PC World Komputer 2010 April/PCWorld0410.iso/pluginy Firefox/201/201.xpi/modules/preferences.jsm

Text File | 2010-01-11 | 4KB | 209 lines

/* You may find the license in the LICENSE file */

const EXPORTED_SYMBOLS = [
    'get',
    'getExt',
    'set',
    'setExt',
    'hasUserValue',
    'hasUserValueExt',
    'getChildren',
    'getChildrenExt',
    'reset',
    'resetExt',
    'resetBranch',
    'resetBranchExt',
    'resetAllExt',
    'addObserver',
    'removeObserver',
    'makeObserver'
];

const EXT = 'extensions.dta.';

const Cc = Components.classes;
const Ci = Components.interfaces;
const nsIPrefBranch = Ci.nsIPrefBranch;
const nsIPrefBranch2 = Ci.nsIPrefBranch2;

const PREF_STRING = nsIPrefBranch.PREF_STRING;
const PREF_INT = nsIPrefBranch.PREF_INT;
const PREF_BOOL = nsIPrefBranch.PREF_BOOL;

const SupportsString = Components.Constructor('@mozilla.org/supports-string;1', 'nsISupportsString');

const prefs = Cc['@mozilla.org/preferences-service;1'].getService(Ci.nsIPrefBranch);

function get(key, defaultValue){
    try {
        let rv;
        switch (prefs.getPrefType(key)) {
            case PREF_INT:
                rv = prefs.getIntPref(key);
                break;
            case PREF_BOOL:
                rv = prefs.getBoolPref(key);
                break;
            default:
                rv = getMultiByte(key);
                break;
        }
        if (rv != undefined) {
            return rv;
        }
    }
    catch (ex) {
        // no-op
    }

    return defaultValue;
}

function getExt(key, defaultValue) {
        return get(EXT + key, defaultValue);
}

function set(key, value){
    if (typeof value == 'number' || value instanceof Number) {
        return prefs.setIntPref(key, value);
    }
    if (typeof value == 'boolean' || value instanceof Boolean) {
        return prefs.setBoolPref(key, value);
    }
    return setMultiByte(key, value);
}

function setExt(key, value){
    return set(EXT + key, value);
}

function getMultiByte(key, defaultValue){
    try {
        return prefs.getComplexValue(key, Ci.nsISupportsString).data;
    }
    catch (ex) {
        // no-op
    }
    return defaultValue;
}

function setMultiByte(key, value) {
    let str = new SupportsString();
    str.data = value.toString();
    prefs.setComplexValue(key, Ci.nsISupportsString, str);
}

function hasUserValue(key) {
    try {
        return prefs.prefHasUserValue(key);
    }
    catch (ex) {
        // no-op
    }
    return false;
}

function hasUserValueExt(key) {
    return hasUserValue(EXT + key);
}

function getChildren(key) {
    return prefs.getChildList(key, {});
}

function getChildrenExt(key) {
    return getChildren(EXT + key);
}

function reset(key) {
    try {
        return prefs.clearUserPref(key);
    }
    catch (ex) {
        // no-op
    }
    return false;
}


function resetExt(key) {
    if (key.search(new RegExp('/^' + EXT + '/')) != 0) {
        key = EXT + key;
    }
    return reset(key);
}

function resetBranch(branch) {
    try {
        prefs.resetBranch(branch);
    }
    catch (ex) {
        // BEWARE: not yet implemented in XPCOM 1.8/trunk.
        let children = prefs.getChildList(branch, {});
        for each (let key in children) {
            reset(key);
        }
    }
}

function resetBranchExt(branch) {
    resetBranch(EXT + branch);
}

function resetAllExt() {
    resetBranchExt('');
}

function addObserver(branch, obj) {
    makeObserver(obj);
    prefs.QueryInterface(nsIPrefBranch2).addObserver(branch, obj, true);
}

function removeObserver(branch, obj) {
    prefs.QueryInterface(nsIPrefBranch2).removeObserver(branch, obj);
}

function makeObserver(obj) {
    try {
        if (
            obj.QueryInterface(Ci.nsISupportsWeakReference)
            && obj.QueryInterface(Ci.nsIObserver)
        ) {
            return;
        }
    }
    catch (ex) {
        // fall-through
    }
    let __QueryInterface = obj.QueryInterface;
    obj.QueryInterface = function(iid) {
        try {
            if (
                iid.equals(Components.interfaces.nsISupports)
                || iid.equals(Components.interfaces.nsISupportsWeakReference)
                || iid.equals(Components.interfaces.nsIWeakReference)
                || iid.equals(Components.interfaces.nsIObserver)
            ) {
                return obj;
            }
            if (__QueryInterface) {
                debug("calling original: " + iid);
                return __QueryInterface.call(this, iid);
            }
            throw Components.results.NS_ERROR_NO_INTERFACE;
        }
        catch (ex) {
            debug("requested interface not available: " + iid);
            throw ex;
        }
    };
    // nsiWeakReference
    obj.QueryReferent = function(iid) {
        return obj.QueryInterface(iid);
    };
    // nsiSupportsWeakReference
    obj.GetWeakReference = function() {
        return obj;
    };
}