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

雨燕5

在viewDidLoad或viewDidAppear中添加addKeyboardObserver方法。

fileprivate func addKeyboardObservers(){
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)

    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
}

fileprivate func removeKeyboardObservers(){
    NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillHideNotification, object: nil)
    NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillShowNotification, object: nil)
}


@objc fileprivate func keyboardWillHide(_ notification: Notification){
    if (window == nil) {return}
    guard let duration = (notification.userInfo?[UIResponder.keyboardAnimationDurationUserInfoKey] as? Double) else {return}

   scrollView.contentInset.bottom = .zero
}


@objc fileprivate func keyboardWillShow(_ notification: Notification){
    if (window == nil) {return}
    if UIApplication.shared.applicationState != .active { return }

    // keyboard height
    guard let height = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? CGRect)?.height else {return}
    // keyboard present animation duration
    guard let duration = (notification.userInfo?[UIResponder.keyboardAnimationDurationUserInfoKey] as? Double) else {return}

   scrollView.contentInset.bottom = height
}

不要忘记删除或消失观察者

    self.removeKeyboardObservers()

其他回答

我使用Swift和自动布局(但不能评论之前的Swift答案);以下是我在没有滚动视图的情况下的操作方法:

我在IB中使用字段之间的垂直约束来布局表单,以分隔它们。我在容器视图的最顶部字段中添加了一个垂直约束,并为此创建了一个出口(下面代码中的topSpaceForFormConstraint)。所有需要的就是更新这个约束,这是我在动画块中为一个漂亮的软运动所做的。当然,高度检查是可选的,在这种情况下,我只需要对最小的屏幕尺寸进行检查。

这可以使用任何常用的textFieldDidBegginEditing或keyboardWillShow方法调用。

func setFormHeight(top: CGFloat)
{
    let height = UIScreen.mainScreen().bounds.size.height

    // restore text input fields for iPhone 4/4s
    if (height < 568) {
        UIView.animateWithDuration(0.2, delay: 0.0, options: nil, animations: {
            self.topSpaceForFormConstraint.constant = top
            self.view.layoutIfNeeded()
            }, completion: nil)
    }

}

我不确定将视图上移是否是正确的方法。我用了不同的方式,调整了UIScrollView的大小。我在一篇小文章中详细解释了它。

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。

下面是带有文本字段的滚动视图的简单解决方案,不需要任何约束或活动文本字段等。。。

 override func viewWillAppear(_ animated: Bool){
        super.viewWillAppear(animated)
        registerForKeyboardNotifications();


    }
    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        deregisterFromKeyboardNotifications();
    }
    //MARK:- KEYBOARD DELEGATE METHODS
        func registerForKeyboardNotifications(){
            //Adding notifies on keyboard appearing
            NotificationCenter.default.addObserver(self, selector: #selector(keyboardWasShown(notification:)), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
            NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillBeHidden(notification:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
        }
        func deregisterFromKeyboardNotifications(){
            //Removing notifies on keyboard appearing
            NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillShow, object: nil)
            NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillHide, object: nil)
        }
        func keyboardWasShown(notification: NSNotification){

            var info = notification.userInfo!
            let keyboardSize = (info[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue.size
            var contentInset:UIEdgeInsets = self.scrRegister.contentInset
            contentInset.bottom = (keyboardSize?.height)!
            scrRegister.contentInset = contentInset


        }
        func keyboardWillBeHidden(notification: NSNotification)
        {
            var contentInset:UIEdgeInsets = self.scrRegister.contentInset
            contentInset.bottom = 0
            scrRegister.contentInset = contentInset

        }

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()
}