How to display modal window using osascript or AppleScript in OS X

How to display modal(over all apps, windows) window using osascript or AppleScript in OS X 10.6.8 and later.

Here a script I do:

#!/bin/bash

osascript -e 'tell app "System Events" to display dialog "My Dialog" buttons {"OK"} default button 1 with title "My Dialog" with icon caution'

The problem is that it's not modal.

How to fix the following issue?

I wrote a script recently to monitor my macbook battery when it got low. To make sure I didn't miss the alert I did the following...

repeat while true
    me activate
    set userResp to display dialog ¬
        "Yes or No?" as text buttons {"No", "Yes"} ¬
        default button "Yes" with icon caution ¬
        with title "Question" giving up after 5
end repeat

The code will keep redisplaying the message even if I accidentally click elsewhere and it gets buried under another window.

Hope that helps.

You can use the "display notification" command to place a notification above all other windows (and into Notification Center,) but you can’t block the user from using their computer.