Cocos2d-JS开发中的一些小技巧

1、获取URL中的请求参数的值----此方法接收参数名

function getQueryString(name) {
    var reg = new RegExp("(^|&)" + name + "=([^&]*)(&|$)", "i");
    var r = window.location.search.substr(1).match(reg);
    if (r != null) return decodeURIComponent(r[2]);
    return null;
};

2、底图上添加文字---适用于按钮Sprite

var MyButtonSprite = cc.Sprite.extend({
    ctor: function (fileName, title, fontName, fontSize) {
        this._super(fileName);

        var titleLabel = new cc.LabelTTF(title, fontName, fontSize);
        this.addChild(titleLabel);
        titleLabel.x = this.getContentSize().width / 2;
        titleLabel.y = this.getContentSize().height / 2;
    }
});

3、远程图片加载

loadImgFromUrl: function (target, imgUrl, p, tag) {
        if(!imgUrl)return;
        var self = target;
        var loadCb = function(err, img){
            cc.textureCache.addImage(imgUrl);
            var texture2d = new cc.Texture2D();
            texture2d.initWithElement(img);
            texture2d.handleLoadedTexture();
            var sp = new cc.Sprite();
            sp.initWithTexture(texture2d);
            self.addChild(sp);
            sp.x = p.x;
            sp.y = p.y;
            sp.tag = tag;
        };
        cc.loader.loadImg(imgUrl, {isCrossOrigin : false }, loadCb);
    },

4、XMLHttpRequest

var sendRequest = function(url, params, isPost, callback, errorcallback){
    if(url == null || url == '')
        return;

    var xhr = cc.loader.getXMLHttpRequest();
    if(isPost){
        xhr.open("POST",url);
    }else{
        xhr.open("GET",url);
    }
    xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
    xhr.onreadystatechange = function () {
        if(xhr.readyState == 4 && xhr.status == 200){
            var response = xhr.responseText;
            if(callback)
                callback(response);
        }else if(xhr.readyState == 4 && xhr.status != 200){
            var response = xhr.responseText;
            if(errorcallback)
                errorcallback(response);
        }
    };

    if(params == null || params == ""){
        xhr.send();
    }else{
        xhr.send(params);
    }
};

5、JSON解析以及上述第4条的回调方法

var callback = function (response) {
        var jsonData = JSON.parse(response);
        var data = jsonData["users"];
        if(data){
            alert(data["name"]);
            // todo something
        }
    };

6、自定义Loading界面

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(32, 32, 32, 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);
        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);
        var tmpStr = "玩命加载中... 0%";
        this._label.setString(tmpStr);
    },

    /**
     * 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._label.setString("玩命加载中... " + percent + "%");
        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;
};

7、网页跳转

window.location.href = "http://www.baidu.com"

8、关于进入游戏时黑屏时间较长的处理方法

1）

<body style="padding:0; margin: 0; background: #000;">

删除index.html中<body>标签的样式background: #000;

2）按照自己需要添加编译模块 修改project.json如

"modules" : ["core", "actions","shape-nodes", "labels","menus","transitions","physics","chipmunk","gui"],

原文链接:http://cn.cocos2d-x.org/tutorial/show?id=1431