" sessionstore状态读取"观察者不工作

时间:2012-02-12 21:01:35

标签: firefox firefox-addon observer-pattern

我目前正在制作一个firefox扩展程序,它允许您选择要在启动后重新打开的选项卡,而不是打开所有内容(它打开:sessionrestore页面)。我的JS代码如下所示:

编辑:使用工作版更新的代码

chrome.manifest用于

component {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} components/myextension.js
contract @example.com/MyExtension;1 {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}
category profile-after-change MyExtension @example.com/MyExtension;1

组件/ myextension.js

Components.utils.import("resource://gre/modules/XPCOMUtils.jsm");
const CI = Components.interfaces, CC = Components.classes, CR = Components.results;

// class declaration
function MyExtension () {}

MyExtension.prototype = {

    classDescription: "My Firefox Extension",
    classID:          Components.ID("{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}"),
    contractID:       "@example.com/MyExtension;1",
    QueryInterface: XPCOMUtils.generateQI([CI.nsIObserver]),

    // add to category manager
    _xpcom_categories: [{
        category: "profile-after-change"
    }],

    observe: function(aSubject, aTopic, aData) 
    {
        var obs = CC["@mozilla.org/observer-service;1"].getService(CI.nsIObserverService);

        switch (aTopic) 
        {
            case "profile-after-change":
                obs.addObserver(this, "sessionstore-state-read", false);
                break;
            case "sessionstore-state-read":
                aSubject.QueryInterface(CI.nsISupportsString);
                let newData = { windows: [{ tabs: [{ entries: [{
                  url: "about:sessionrestore",
                  formdata: { "#sessionData": aSubject.data }
                }] }] }] };
                aSubject.data = JSON.stringify(newData);
                break;
            default:
                throw Components.Exception("Unknown topic: " + aTopic);
        }
    }
};

if (XPCOMUtils.generateNSGetFactory)  
    var NSGetFactory = XPCOMUtils.generateNSGetFactory([EmbarrassedObserver]); 
else  
    var NSGetModule = XPCOMUtils.generateNSGetModule([EmbarrassedObserver]); 

它适用于sessionstore-state-write(注释行),但我想用sessionstore-state-read事件来做,因为我不想编辑它写入磁盘的内容。问题是,当我改变读取事件时,我的观察者停止工作。我的猜测是我注册了观察者太晚了(在会话被读取之后),所以我试图尽快注册它(当首次加载扩展时,注意窗口加载事件),但它仍然无法工作。知道如何让它运作吗?

1 个答案:

答案 0 :(得分:0)

您需要将扩展​​名编写为XPCOM组件,以侦听更改后的配置文件通知(允许扩展程序监听的first通知)。然后,您的组件将能够侦听会话存储状态读取通知。