Set preferences in the user branch and unset them on uninstall

Question

I created a firefox add-on with the following lib/main.js:

const {Cc,Ci} = require(\"chrome\");
var pref = Cc[\"@mozilla.org/preferences-service;1\"].getServ         


        

Answer 1

Here's how I did it just now:

function clearPrefBranch(aPrefBranchName) {                                     
  var defaultBranch = Services.prefs.getDefaultBranch(null);                    
  defaultBranch.deleteBranch(aPrefBranchName);                                  
}    

Then, just call clearPrefBranch with an argument of extensions.mypluginname (assuming you used the naming convention, and you should be able to delete all of your extension's installed preferences.

EDIT:

The code I used inside of my main.js file:

const {Cc,Ci,Cm,Cr,Cu} = require("chrome");                                     
Cu.import("resource://gre/modules/Services.jsm");  

exports.onUnload = function(aOptions, aCallbacks) {                             
  MyPlugin.shutdown();                                                           
};

function clearPrefBranch(aPrefBranchName) {                                     
  var defaultBranch = Services.prefs.getDefaultBranch(null);                    
  defaultBranch.deleteBranch(aPrefBranchName);                                  
}

var MyPlugin = {
  shutdown: function() {                                                      
    prefLoader.clearPrefBranch('extensions.oopstab');                         

  }
}; 

Answer 2

I solved the second part (uninstall) like this, that in my main.js I added this code at the end:

exports.onUnload = function(reason) {
    //called when add-on is 
    //    uninstalled
    //    disabled
    //    shutdown
    //    upgraded
    //    downgraded
    pref.clearUserPref("network.http.response.timeout");
};

That worked on disabling and uninstalling the add-on.