widget/nsIDragSession.idl
author Nicholas Nethercote <nnethercote@mozilla.com>
Wed, 25 Oct 2017 10:22:38 +1100
changeset 387909 3d0093f961eec929caa370444cd0f7fcbfbc82bc
parent 327221 03fd23542c4fb4503e635f4b185f2795a3c61a97
child 403046 fc5cbc7e0d7ff28ed81f802a4973e2e8634cfe61
permissions -rw-r--r--
Bug 1410794 - Change some |string| occurrences in nsIPrefBranch.idl to |ACString|. r=erahm. This makes the code nicer. In particular, it removes many getter_Copies() calls. The patch also converts a lot of nsCStrings to nsAutoCString, which will avoid heap allocation in the common case. The patch also renames PREF_CopyCharPref() as PREF_GetCStringPref(), because it's actually getting a string, not a char, and that matches the existing GetCString() and GetDefaultCString() methods. Correspondingly, it also renames PREF_SetCharPref() as PREF_SetCStringPref(). The |aPrefName| arguments in nsIPrefBranch.idl remain as |string| because they almost always involve passing in C string literals, and passing "foo" is much nicer than passing NS_LITERAL_CSTRING("foo"). It's worth noting that early versions of this patch used |AUTF8String| instead of |ACString|. But it turns out that libpref stores prefs internally as Latin1. And |ACString| is compatible with Latin1 but |AUTF8String| isn't, because non-ASCII Latin1 strings are not valid UTF-8!

/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsISupports.idl"
#include "nsITransferable.idl"


%{ C++
#include "nsSize.h"
%}

native nsSize (nsSize);


interface nsIDOMDocument;
interface nsIDOMNode;
interface nsIDOMDataTransfer;

[scriptable, uuid(25bce737-73f0-43c7-bc20-c71044a73c5a)]
interface nsIDragSession : nsISupports
{
  /**
    * Set the current state of the drag, whether it can be dropped or not.
    * usually the target "frame" sets this so the native system can render the correct feedback
    */
  attribute boolean canDrop;

  /**
   * Indicates if the drop event should be dispatched only to chrome.
   */
  attribute boolean onlyChromeDrop;
  
  /**
    * Sets the action (copy, move, link, et.c) for the current drag 
    */ 
  attribute unsigned long dragAction;
  
  /**
    * Sets the current width and height of the drag target area. 
    * It will contain the current size of the Frame that the drag is currently in
    */  
  [noscript] attribute nsSize targetSize;
 
  /**
    * Get the number of items that were dropped
    */
  readonly attribute unsigned long numDropItems;
  
  /**
    * The document where the drag was started, which will be null if the
    * drag originated outside the application. Useful for determining if a drop
    * originated in the same document.
    */
  readonly attribute nsIDOMDocument sourceDocument;

  /**
    * The dom node that was originally dragged to start the session, which will be null if the
    * drag originated outside the application.
    */
  readonly attribute nsIDOMNode sourceNode;

  /**
   * The data transfer object for the current drag.
   */
  attribute nsIDOMDataTransfer dataTransfer;

  /**
    * Get data from a Drag&Drop. Can be called while the drag is in process
    * or after the drop has completed.  
    *
    * @param  aTransferable the transferable for the data to be put into
    * @param  aItemIndex which of multiple drag items, zero-based
    */
  void getData ( in nsITransferable aTransferable, in unsigned long aItemIndex ) ;

   /**
    * Check to set if any of the native data on the clipboard matches this data flavor
    */
  boolean isDataFlavorSupported ( in string aDataFlavor ) ;

  void userCancelled();

  void dragEventDispatchedToChildProcess();

  // Called when nsIDragSession implementation should update the UI for the
  // drag-and-drop based on the data got from the child process in response to
  // NS_DRAGDROP_OVER sent from parent process to child process.
  void updateDragEffect();

  // Change the drag image, using similar arguments as
  // nsIDragService::InvokeDragSessionWithImage.
  void updateDragImage(in nsIDOMNode aImage, in long aImageX, in long aImageY);
};


%{ C++

%}