nscontextmenu.js

现在很火的邮件客户端软件thunderbird的源码

# -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
# ***** BEGIN LICENSE BLOCK *****
# Version: MPL 1.1/GPL 2.0/LGPL 2.1
#
# The contents of this file are subject to the Mozilla Public License Version
# 1.1 (the "License"); you may not use this file except in compliance with
# the License. You may obtain a copy of the License at
# http://www.mozilla.org/MPL/
#
# Software distributed under the License is distributed on an "AS IS" basis,
# WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
# for the specific language governing rights and limitations under the
# License.
#
# The Original Code is Mozilla Communicator client code, released
# March 31, 1998.
#
# The Initial Developer of the Original Code is
# Netscape Communications Corporation.
# Portions created by the Initial Developer are Copyright (C) 1998
# the Initial Developer. All Rights Reserved.
#
# Contributor(s):
#   William A. ("PowerGUI") Law <[e-mail]>
#   Blake Ross <[e-mail]>
#   Gervase Markham <[e-mail]>
#
# Alternatively, the contents of this file may be used under the terms of
# either the GNU General Public License Version 2 or later (the "GPL"), or
# the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
# in which case the provisions of the GPL or the LGPL are applicable instead
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# the provisions above, a recipient may use your version of this file under
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# ***** END LICENSE BLOCK *****

/*------------------------------ nsContextMenu ---------------------------------
|   This JavaScript "class" is used to implement the browser's content-area    |
|   context menu.                                                              |
|                                                                              |
|   For usage, see references to this class in navigator.xul.                  |
|                                                                              |
|   Currently, this code is relatively useless for any other purpose.  In the  |
|   longer term, this code will be restructured to make it more reusable.      |
------------------------------------------------------------------------------*/


function nsContextMenu( xulMenu ) {
    this.target         = null;
    this.menu           = null;
    this.popupURL       = null;
    this.onTextInput    = false;
    this.onImage        = false;
    this.onLoadedImage  = false;
    this.onLink         = false;
    this.onMailtoLink   = false;
    this.onSaveableLink = false;
    this.onMetaDataItem = false;
    this.onMathML       = false;
    this.link           = false;
    this.inFrame        = false;
    this.hasBGImage     = false;
    this.isTextSelected = false;
    this.inDirList      = false;
    this.shouldDisplay  = true;

    // Initialize new menu.
    this.initMenu( xulMenu );
}

// Prototype for nsContextMenu "class."
nsContextMenu.prototype = {
    // onDestroy is a no-op at this point.
    onDestroy : function () {
    },
    // Initialize context menu.
    initMenu : function ( popup ) {
        // Save menu.
        this.menu = popup;

        // Get contextual info.
        this.setTarget( document.popupNode );
        
        this.isTextSelected = this.isTextSelection();

        this.initPopupURL();

        // Initialize (disable/remove) menu items.
        this.initItems();
    },
    initItems : function () {
        this.initOpenItems();
        this.initNavigationItems();
        this.initViewItems();
        this.initMiscItems();
        this.initSaveItems();
        this.initClipboardItems();
        this.initMetadataItems();
    },
    initOpenItems : function () {
        // this.showItem( "context-openlink", this.onSaveableLink || ( this.inDirList && this.onLink ) );
        this.showItem( "context-openlinkintab", this.onSaveableLink || ( this.inDirList && this.onLink ) );

        this.showItem( "context-sep-open", this.onSaveableLink || ( this.inDirList && this.onLink ) );
    },
    initNavigationItems : function () {
        // Back determined by canGoBack broadcaster.
        this.setItemAttrFromNode( "context-back", "disabled", "canGoBack" );

        // Forward determined by canGoForward broadcaster.
        this.setItemAttrFromNode( "context-forward", "disabled", "canGoForward" );
        
        this.showItem( "context-back", !( this.isTextSelected || this.onLink || this.onImage || this.onTextInput ) );
        this.showItem( "context-forward", !( this.isTextSelected || this.onLink || this.onImage || this.onTextInput ) );

        this.showItem( "context-reload", !( this.isTextSelected || this.onLink || this.onImage || this.onTextInput ) );
        
        this.showItem( "context-stop", !( this.isTextSelected || this.onLink || this.onImage || this.onTextInput ) );
        this.showItem( "context-sep-stop", !( this.isTextSelected || this.onLink || this.onImage || this.onTextInput ) );

        // XXX: Stop is determined in navigator.js; the canStop broadcaster is broken
        //this.setItemAttrFromNode( "context-stop", "disabled", "canStop" );
    },
    initSaveItems : function () {
        this.showItem( "context-savepage", !( this.inDirList || this.isTextSelected || this.onTextInput ) && !( this.onLink && this.onImage ) );

        // Save link depends on whether we're in a link.
        this.showItem( "context-savelink", this.onSaveableLink );

