preloadjs实现网页资源预加载

      

<!doctype html>
<html lang="zh">
<head>
    <title>PreloadJS的基础使用</title>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1"> 
    <style>
    </style>
    <script src="~/Scripts/jquery-1.8.2.min.js"></script>
</head>
<body>
    <canvas id="myCanvas" width="350" height="420"></canvas>
    <img id="myimg" src="" />
    <script src="../Scripts/jquery-1.8.2.min.js"></script>
    <script src="http://cdn.gbtags.com/EaselJS/0.7.1/easeljs.min.js"></script>
    <script src="http://cdn.gbtags.com/PreloadJS/0.4.1/preloadjs.min.js"></script>
    <script>

        var canvas = document.getElementById("myCanvas");
        var stage = new createjs.Stage(canvas);

        var manifest;
        var preload;
        var progressText = new createjs.Text("", "20px Arial", "#dd4814");
        progressText.x = 125 - progressText.getMeasuredWidth() / 2;
        progressText.y = 20;
        stage.addChild(progressText);
        stage.update();

        //定义相关JSON格式文件列表
        function setupManifest() {
            manifest = [{
                src: "/images/test.png",
                id: "easeljs"
            }, {
                src: "http://www.gbtags.com/gb/networks/uploadimgthumb/4d8f3f13-89c0-455c-95f3-ba5120c2f123.jpg",
                id: "logo"
            }, {
                src: "http://www.gbtags.com/tutorials/html5-tutorial/html5-demos/assets/song.ogg",
                id: "audiofile"
            }

            ];
            for (var i = 1; i <= 25; i++)
                manifest.push({ src: "/images/"+i+".png" })
        }

        //开始预加载
        function startPreload() {
            preload = new createjs.LoadQueue(true);
            //注意加载音频文件需要调用如下代码行
            preload.installPlugin(createjs.Sound);
            preload.on("fileload", handleFileLoad);
            preload.on("progress", handleFileProgress);
            preload.on("complete", loadComplete);
            preload.on("error", loadError);
            preload.loadManifest(manifest);

        }

        //处理单个文件加载
        function handleFileLoad(event) {
            console.log("文件类型: " + event.item.type);
            if (event.item.id == "logo") {
                console.log("logo图片已成功加载");
            }
        }

        //处理加载错误：大家可以修改成错误的文件地址，可在控制台看到此方法调用
        function loadError(evt) {
            console.log("加载出错！", evt.text);
        }

        //已加载完毕进度
        function handleFileProgress(event) {
            progressText.text = "已加载 " + (preload.progress * 100 | 0) + " %";
            stage.update();
        }

        //全度资源加载完毕
        function loadComplete(event) {
            console.log("已加载完毕全部资源");
        }
        setupManifest();
        startPreload();
    </script>
</body>
</html>

效果:

 

posted on 2018-04-11 09:25  花生哒哒  阅读(4313)  评论(0)  编辑  收藏  举报

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