Cursor (caret) position within EditText

[cswaim080880]

Hey guys,

Not sure if this is possible but I'm curious if there is a way to determine the position of the cursor in the EditText?  I know you can insert anything at the point of the cursor (or selection) with EditText.textselection.  What I'm interested in doing is figuring out the position of the cursor so that I can compare the text before the cursor to the text after the cursor.  Basically I want my program to be able to look at inputted text and determine if, when typing in an opening brace ( { ) that there isn't already a closing brace ( } ) and if there isn't, automatically add one.  I want to implement my own version of auto complete with some other custom solutions rolled in.

Thanks!

Calvin

[Christian Lett]

The onChanging event fires every time you make a keystroke in an EditText control. You could keep a copy of the text in a variable outside the scope of the event function (or a global) and compare the two. The difference would always be one character, so you should be able to find the current position.

This kind of works, but there are probably better ways to find the difference:

{

     var dlg = new Window("dialog", "test");

     var txtEdit = dlg.add("edittext", [10, 10, 500, 100], "", {multiline: true});

     var txtInfo = dlg.add("statictext", [10, 110, 500, 120]);

     var oldText = "";

     txtEdit.onChanging = function() {

          var info = "Cursor is at char position ";

          var pos = 0;

          for(var i=0; i<this.text.length; i++) {

               var chCur = this.text.charAt(i);

               var chOld = oldText.charAt(i);

               if(chCur !== chOld) {

                    pos = i + 1;

                    break;

               }

               if(pos === 0) {

                    pos = this.text.length;

               }

          }

          info += pos.toString();

          txtInfo.text = info;

          oldText = this.text;

     };

     dlg.show();

}

[cswaim080880]

Hey Christian,

This is actually a great solution...definitely out of the box thinking.  It usually takes a brute force solution when a language/architecture leaves out certain useful functionality.  I'm gonna play around with this for sure! 

Calvin

[David Torno]

EditText elements have a "textselection" attribute that you can use to insert text at cursor point. I use this on my ExtendScript Developer Utility script for the code writing area.

Here's an example showing it in action. Just place your cursor in the second edittext box anywhere and click the Insert button. Also try selecting some text and clicking Insert.

var win = new Window("palette", "Name", undefined);
var et = win.add("edittext", undefined, "New text");
et.characters = 30;
var insert = win.add("button", undefined, "Insert");
var et2 =  win.add("edittext", undefined, "Old text");
et2.characters = 30;
var close = win.add("button", undefined, "Close");


insert.onClick = function(){
  if(et2.textselection.length > 0){     //Checks the length of selected characters
  et2.textselection = et.text + et2.textselection;     //Inserts new text in front of the old selected text
  }else{
  et2.textselection = et.text;     //Simply inserts the new text at the current cursor position
  }
}


win.center();
win.show();

[cswaim080880]

Thanks David.  I had checked out textselection and unfortunately it doesn't fully cover the functionality I need.  I want to eventually use the textselection to insert but I need to know where I am in the text so I can search forwards and backwards for certain patterns to close.  I think between Christian's idea and yours it'll cover what I need.