/* #ifdef 0 * ***** 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 Content Preferences (cpref). * * The Initial Developer of the Original Code is Mozilla. * Portions created by the Initial Developer are Copyright (C) 2006 * the Initial Developer. All Rights Reserved. * * Contributor(s): * Myk Melez * * 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 * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** #endif */ // From nsMouseScrollEvent::kIsHorizontal const MOUSE_SCROLL_IS_HORIZONTAL = 1 << 2; // Not sure where this comes from. It's one of the possible values // for the mousewheel.* preferences. const MOUSE_SCROLL_TEXTSIZE = 3; /** * Controls the "text zoom" setting and its site-specific preferences. */ var TextZoom = { //**************************************************************************// // Name & Values // The name of the setting. Identifies the setting in the prefs database. name: "browser.content.text-zoom", // The global value (if any) for the setting. Retrieved from the prefs // database when this handler gets initialized, then updated as it changes. // If there is no global value, then this should be undefined. globalValue: undefined, // From viewZoomOverlay.js minValue: 1, maxValue: 2000, defaultValue: 100, //**************************************************************************// // Convenience Getters __zoomManager: null, get _zoomManager() { if (!this.__zoomManager) this.__zoomManager = ZoomManager.prototype.getInstance(); return this.__zoomManager; }, // Content Pref Service __cps: null, get _cps() { if (!this.__cps) this.__cps = Cc["@mozilla.org/content-pref/service;1"]. getService(Ci.nsIContentPrefService); return this.__cps; }, // Pref Branch __prefBranch: null, get _prefBranch() { if (!this.__prefBranch) this.__prefBranch = Cc["@mozilla.org/preferences-service;1"]. getService(Ci.nsIPrefBranch); return this.__prefBranch; }, //**************************************************************************// // nsISupports // We can't use the Ci shortcut here because it isn't defined yet. interfaces: [Components.interfaces.nsIDOMEventListener, Components.interfaces.nsIContentPrefObserver, Components.interfaces.nsISupports], QueryInterface: function TextZoom_QueryInterface(aIID) { if (!this.interfaces.some( function(v) { return aIID.equals(v) } )) throw Cr.NS_ERROR_NO_INTERFACE; return this; }, //**************************************************************************// // Initialization & Destruction init: function TextZoom_init() { // Listen for scrollwheel events so we can save scrollwheel-based changes. window.addEventListener("DOMMouseScroll", this, false); // Register ourselves with the service so we know when our pref changes. this._cps.addObserver(this.name, this); // Register ourselves with the sink so we know when the location changes. var globalValue = ContentPrefSink.addObserver(this.name, this); this.globalValue = this._ensureValid(globalValue); // Set the initial value of the setting. this._applyPrefToSetting(); }, destroy: function TextZoom_destroy() { ContentPrefSink.removeObserver(this.name, this); this._cps.removeObserver(this.name, this); window.removeEventListener("DOMMouseScroll", this, false); // Delete references to XPCOM components to make sure we don't leak them // (although we haven't observed leakage in tests). for (var i in this) { try { this[i] = null } // Ignore "setting a property that has only a getter" exceptions. catch(ex) {} } }, //**************************************************************************// // Event Handlers // nsIDOMEventListener handleEvent: function TextZoom_handleEvent(event) { // The only events we handle are DOMMouseScroll events. this._handleMouseScrolled(event); }, _handleMouseScrolled: function TextZoom__handleMouseScrolled(event) { // Construct the "mousewheel action" pref key corresponding to this event. // Based on nsEventStateManager::GetBasePrefKeyForMouseWheel. var pref = "mousewheel"; if (event.scrollFlags & MOUSE_SCROLL_IS_HORIZONTAL) pref += ".horizscroll"; if (event.shiftKey) pref += ".withshiftkey"; else if (event.ctrlKey) pref += ".withcontrolkey"; else if (event.altKey) pref += ".withaltkey"; else if (event.metaKey) pref += ".withmetakey"; else pref += ".withnokey"; pref += ".action"; // Don't do anything if this isn't a "change text size" scroll event. if (this._getAppPref(pref, null) != MOUSE_SCROLL_TEXTSIZE) return; // XXX Lazily cache all the possible