        // Save image depends on whether there is one.
        this.showItem( "context-saveimage", this.onLoadedImage );
        
        this.showItem( "context-sendimage", this.onImage );
    },
    initViewItems : function () {
        // View source is always OK, unless in directory listing.
        this.showItem( "context-viewpartialsource-selection", this.isTextSelected && !this.onTextInput );
        this.showItem( "context-viewpartialsource-mathml", this.onMathML && !this.isTextSelected );
        this.showItem( "context-viewsource", !( this.inDirList || this.onImage || this.isTextSelected || this.onLink || this.onTextInput ) );
        this.showItem( "context-viewinfo", !( this.inDirList || this.onImage || this.isTextSelected || this.onLink || this.onTextInput ) );

        this.showItem( "context-sep-properties", !( this.inDirList || this.isTextSelected || this.onTextInput ) );
        // Set As Wallpaper depends on whether an image was clicked on, and only works on Windows.
        var isWin = navigator.appVersion.indexOf("Windows") != -1;
        this.showItem( "context-setWallpaper", isWin && this.onLoadedImage );

        this.showItem( "context-sep-image", this.onImage );

        if( isWin && this.onLoadedImage )
            // Disable the Set As Wallpaper menu item if we're still trying to load the image
          this.setItemAttr( "context-setWallpaper", "disabled", (("complete" in this.target) && !this.target.complete) ? "true" : null );

        this.showItem( "context-fitimage", this.onStandaloneImage && _content.document.imageResizingEnabled );
        if ( this.onStandaloneImage && _content.document.imageResizingEnabled ) {
          this.setItemAttr( "context-fitimage", "disabled", _content.document.imageIsOverflowing ? null : "true");
          this.setItemAttr( "context-fitimage", "checked", _content.document.imageIsResized ? "true" : null);
        }

        // View Image depends on whether an image was clicked on.
        this.showItem( "context-viewimage", this.onImage && !this.onStandaloneImage);

        // View background image depends on whether there is one.
        this.showItem( "context-viewbgimage", !( this.inDirList || this.onImage || this.isTextSelected || this.onLink || this.onTextInput ) );
        this.showItem( "context-sep-viewbgimage", !( this.inDirList || this.onImage || this.isTextSelected || this.onLink || this.onTextInput ) );
        this.setItemAttr( "context-viewbgimage", "disabled", this.hasBGImage ? null : "true");
    },
    initMiscItems : function () {
        // Use "Bookmark This Link" if on a link.
        this.showItem( "context-bookmarkpage", !( this.isTextSelected || this.onTextInput ) );
        this.showItem( "context-bookmarklink", this.onLink && !this.onMailtoLink );
        this.showItem( "context-searchselect", this.isTextSelected && !this.onTextInput );
        this.showItem( "frame", this.inFrame );
        this.showItem( "frame-sep", this.inFrame );
        var blocking = true;
        if (this.popupURL)
          try {
            const PM = Components.classes["@mozilla.org/PopupWindowManager;1"]
                       .getService(Components.interfaces.nsIPopupWindowManager);
            blocking = PM.testPermission(this.popupURL) ==
                       Components.interfaces.nsIPopupWindowManager.DENY_POPUP;
          } catch (e) {
          }

        this.showItem( "popupwindow-reject", this.popupURL && !blocking);
        this.showItem( "popupwindow-allow", this.popupURL && blocking);
        this.showItem( "context-sep-popup", this.popupURL);
    },
    initClipboardItems : function () {

        // Copy depends on whether there is selected text.
        // Enabling this context menu item is now done through the global
        // command updating system
        // this.setItemAttr( "context-copy", "disabled", !this.isTextSelected() );

        goUpdateGlobalEditMenuItems();

        this.showItem( "context-undo", this.onTextInput );
        this.showItem( "context-redo", this.onTextInput );
        this.showItem( "context-sep-undo", this.onTextInput );
        this.showItem( "context-cut", this.onTextInput );
        this.showItem( "context-copy", this.isTextSelected || this.onTextInput);
        this.showItem( "context-paste", this.onTextInput );
        this.showItem( "context-delete", this.onTextInput );
        this.showItem( "context-sep-paste", this.onTextInput );
        this.showItem( "context-selectall", true );
        this.showItem( "context-sep-selectall", this.isTextSelected && !this.onTextInput );
        // In a text area there will be nothing after select all, so we don't want a sep
        // Otherwise, if there's text selected then there are extra menu items
        // (search for selection and view selection source), so we do want a sep

        // XXX dr
        // ------
        // nsDocumentViewer.cpp has code to determine whether we're
        // on a link or an image. we really ought to be using that...

        // Copy email link depends on whether we're on an email link.
        this.showItem( "context-copyemail", this.onMailtoLink );

        // Copy link location depends on whether we're on a link.
        this.showItem( "context-copylink", this.onLink );
        this.showItem( "context-sep-copylink", this.onLink );

        // Copy image location depends on whether we're on an image.
        this.showItem( "context-copyimage", this.onImage );
        this.showItem( "context-sep-copyimage", this.onImage );
    },
    initMetadataItems : function () {
        // Show if user clicked on something which has metadata.
        this.showItem( "context-metadata", this.onMetaDataItem );
    },
    // Set various context menu attributes based on the state of the world.
    setTarget : function ( node ) {
        const xulNS = "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul";
        if ( node.namespaceURI == xulNS ) {
          this.shouldDisplay = false;
          return;
        }
        // Initialize contextual info.
        this.onImage    = false;
        this.onLoadedImage = false;
        this.onStandaloneImage = false;
        this.onMetaDataItem = false;
        this.onTextInput = false;
        this.imageURL   = "";
        this.onLink     = false;
        this.onMathML   = false;
        this.inFrame    = false;
        this.hasBGImage = false;
        this.bgImageURL = "";

        // Remember the node that was clicked.
        this.target = node;