FLEX光标定位和插入文本

因为目前的FLEX的RichTextEditor不支持图文混编，所以，只能自己动手了，实现最核心的部分，光标定位插入文本。

MXML代码

<?xml version="1.0" encoding="utf-8"?gt;
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute"gt;
 <mx:Script>
  <![CDATA[

   [Bindable]
   private var textAreaString:String = "textAreaString";
   [Bindable]
   private var insertString:String = "|insert|";

   private function insertHandler():void {
    if (textArea.selectionBeginIndex == textArea.selectionEndIndex) {
     var startPart:String = textAreaString.substring(0,textArea.selectionBeginIndex);
     var endPart:String = textAreaString.substring(textArea.selectionEndIndex,textAreaString.length);
     startPart+=insertString;
     startPart+=endPart;
     textAreaString = startPart;
    }
   }

   private function changeInsertHandler():void {
    insertString = insertInput.text;
   }
  ]]>
 </mx:Script>
 <mx:TextArea id="textArea" x="10" y="21" width="298" height="158" text="{textAreaString}"/gt;
 <mx:Button x="316" y="20" label="Insert" click="insertHandler();"/gt;
 <mx:TextInput id="insertInput" x="316" y="50" text="{insertString}" change="changeInsertHandler();"/gt;
</mx:Application>