gecko-dev/toolkit/actors/ZoomChild.jsm
2019-06-26 18:16:42 +00:00

89 lines
2.2 KiB
JavaScript

/* vim: set ts=2 sw=2 sts=2 et tw=80: */
/* 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/. */
"use strict";
var EXPORTED_SYMBOLS = ["ZoomChild"];
class ZoomChild extends JSWindowActorChild {
constructor() {
super();
this._cache = {
fullZoom: NaN,
textZoom: NaN,
};
}
get fullZoom() {
return this._cache.fullZoom;
}
get textZoom() {
return this._cache.textZoom;
}
set fullZoom(value) {
this._cache.fullZoom = value;
this._markupViewer.fullZoom = value;
}
set textZoom(value) {
this._cache.textZoom = value;
this._markupViewer.textZoom = value;
}
refreshFullZoom() {
return this._refreshZoomValue("fullZoom");
}
refreshTextZoom() {
return this._refreshZoomValue("textZoom");
}
/**
* Retrieves specified zoom property value from markupViewer and refreshes
* cache if needed.
* @param valueName Either 'fullZoom' or 'textZoom'.
* @returns Returns true if cached value was actually refreshed.
* @private
*/
_refreshZoomValue(valueName) {
let actualZoomValue = this._markupViewer[valueName];
// Round to remove any floating-point error.
actualZoomValue = Number(actualZoomValue.toFixed(2));
if (actualZoomValue != this._cache[valueName]) {
this._cache[valueName] = actualZoomValue;
return true;
}
return false;
}
get _markupViewer() {
return this.docShell.contentViewer;
}
receiveMessage(message) {
if (message.name == "FullZoom") {
this.fullZoom = message.data.value;
} else if (message.name == "TextZoom") {
this.textZoom = message.data.value;
}
}
handleEvent(event) {
if (event.type == "FullZoomChange") {
if (this.refreshFullZoom()) {
this.sendAsyncMessage("FullZoomChange", { value: this.fullZoom });
}
} else if (event.type == "TextZoomChange") {
if (this.refreshTextZoom()) {
this.sendAsyncMessage("TextZoomChange", { value: this.textZoom });
}
} else if (event.type == "ZoomChangeUsingMouseWheel") {
this.sendAsyncMessage("ZoomChangeUsingMouseWheel", {});
}
}
}