action prefs so we don't have to get // them anew from the pref service for every scroll event? We'd have to // make sure to observe them so we can update the cache when they change. // We have to call _applySettingToPref in a timeout because we handle // the event before the event state manager has a chance to apply the zoom // during nsEventStateManager::PostHandleEvent. window.setTimeout(function() { TextZoom._applySettingToPref() }, 0); }, // nsIContentPrefObserver onContentPrefSet: function TextZoom_onContentPrefSet(aGroup, aName, aValue) { if (aGroup == this._cps.grouper.group(gBrowser.currentURI)) this._applyPrefToSetting(aValue); else if (aGroup == null) { this.globalValue = this._ensureValid(aValue); // If the current page doesn't have a site-specific preference, // then its zoom should be set to the new global preference now that // the global preference has changed. if (!this._cps.hasPref(gBrowser.currentURI, this.name)) this._applyPrefToSetting(); } }, onContentPrefRemoved: function TextZoom_onContentPrefRemoved(aGroup, aName) { if (aGroup == this._cps.grouper.group(gBrowser.currentURI)) this._applyPrefToSetting(); else if (aGroup == null) { this.globalValue = undefined; // If the current page doesn't have a site-specific preference, // then its zoom should be set to the default preference now that // the global preference has changed. if (!this._cps.hasPref(gBrowser.currentURI, this.name)) this._applyPrefToSetting(); } }, // ContentPrefSink observer onLocationChanged: function TextZoom_onLocationChanged(aURI, aName, aValue) { this._applyPrefToSetting(aValue); }, //**************************************************************************// // Setting & Pref Manipulation reduce: function TextZoom_reduce() { this._zoomManager.reduce(); this._applySettingToPref(); }, enlarge: function TextZoom_enlarge() { this._zoomManager.enlarge(); this._applySettingToPref(); }, reset: function TextZoom_reset() { if (typeof this.globalValue != "undefined") this._zoomManager.textZoom = this.globalValue; else this._zoomManager.reset(); this._removePref(); }, /** * Set the text zoom for the current tab. * * Per DocumentViewerImpl::SetTextZoom in nsDocumentViewer.cpp, it looks * like we can set the zoom to its current value without significant impact * on performance, as the setting is only applied if it differs from the * current setting. * * And perhaps we should always set the zoom even if it were to incur * a performance penalty, since SetTextZoom claims that child documents * may have a different zoom under unusual circumstances, and it implies * that those child zooms should get updated when the parent zoom gets set. * * So when we apply new zoom values to the browser, we simply set the zoom. * We don't check first to see if the new value is the same as the current * one. **/ _applyPrefToSetting: function TextZoom__applyPrefToSetting(aValue) { // Bug 375918 means this will sometimes throw, so we catch it // and don't do anything in those cases. try { if (typeof aValue != "undefined") this._zoomManager.textZoom = this._ensureValid(aValue); else if (typeof this.globalValue != "undefined") this._zoomManager.textZoom = this.globalValue; else this._zoomManager.reset(); } catch(ex) {} }, _applySettingToPref: function TextZoom__applySettingToPref() { var textZoom = this._zoomManager.textZoom; this._cps.setPref(gBrowser.currentURI, this.name, textZoom); }, _removePref: function TextZoom__removePref() { this._cps.removePref(gBrowser.currentURI, this.name); }, //**************************************************************************// // Utilities _ensureValid: function TextZoom__ensureValid(aValue) { if (isNaN(aValue)) return this.defaultValue; if (aValue < this.minValue) return this.minValue; if (aValue > this.maxValue) return this.maxValue; return aValue; }, /** * Get a value from a pref or a default value if the pref doesn't exist. * * @param aPrefName * @param aDefaultValue * @returns the pref's value or the default (if it is missing) */ _getAppPref: function TextZoom__getAppPref(aPrefName, aDefaultValue) { try { switch (this._prefBranch.getPrefType(aPrefName)) { case this._prefBranch.PREF_STRING: return this._prefBranch.getCharPref(aPrefName); case this._prefBranch.PREF_BOOL: return this._prefBranch.getBoolPref(aPrefName); case this._prefBranch.PREF_INT: return this._prefBranch.getIntPref(aPrefName); } } catch (ex) { /* return the default value */ } return aDefaultValue; } };