TIP #25: NATIVE TK_MESSAGEBOX  ON MACINTOSH 
=============================================
 Version:      $Revision: 1.3 $
 Author:       Mats Bengtsson <matben_at_privat.utfors.se>
 State:        Withdrawn
 Type:         Project
 Tcl-Version:  8.5
 Vote:         Pending
 Created:      Wednesday, 07 February 2001
 URL:          https://tip.tcl-lang.org25.html
 Post-History: 
 Obsoleted-By: TIP #152

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 ABSTRACT 
==========

 This is a replacement for the /tk_messageBox/ on the Macintosh with a 
 native implementation which is compliant with the Appearance Manager in 
 Mac OS 8 and later. 

 RATIONALE 
===========

 The present (in 8.3.2p1 and earlier) /tk_messageBox/ on the Macintosh 
 is non-movable, and lacks many features that are required to be 
 compliant with Mac OS 8 and later. Non-movable dialogs should be 
 abandoned in a multitasking environment. This TIP presents a step to 
 extend the native appearance on the Macintosh. 

                    +-----------------------------+
                    |+-+ Map 'itemHit' (1,2,3) to |
                    ||?| descriptive text string. |
                    |+-+                          |
                    | ,-----.  ,----.  ,--------. |
                    | | Yes |  | No |  | Cancel | |
                    | `-----'  `----'  `--------' |
                    +-----------------------------+
                    
                    (This text representation does
                    not do justice to the original)

                   This is the present tk_messageBox.

             +-------------------------------------------+
             +-------------------------------------------+
             | +-+  Map 'itemHit' (1,2,3) to descriptive |
             | |?|  text string.                         |
             | +-+                                       |
             |      ,--------.         ,----.   ,=====.  |
             |      | Cancel |         | No |   | Yes |  |
             |      `--------'         `----'   `====='  |
             +-------------------------------------------+
             
                   (This text representation does
                   not do justice to the original)

                   This is the native tk_messageBox.

 REFERENCE IMPLEMENTATION 
==========================

 The proposed change is now implemented as a loadable extension (in C) 
 on Macintosh, and can be downloaded at 
 <URL:http://hem.fyristorg.com/matben/download/MovableAlerts.sit> . This 
 extension requires Tk 8.3.2p1 or later due to the changed stub loading 
 mechanism. The core of the code should go in the /tkMacDialog.c/ file. 
 Some additional changes are necessary in order to load the new 
 /tk_messageBox/ and not the old, script based /tk_messageBox/. Also, 
 need to check for the presence of the Appearance manager: 

   if (Appearance Manager)
       use native (new) messageBox
   else
       use present script based messageBox

 All functionality from the documentation that are applicable are 
 implemented, with some exceptions: 

     *  There is a /-finemessage/ option to support the native text 
       message set in a smaller font below the main message. 

     *  Both /-message/ and /-finemessage/ option are truncated at 255 
       characters. 

     *  Buttons appear from right to left instead of vice versa. 

     *  There is always a default button.  

 All these deviations are consistent with the look-and-feel of Mac OS 
 8.0 and on. Existing scripts using /tk_messageBox/ are compatible with 
 the new /tk_messageBox/. 

 Open questions:  

     *  Name of extra option /-finemessage/ 

     * Name of the two C functions in the implementation 

     * How to make the core code call the new code instead of the 
       original, script implemented 

 COPYRIGHT 
===========

 This document has been placed in the public domain 

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