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/* 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
"use strict";
const {
setIgnoreLayoutChanges,
const {
CanvasFrameAnonymousContentHelper,
/**
* The ViewportSizeHighlighter is a class that displays the viewport
* width and height on a small overlay on the top right edge of the page
* while the rulers are turned on.
*/
class ViewportSizeHighlighter {
constructor(highlighterEnv) {
this.env = highlighterEnv;
this.markup = new CanvasFrameAnonymousContentHelper(
highlighterEnv,
this._buildMarkup.bind(this)
);
this.isReady = this.markup.initialize();
const { pageListenerTarget } = highlighterEnv;
pageListenerTarget.addEventListener("pagehide", this);
}
ID_CLASS_PREFIX = "viewport-size-highlighter-";
_buildMarkup() {
const prefix = this.ID_CLASS_PREFIX;
const container = this.markup.createNode({
attributes: { class: "highlighter-container" },
});
this.markup.createNode({
parent: container,
attributes: {
class: "viewport-infobar-container",
id: "viewport-infobar-container",
position: "top",
},
prefix,
});
return container;
}
handleEvent(event) {
switch (event.type) {
case "pagehide":
// If a page hide event is triggered for current window's highlighter, hide the
// highlighter.
if (event.target.defaultView === this.env.window) {
this.destroy();
}
break;
}
}
_update() {
const { window } = this.env;
setIgnoreLayoutChanges(true);
this.updateViewportInfobar();
setIgnoreLayoutChanges(false, window.document.documentElement);
this._rafID = window.requestAnimationFrame(() => this._update());
}
_cancelUpdate() {
if (this._rafID) {
this.env.window.cancelAnimationFrame(this._rafID);
this._rafID = 0;
}
}
updateViewportInfobar() {
const { window } = this.env;
const { innerHeight, innerWidth } = window;
const infobarId = this.ID_CLASS_PREFIX + "viewport-infobar-container";
const textContent = innerWidth + "px \u00D7 " + innerHeight + "px";
this.markup.getElement(infobarId).setTextContent(textContent);
}
destroy() {
this.hide();
const { pageListenerTarget } = this.env;
if (pageListenerTarget) {
pageListenerTarget.removeEventListener("pagehide", this);
}
this.markup.destroy();
EventEmitter.emit(this, "destroy");
}
show() {
this.markup.removeAttributeForElement(
this.ID_CLASS_PREFIX + "viewport-infobar-container",
"hidden"
);
this._update();
return true;
}
hide() {
this.markup.setAttributeForElement(
this.ID_CLASS_PREFIX + "viewport-infobar-container",
"hidden",
"true"
);
this._cancelUpdate();
}
}
exports.ViewportSizeHighlighter = ViewportSizeHighlighter;