toolkit/xre/nsINativeAppSupport.idl

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "nsISupports.idl"
   7
   8 /* nsINativeAppSupport
   9  *
  10  * This "pseudo" (in the XPCOM sense) interface provides for
  11  * platform-specific general application support:
  12  *  o It manages the details of the simple DDE communication
  13  *    supported on the Win32 platform (it is the addition of this
  14  *    item that prompted the creation of this interface.
  15  *
  16  * Due to the nature of the beast, this interface is not a full-blown
  17  * XPCOM component.  The primary reason is that objects that implement
  18  * this interface generally must be operational *before* XPCOM (or any
  19  * of the rest of Mozilla) are initialized.  As a result, this
  20  * interface is instantiated by somewhat unconventional means.
  21  *
  22  * To create the implementor of this interface, you call the function
  23  * NS_CreateNativeAppSupport.  This is done in the startup code
  24  * in nsAppRunner.cpp
  25  *
  26  * The interface provides these functions:
  27  *  start - You call this to inform the native app support that the
  28  *          application is starting.  In addition, it serves as a
  29  *          query as to whether the application should continue to
  30  *          run.
  31  *
  32  *          If the returned boolean result is PR_FALSE, then the
  33  *          application should exit without further processing.  In
  34  *          such cases, the returned nsresult indicates whether the
  35  *          reason to exit is due to an error or not.
  36  *
  37  *          Win32 Note: In the case of starting a second instance
  38  *                      of this executable, this function will return
  39  *                      PR_FALSE and nsresult==NS_OK.  This means that
  40  *                      the command line arguments have been
  41  *                      successfully passed to the instance of the
  42  *                      application acting as a DDE server.
  43  *
  44  *  stop - You call this to inform the native app support that the
  45  *         application *wishes* to terminate.  If the returned boolean
  46  *         value is PR_FALSE, then the application should continue
  47  *         (as if there were still additional top-level windows open).
  48  *
  49  *         Win32 Note: If this is the instance of the application
  50  *                     acting as the DDE server, and there are current
  51  *                     DDE conversations active with other instances
  52  *                     acting as DDE clients, then this function will
  53  *                     return PR_FALSE.
  54  *
  55  *  quit - Like Stop, but this method *forces* termination (or more
  56  *         precisely, indicates that the application is about to be
  57  *         terminated regardless of what a call to Stop might have
  58  *         returned.
  59  *
  60  *         This method is intended to be called when the user selects
  61  *         the "Quit" option (close all windows and exit).
  62  *
  63  *         Win32 Note: Stop is problematic in the case of "Quit" (close
  64  *                     all windows and exit the application) because
  65  *                     either we don't Quit or (potentially) we lose
  66  *                     requests coming from other instances of the
  67  *                     application.  The strategy is to give preference
  68  *                     to the user's explicit Quit request.  In the
  69  *                     unlikely event that a request is pending from
  70  *                     another instance of the application, then such
  71  *                     requests are essentially ignored.  This is
  72  *                     roughly equivalent to handling that request by
  73  *                     opening a new window, followed by immediately
  74  *                     closing it.  Since this is the same as if the
  75  *                     request came in immediately before the Quit
  76  *                     call (versus immediately after it), no harm.
  77  *
  78  *                     There is an exposure here: Upon return from this
  79  *                     function, any DDE connect request (for Mozilla)
  80  *                     will fail and other instances of the application
  81  *                     will start up as a DDE server.  In that case,
  82  *                     those instances may do things that conflict with
  83  *                     the subsequent shutting down of the instance that
  84  *                     is quitting.  For this reason, the call to Quit
  85  *                     should be deferred as long as possible.
  86  *
  87  *  onLastWindowClosing -  Called when the last window is closed. Used as a
  88  *                         "soft" shutdown, passwords are flushed.
  89  */
  90
  91 interface nsIXULWindow;
  92
  93 [scriptable, uuid(5fdf8480-1f98-11d4-8077-00600811a9c3)]
  94 interface nsINativeAppSupport : nsISupports {
  95     // Startup/shutdown.
  96     boolean start();
  97     void    enable();
  98     boolean stop();
  99     void    quit();
 100
 101     void onLastWindowClosing();
 102     void ReOpen();
 103 };