如何解决UITextView中的“自动滚动”?

时间:2018-01-18 15:25:51

标签: ios swift uitextview

我编写了一个函数scrollToVisible()来滚动UItextview中的文本,因为键盘覆盖了部分文本,或者光标不可见。但是UItextview可以在光标不在整个视图中但不可见时自动滚动文本,它仍然可以通过键盘自动滚动覆盖.UItextview的自动滚动可以中断我的scrollToVisible()。 因此,我可以禁止UItexview自动滚动吗?还是另一种解决“键盘盖”问题的方法?

我的scrollToVisible()函数

func scrollToVisible()
{
    let cursortop = self.EditArea.convert(self.EditArea.caretRect(for: (self.EditArea.selectedTextRange?.start)!).origin, to: self.view)
    var cursorbottom = cursortop
    cursorbottom.y += self.EditArea.caretRect(for: (self.EditArea.selectedTextRange?.start)!).height
    let bottom = UIScreen.main.bounds.size.height - self.EditArea.textContainerInset.bottom
    var contentOffset = self.EditArea.contentOffset
    if cursortop.y <= 85
    {
        contentOffset.y = contentOffset.y - 85 + cursortop.y
        self.EditArea.setContentOffset(contentOffset, animated: true)
    }
    else if cursorbottom.y >= bottom
    {
        contentOffset.y = contentOffset.y - bottom + cursorbottom.y
        self.EditArea.setContentOffset(contentOffset, animated: true)
    }
}

PS:此EditArea是textview

2 个答案:

答案 0 :(得分:1)

我遇到了类似的问题:当你打开键盘时,文本视图没有被调整,光标隐藏在键盘后面(或者你说&#34;覆盖&#34;光标)。因此,如果我按Enter键开始一个新行,它也不会显着地自动滚动(实际上它确实如此,但它在键盘后面)。我找到了一个解决方案,在我的网站上完美适合我:https://www.hackingwithswift.com/example-code/uikit/how-to-adjust-a-uiscrollview-to-fit-the-keyboard

使用swift 4从上述网站中提取的解决方案:

键盘出现时订阅事件并在viewDidLoad()功能中消失:

// For avoiding that the text cursor disappears behind the keyboard, adjust the text for it
let notificationCenter = NotificationCenter.default
notificationCenter.addObserver(self, selector: #selector(adjustForKeyboard), name: .UIKeyboardWillHide, object: nil)
notificationCenter.addObserver(self, selector: #selector(adjustForKeyboard), name: .UIKeyboardWillChangeFrame, object: nil)

使用此功能调整textview,将其添加到班级的任何位置:

// Adjusts the textView, so that the text cursor does not disappear behind the keyboard
@objc func adjustForKeyboard(notification: Notification) {
    let userInfo = notification.userInfo!

    let keyboardScreenEndFrame = (userInfo[UIKeyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
    let keyboardViewEndFrame = view.convert(keyboardScreenEndFrame, from: view.window)

    if notification.name == Notification.Name.UIKeyboardWillHide {
        textView.contentInset = UIEdgeInsets.zero
    } else {
        textView.contentInset = UIEdgeInsets(top: 0, left: 0, bottom: keyboardViewEndFrame.height, right: 0)
    }

    textView.scrollIndicatorInsets = textView.contentInset

    let selectedRange = textView.selectedRange
    textView.scrollRangeToVisible(selectedRange)
}

答案 1 :(得分:0)

这是我的解决方案,您只需在app delegate中编写一行代码就可以在app中处理任何textfield / textview

如果您使用的是pod,只需添加以下pod即可添加“IQKeyboardManager”pods

pod'IQKeyboardManagerSwift'

并在app delegate

中的didFinishLaunchingWithOptions中添加此行
  IQKeyboardManager.sharedManager().enable = true