGHT = 216;
static const CGFloat LANDSCAPE_KEYBOARD_HEIGHT = 162;
@interface LoginVC ()
{
  CGFloat animatedDistance;
   CGRect viewFrameKey;
}

 //In ViewDidLoad
   viewFrameKey=self.view.frame;



- (void)textFieldDidBeginEditing:(UITextField *)textField
{
CGRect textFieldRect =
[self.view.window convertRect:textField.bounds fromView:textField];
CGRect viewRect =
[self.view.window convertRect:self.view.bounds fromView:self.view];
CGFloat midline = textFieldRect.origin.y + 0.5 * textFieldRect.size.height;
CGFloat numerator =
midline - viewRect.origin.y
- MINIMUM_SCROLL_FRACTION * viewRect.size.height;
CGFloat denominator =
(MAXIMUM_SCROLL_FRACTION - MINIMUM_SCROLL_FRACTION)
* viewRect.size.height;
CGFloat heightFraction = numerator / denominator;
if (heightFraction < 0.0)
{
    heightFraction = 0.0;
}
else if (heightFraction > 1.0)
{
    heightFraction = 1.0;
}
UIInterfaceOrientation orientation =
[[UIApplication sharedApplication] statusBarOrientation];
if (orientation == UIInterfaceOrientationPortrait ||
    orientation == UIInterfaceOrientationPortraitUpsideDown)
{
    animatedDistance = floor(PORTRAIT_KEYBOARD_HEIGHT * heightFraction);
}
else
{
    animatedDistance = floor(LANDSCAPE_KEYBOARD_HEIGHT * heightFraction);
}
CGRect viewFrame = self.view.frame;
viewFrame.origin.y -= animatedDistance;

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

[self.view setFrame:viewFrame];

[UIView commitAnimations];
}

- (void)textFieldDidEndEditing:(UITextField *)textField
{
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];
[self.view setFrame:viewFrameKey];
[UIView commitAnimations];
}

仅使用文本字段:

1a)使用界面生成器:选择所有文本字段=>编辑=>嵌入=>滚动视图

1b)在UIScrollView中手动嵌入文本字段,称为scrollView

2) 设置UITextFieldDelegate

3) 设置每个textField.delegate=self;(或在Interface Builder中建立连接)

4) 复制/粘贴:

- (void)textFieldDidBeginEditing:(UITextField *)textField {
    CGPoint scrollPoint = CGPointMake(0, textField.frame.origin.y);
    [scrollView setContentOffset:scrollPoint animated:YES];
}

- (void)textFieldDidEndEditing:(UITextField *)textField {
    [scrollView setContentOffset:CGPointZero animated:YES];
}

如果该文本字段位于表的单元格中(即使table.scrollable=NO),也可以轻松自动完成。

注意:桌子的位置和大小必须合理。例如:如果桌子的y位置是从视图底部算起的100,那么300高的键盘将覆盖整个桌子。如果表的高度为10,并且当键盘出现时,其中的文本字段必须向上滚动100才能可见,那么该文本字段将超出表的范围。

在textFieldDidBginEditing和textFieldDidEndEditing中调用函数[self-animateTextField:textField up:YES],如下所示:

-(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 = -130; // tweak as needed
    const float movementDuration = 0.3f; // tweak as needed

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

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

我希望这段代码对你有所帮助。

雨燕5

func animateTextField(textField: UITextField, up: Bool) {
    
    let movementDistance: CGFloat = -130
    let movementDuration: Double = 0.3
    
    var movement:CGFloat = 0
    if up {
        movement = movementDistance
    } else {
        movement = -movementDistance
    }
    
    UIView.animate(withDuration: movementDuration, delay: 0, options: [.beginFromCurrentState]) {
        self.view.frame = self.view.frame.offsetBy(dx: 0, dy: movement)
    }
}

func textFieldDidBeginEditing(_ textField: UITextField) {
    animateTextField(textField: textField, up: true)
}

func textFieldDidEndEditing(_ textField: UITextField) {
    animateTextField(textField: textField, up: false)
}