How could I display a dialog attached to a window?

I saw what you did there...

You don't necessarily need to create another window for simple alerts, you can use the NSAlert class. I think there is still some weirdness with sheets, so the easiest way to do a sheet would be to use Myriad Helpers, which has a category that adds some methods to the NSAlert class, for example:

tell Cocoa's NSAlert's makeAlert_buttons_text_("Alert", {"OK"}, "Hiya,  Apple_For_The_Win" & return & "This sheet will give up after 10 seconds")   showOver_calling_wait_(mainWindow, {"sheetDismissed:", me}, 10) end tell -- on sheetDismissed_(theButton) -- the sheet has been dismissed   # whatever end sheetDismissed_

The completion handler (sheetDismissed in this case) is called when the sheet is dismissed, and is passed the name of the button (or 'Gave Up').

As far as I know there is still a problem with AppleScriptObjC using sheets, so some kind of Objective-C protocol or category will be needed. Using Myriad Helpers is pretty easy, and you can just just use what you need - for the alert sheet, just add the NSAlert+MyriadHelpers .h and .m files to your project and you are good to go.

Looks like you snuck an edit in there...

For just a regular alert you can do something like:

tell Cocoa's NSAlert's alertWithMessageText_defaultButton_alternateButton_otherButton_informativeTextWithFormat_("This is an alert", "OK", "Cancel", missing value, "Hello Apple_For_The_Win") to set theChoice to its runModal()   if theChoice is Cocoa's NSAlertDefaultReturn then -- OK button     # whatever on OK   else if theChoice is Cocoa's NSAlertAlternateReturn then -- Cancel     # whatever on Cancel   end if

Edit:

I've also used a handler for a simple alert with just an OK button:

on showAlert_withMessage_(alertTitle, alertMessage) -- show a simple alert   tell Cocoa's NSAlert's alloc's init()     setMessageText_(alertTitle)     setInformativeText_(alertMessage)     return runModal()   end tell end showAlert_withMessage_

Oops, sorry about that. Cocoa is a shortcut I use for current application. You can define a property like:

propertyCocoa : current application

or just replace "Cocoa" with "current application".

Edit:

I'm pulling most of these examples from my Windows and Panels example project - it can be downloaded here.

Well, that is a sheet, so you are wanting to fake a sheet without using a sheet? For a sheet with anything other than a simple alert you are looking at a custom panel or window (which AppleScript's display dialog is, after all).

Well, the easiest way would be to use an alert as a sheet - is there a particular reason you don't want to use the Myriad Helper category?

The alert sheet example in my first reply is modal. There is another method in the category that doesn't have a timeout - it would just be:

showOver_calling_(mainWindow, {"sheetDismissed:", me})