UITextView selectedRange在编程设置时不显示 [英] UITextView selectedRange not displaying when set programatically

问题描述

我的问题是，通过程序设置UITextView的selectedRange 选择文本，但 不会 直观地指示它已被选中。这听起来像是OS 3.0 / 3.1中的错误。更重要的是，任何解决方案或建议获得选择显示？ （示例项目链接在邮件底部）

My problem is that programatically setting the selectedRange of UITextView selects the text, but does not visually indicate it's selected. Does this sound like a bug in OS 3.0/3.1. More importantly, any solution or suggestions for getting the selection to display? (sample project linked at bottom of message)

我如何知道它是选择的，因为我没有得到视觉反馈？两个原因： / p>

How do I know it's selected since I'm not getting visual feedback? Two reasons:

1. 不闪烁光标


2. 点击键盘上的任何键可删除选择范围内的现有文字。 li>
   

1. No blinking cursor
2. Tapping any key on keyboard deletes existing text in the selection range.

我在viewcontroller中有一个UITextView，允许编辑一个用户可变的值。当在表格行上接收到双击时，或者用户轻敲行上的详细公开按钮时，编辑器控制器打开。 viewcontroller通过presentModalViewController到达，在编辑器VC的viewWillAppear方法中，我用 [self.textView becomeFirstResponder];

I have a UITextView in a viewcontroller which allows editing a user-changeable value. The editor controller is opened when a double-tap is received on a table row, or the user taps the detail disclosure button on a row. The viewcontroller arrives via presentModalViewController, and in the editor VC's viewWillAppear method, I initiate the keyboard with [self.textView becomeFirstResponder];

有时，我想启动编辑器，其中textview的所有内容选择，所以用户可以只是开始输入，它会删除现有的内容（这是因为我创建了新的项目与默认标题，所以几乎肯定用户将首先删除编辑器文本字段的全部内容，然后键入其标题）。

At times I want to start the editor with the entire contents of the textview selected so the user could simply start typing and it would delete the existing contents (this is because I create new items with default titles so it's almost certain the user will first delete the entire contents of the editor text field, then type their title).

我已经尝试的一些东西：

1. 在viewDidAppear中设置所选范围（而不是在textViewDidBeginEditing中执行此操作）。


2. 使用文本的副本替换_textView.text，然后应用selectedRange（在textViewDidBeginEditing中）...或许如果我处理框架错误，这可能会绕过它。


3. [[_ textView webView] selectAll]; （private api）。相同的行为，文本被选择没有视觉反馈。
发送_textView setNeedsDisplay和setNeedsLayout。

4. 使用performSelector ... afterDelay设置selectedRange，使其在退出textViewDidBeginEditing后发生。

1. setting the selected range in viewDidAppear (instead of and in addition to doing it in textViewDidBeginEditing).
2. Replacing _textView.text with a copy of the text in it then applying the selectedRange (in textViewDidBeginEditing)... thinking maybe if I'm dealing with framework bug, this might get around it.
3. [[_textView webView] selectAll]; (private api). same behavior, text gets selected with no visual feedback.
4. sending _textView setNeedsDisplay and setNeedsLayout.
5. using a performSelector ... afterDelay to set the selectedRange so that it happens after exiting textViewDidBeginEditing.

参考SO： 此处和此处

// UITextFieldDelegate Methods...
- (void)textViewDidBeginEditing:(UITextView *)_textView
{
 NSInteger len = [_textView.text length];

 if( self.selectInitialText ){
  //NOTE: this is not working as expected. Indeed the text is 
  // selected but the highlighting of the text isn't showing.
  _textView.selectedRange = NSMakeRange(0,len);
 }
}

- EDIT -

下面是提交到Apple BugReporter的示例项目。 下载BugReport_7380723示例项目

-- EDIT --
Here's the sample project submitted to Apple BugReporter. Download BugReport_7380723 sample project

其他信息：

在创建和播放示例项目提交时，我发现了两件事：

While creating and playing with the sample project submission, I discovered two things:

• 如果选择了文字但未显示高亮显示，请点按一些按键，然后点击摇动即可撤消，并恢复原始文字 >高亮显示。

• When there's text selected but no highlight displayed, tap some keystrokes then "shake to undo" and the original text is restored but IS highlighted.

如果在文本视图中手动选择，请点击选择全部按钮[指上面链接的示例项目]

If you manually make a selection in the textview, then tap the "Select All" button [refers to the sample project linked above], all text is selected AND displays the highlight properly.

推荐答案

在textView上以编程方式设置选择之前，只需调用select即可显示新选择。例如：

Before setting the selection programmatically on the textView, just call select to make it show the new selection visually. For example:

[textView select:self];
textView.selectedRange = newSelectedRange; 

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