UITextView beginOfDocument返回nil [英] UITextView beginningOfDocument returns nil

问题描述

我必须在屏幕上获得 UITextView 中包含的字符串的位置。为了做到这一点，我试图得到相应的UITextPosition。问题是 UITextView 方法 startingOfDocument 返回 nil 同样 endOfDocuement ）。有人可以解释我为什么吗？

我的代码如下所示：

   - （UITextRange *）getRangeOfString：（NSString *）string inTextView：（UITextView *）tv 
 {
 UITextPosition * beginning = [tv positionFromPosition：tv.beginningOfDocument offset：[tv.text rangeOfString：string ]。位置]; 
 UITextPosition * end = [tv positionFromPosition：begin offset：[tv.text rangeOfString：string] .length]; 
 
 return（[tv textRangeFromPosition：beginning toPosition：end]）; 
} 
  

解决方案

，但请务必在Interface Builder中启用可选择属性。

贷记： http://jon-nolen.blogspot.com/2013/10/uitextview-returns-nil-for-uitextinput.html

I have to get the position on the screen of a string contained in a UITextView. To do that, I tried to get the corresponding UITextPosition(s). The problem is that the UITextView method beginningOfDocument returns nil (same for endOfDocuement). Could someone explain me why? And which solution I could use.

My code looks like this:

- (UITextRange *)getRangeOfString:(NSString *)string inTextView:(UITextView *)tv
{
    UITextPosition *beginning = [tv positionFromPosition:tv.beginningOfDocument offset:[tv.text rangeOfString:string].location];
    UITextPosition *end = [tv positionFromPosition:beginning offset:[tv.text rangeOfString:string].length];

    return ([tv textRangeFromPosition:beginning toPosition:end]);
}

解决方案

This is about a month late, but make sure you have the "selectable" property enabled in Interface Builder.

Credit: http://jon-nolen.blogspot.com/2013/10/uitextview-returns-nil-for-uitextinput.html

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