Modeless window using "palette" does not stay up in CS5

Question

I am having trouble running a modeless dialog with CS5 (on Windows 64-bit).  My own script does not stay up and neither does the SnpCreateDialog.jsx snippet that  comes with the ESTK and is supposed to demonstrate modeless dialogs.  I have  tried:
Running from the Scripts panel
Add #target photoshop
Being sure the drop-down menu says Photoshop, not CTSK
as suggested in an older discussion at http://forums.adobe.com/message/3008230#3008230.  (I decided to make a new discussion as that one was marked answered.)
It also does not stay up when moved into the Photoshop Scripts folder and run from the File menu in Photoshop.
The relevant code in SnpCreateDialog.jsx is:
function SnpCreateDialog()
     this.windowRef = null;
Functional part of this snippet.
Create a window of type "palette" (a modeless dialog) and display it.
@return True if the snippet ran as expected, false otherwise.
@type Boolean
SnpCreateDialog.prototype.run = function()
     // Create a window of type palette.
     var win = new Window("palette", "SnpCreateDialog",[100,100,380,245]);  // bounds = [left, top, right, bottom]
     this.windowRef = win;
     // Add a frame for the contents.
     win.btnPanel = win.add("panel", [25,15,255,130], "SnpCreateDialog");
     // Add the components, two buttons
     win.btnPanel.okBtn = win.btnPanel.add("button", [15,65,105,85], "OK");
     win.btnPanel.cancelBtn = win.btnPanel.add("button", [120, 65, 210, 85], "Cancel");
     // Register event listeners that define the button behavior
     win.btnPanel.okBtn.onClick = function() {
          $.writeln("OK pressed");
          win.close();
     win.btnPanel.cancelBtn.onClick = function() {
          $.writeln("Cancel pressed");
          win.close();
     // Display the window
     win.show();
     return true;
"main program": construct an anonymous instance and run it
  as long as we are not unit-testing this snippet.
if(typeof(SnpCreateDialog_unitTest) == "undefined") {
    new SnpCreateDialog().run();
If  I put a breakpoint on the "return true;" line, then I can see that the dialog has, in fact, been created and is visible, but it has returned from win.show() and will go away as soon as the script continues.
Any help would be appreciated.

Answer 1

Kenneth Evans wrote:
The advantage of a modeless dialog is that you can continue to do things in Photoshop while the dialog is up.  At least I presume so, since I haven't got one to work, including the ESTK example.
Sorry but no, most of the Photoshop UI is disabled while a script is running even if the script displays a palette window.
A dialog window does wait for show() to complete. That is what makes dialogs modal. A palette window does not wait for show() to complete. It runs the rest of the script.
In the example you posted all the script does after showing the window is return true then ends. Which is why all it does is flash the window. If you put a $.sleep(1000) line before the return true line the windows will display until sleep timeouts then the script will end and the window will close. That is why with Photoshop palette windows are really only useful for progress bars or other script status type windows.
Although palette windows may allow the user to intreact with the app UI while the window is displayed that doesn't work with Photoshop. The window only displays while the script is running and a running script limits Photoshop UI interaction.
I have tested palette windows in CS2, CS3, CS4, and CS5 with the same results. The window only shows while the script is running.
With Photoshop if you want the user to interact with the UI you have to create a panel.