tv_xiaoyouxi/games/rocket/src/MyLoaderScene.js

/**
 * Created by Will on 2014/10/16.
 */
var MyLoaderScene = cc.Scene.extend({
    _interval : null,
    _length : 0,
    _count : 0,
    _label : null,
    _className:"MyLoaderScene",
    init : function(){
        var self = this;

        // bg
        var bgLayer = self._bgLayer = cc.LayerColor.create(cc.color(255, 255, 255));
        bgLayer.setPosition(cc.visibleRect.bottomLeft);
        self.addChild(bgLayer, 0);

        //loading percent
//        var label = self._label = cc.LabelTTF.create("玩命加载中... 0%", "Arial", 24);
//        label.setPosition(cc.pAdd(cc.visibleRect.center, cc.p(0, 0)));
//        label.setColor(cc.color(180, 180, 180));
//        bgLayer.addChild(this._label, 10);
        var jdt1 = self._jdt1 = new cc.Sprite(res.a_jdt1);
        jdt1.setPosition(cc.winSize.width/2,cc.winSize.height/2);
        jdt1.scale = 0.5;
//        jdt.scaleY = 0.3;
//        jdt.scaleX = 0.02;
        bgLayer.addChild(this._jdt1, 10);

        var jdt = self._jdt = new cc.Sprite(res.a_jdt);
        jdt.setPosition(cc.winSize.width/2 - 70,cc.winSize.height/2-5);
        jdt.anchorX = 0;
        jdt.anchorY = 0;
        jdt.scale = 0.005;
//        jdt.scaleY = 0.3;
//        jdt.scaleX = 0.02;
        bgLayer.addChild(this._jdt, 10);


        var img = self._img = new cc.Sprite(res.a_loading);
        img.setPosition(cc.winSize.width/2,cc.winSize.height/2);
        img.scale = cc.winSize.height/960;
        bgLayer.addChild(this._img, 1);
        return true;
    },

    _initStage: function (img, centerPos) {
        var self = this;
        var texture2d = self._texture2d = new cc.Texture2D();
        texture2d.initWithElement(img);
        texture2d.handleLoadedTexture();
        var logo = self._logo = cc.Sprite.create(texture2d);
        logo.setScale(cc.contentScaleFactor());
        logo.x = centerPos.x;
        logo.y = centerPos.y;
        self._bgLayer.addChild(logo, 10);
    },

    onEnter: function () {
        var self = this;
        cc.Node.prototype.onEnter.call(self);
        self.schedule(self._startLoading, 0.3);
    },

    onExit: function () {
        cc.Node.prototype.onExit.call(this);
        this._jdt.scale = 0.02;
    },

    /**
     * init with resources
     * @param {Array} resources
     * @param {Function|String} cb
     */
    initWithResources: function (resources, cb) {
        if(typeof resources == "string") resources = [resources];
        this.resources = resources || [];
        this.cb = cb;
    },

    _startLoading: function () {
        var self = this;
        self.unschedule(self._startLoading);
        var res = self.resources;
        self._length = res.length;
        self._count = 0;
        cc.loader.load(res, function(result, count){ self._count = count; }, function(){
            if(self.cb)
                self.cb();
        });
        self.schedule(self._updatePercent);
    },

    _updatePercent: function () {
        var self = this;
        var count = self._count;
        var length = self._length;
        var percent = (count / length * 100) | 0;
        percent = Math.min(percent, 100);
        self._jdt.scale = 0.5*percent/100;
        if(count >= length) self.unschedule(self._updatePercent);
    }
});
MyLoaderScene.preload = function(resources, cb){
    var _myLoaderScene = null;
    if(!_myLoaderScene) {
        _myLoaderScene = new MyLoaderScene();
        _myLoaderScene.init();
    }
    _myLoaderScene.initWithResources(resources, cb);

    cc.director.runScene(_myLoaderScene);
    return _myLoaderScene;
};