Make EditText only allow numbers?

example

// DIALOG
// ======
 dialog = new Window("dialog"); 
    dialog.text = "EDITTEXT INSERT ONLY NUMBERS"; 
    dialog.orientation = "column"; 
    dialog.alignChildren = ["center","top"]; 
    dialog.spacing = 10; 
    dialog.margins = 16; 
 statictext1 = dialog.add("statictext"); 
    statictext1.text = "ALERT INSERT ONLY NUMBERS"; 
// GROUP1
// ======
 group1 = dialog.add("group"); 
    group1.orientation = "row"; 
    group1.alignChildren = ["left","center"]; 
    group1.spacing = 10; 
    group1.margins = 0; 
 TEST_NUMBER = group1.add("edittext"); 
    TEST_NUMBER.text = ""; 
 TEST_NUMBER.addEventListener ('keydown', NumericEditKeyboardHandler);
// DIALOG
// ======
 button1 = dialog.add("button"); 
    button1.text = "CLOSE"; 
    button1.justify = "center"; 
    
    
 button1.onClick = function () {
     dialog.close();
     }
dialog.show();
/// FUNCTION
function NumericEditKeyboardHandler (event) {
    try {
        var keyIsOK = KeyIsNumeric (event) ||
  KeyIsDelete (event) ||
  KeyIsLRArrow (event) ||
  KeyIsTabEnterEscape (event);
        if (! keyIsOK) {
            //    Bad input: tell ScriptUI not to accept the keydown event
            event.preventDefault();
            /*    Notify user of invalid input: make sure NOT
       to put up an alert dialog or do anything which
                 requires user interaction, because that
                 interferes with preventing the 'default'
                 action for the keydown event */
          // app.beep();
              alert("CAUTION!!!   \nCAN YOU ENTER NUMBERS ONLY?");
        }
    }
    catch (e) {
        ; // alert ("Ack! bug in NumericEditKeyboardHandler: " + e);
    }
}
function DesmalEditKeyboardHandler (event) {
    try {
        var keyIsOK = KeyIsNumeric (event) ||
  KeyIsPeriod (event) ||
  KeyIsDelete (event) ||
  KeyIsLRArrow (event) ||
  KeyIsTabEnterEscape (event);
        if (! keyIsOK) {
            //    Bad input: tell ScriptUI not to accept the keydown event
            event.preventDefault();
            /*    Notify user of invalid input: make sure NOT
       to put up an alert dialog or do anything which
                 requires user interaction, because that
                 interferes with preventing the 'default'
                 action for the keydown event */
           // app.beep();
            alert("CAUTION!!!   \nCAN YOU ENTER NUMBERS ONLY?");
        }
    }
    catch (e) {
        ; // alert ("Ack! bug in NumericEditKeyboardHandler: " + e);
    }
}
//    key identifier functions
function KeyHasModifier (event) {
    return event.shiftKey || event.ctrlKey || event.altKey || event.metaKey;
}
function KeyIsNumeric (event) {
    return  (event.keyName >= '0') && (event.keyName <= '9') && ! KeyHasModifier (event);
}
function KeyIsPeriod (event) {
    return  (event.keyName == 'Period') && ! KeyHasModifier (event);
}
function KeyIsDelete (event) {
    //    Shift-delete is ok
    return ((event.keyName == 'Backspace') || (event.keyName == 'Delete')) && ! (event.ctrlKey);
}
function KeyIsLRArrow (event) {
    return ((event.keyName == 'Left') || (event.keyName == 'Right')) && ! (event.altKey || event.metaKey);
}
function KeyIsTabEnterEscape (event) {
    return event.keyName == 'Tab' || event.keyName == 'Enter' || event.keyName == 'Escape';
}

X is an extremely talented Photoshop scripter where I'm just a hacker that just hacks small scripts to do what I want done.   I created a small script a while back  to tile images onto a canvas. Data required is numeric.   I don't know Photoshop ScriptUI and those that do are annoyed at Adobe for not fixing bugs they report.  So I just steal their dialogs and smash them into what I want.and  hopefully avoid the bugs.  When I  create the dialog it would accept any values. I wanted to allow only numeric data so after doing some searching I think if i remember correctly I found some code I believe Michael Hale posted to handle the keyboard. I added that code to my small script.  You may have a easier time find our how to do what you want to do looking at a small script.   Contact Sheet II.jsx is huge.  How things fit may be harder to see in there. http://www.mouseprints.net/old/dpr/PasteImageRoll.jsx  If the uses enter anything other the a number or . and some edit keys like backspace in a numeric files they receive a beep and the key is not accepted.

Check out the Contact Sheet II.jsx script that comes with PS. It has key filtering stuff in it. Ignore the stuff for handling the Enter key: it's there to validate the form before processing.