releases-comm-central/mail/modules/SummaryFrameManager.sys.mjs

106 строки
3.3 KiB
JavaScript

/* 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/. */
/**
* The SummaryFrameManager manages the source attribute of iframes which can
* be multi-purposed. For example, the thread/multimessage summary and the
* folder summary both use it. The SummaryFrameManager takes care of
* causing the content file to be reloaded as necessary, and manages event
* handlers, so that the right callback is called when the specified
* document is loaded.
*
* @param {HTMLIFrameElement} aFrame - The iframe that we're managing.
*/
export function SummaryFrameManager(aFrame) {
this.iframe = aFrame;
this.iframe.addEventListener(
"DOMContentLoaded",
this._onLoad.bind(this),
true
);
this.pendingCallback = null;
this.pendingOrLoadedUrl = this.iframe.docShell
? this.iframe.contentDocument.location.href
: "about:blank";
this.callback = null;
this.url = "";
}
SummaryFrameManager.prototype = {
/**
* Clear the summary frame.
*/
clear() {
this.loadAndCallback("about:blank");
},
/**
* Load the specified URL if necessary, and cause the specified callback to be
* called either when the document is loaded, or immediately if the document
* is already loaded.
*
* @param {string} aUrl - The URL to load.
* @param {function(boolean):void} aCallback - The callback to run when the
* URL has loaded; this function is passed a single boolean indicating if
* the URL was changed.
*/
loadAndCallback(aUrl, aCallback) {
this.url = aUrl;
if (this.pendingOrLoadedUrl != aUrl) {
// We're changing the document. Stash the callback that we want to call
// when it's done loading
this.pendingCallback = aCallback;
this.callback = null; // clear it
this.iframe.contentDocument.location.href = aUrl;
this.pendingOrLoadedUrl = aUrl;
} else if (!this.pendingCallback) {
// We're being called, but the document has been set already -- either
// we've already received the DOMContentLoaded event, in which case we can
// just call the callback directly, or we're still loading in which case
// we should just wait for the dom event handler, but update the callback.
this.callback = aCallback;
if (this.callback) {
this.callback(false);
}
} else {
this.pendingCallback = aCallback;
}
},
/**
* @param {Event} event
*/
_onLoad(event) {
try {
// Make sure we're responding to the summary frame being loaded, and not
// some subnode.
if (
event.target != this.iframe.contentDocument ||
this.pendingOrLoadedUrl == "about:blank"
) {
return;
}
if (event.target.ownerGlobal.location.href == "about:blank") {
return;
}
this.callback = this.pendingCallback;
this.pendingCallback = null;
if (
this.pendingOrLoadedUrl != this.iframe.contentDocument.location.href
) {
console.error(
"Please do not load stuff in the multimessage browser directly, " +
"use the SummaryFrameManager instead."
);
} else if (this.callback) {
this.callback(true);
}
} catch (e) {
console.error(e);
}
},
};