cocos creator 实现加载远程资源到本地缓存
在项目开发过程中有时候需要将远程连接的图片加载到本地存放，供以后使用，但是在cocos 官方文档里面没有详细的介绍存放到本地的方法，现在在这里讲述如何将远程资源加载到本地进行保存
首先新建一个对象类专门用来管理加载图片的类
ImageLoader.js
var md = require("./md5");
cc.Class({
extends: cc.Component,
statics : {
loadImage : function (url,callback){
cc.loader.load(url,function (err,tex) {
var spriteFrame = new cc.SpriteFrame(tex, cc.Rect(0, 0, tex.width, tex.height));
callback(spriteFrame);
});
},
imageLoadTool(url, callback){
var dirpath = jsb.fileUtils.getWritablePath() + 'customHeadImage/';
console.log("dirpath ->",dirpath);
let md5URL = md(url);
var filepath = dirpath + md5URL + '.jpg';
console.log("filepath ->",filepath);
function loadEnd(){
cc.loader.load(filepath, function(err, tex){
if( err ){
cc.error(err);
}else{
var spriteFrame = new cc.SpriteFrame(tex);
if( spriteFrame ){
spriteFrame.retain();
callback(spriteFrame);
}
}
});
}
if( jsb.fileUtils.isFileExist(filepath) ){
cc.log('Remote is find' + filepath);
loadEnd();
return;
}
var saveFile = function(data){
if( typeof data !== 'undefined' ){
if( !jsb.fileUtils.isDirectoryExist(dirpath) ){
jsb.fileUtils.createDirectory(dirpath);
}else{
console.log("路径exist");
}
// new Uint8Array(data) writeDataToFile writeStringToFile
if( jsb.fileUtils.writeDataToFile( new Uint8Array(data) , filepath) ){
cc.log('Remote write file succeed.');
loadEnd();
}else{
cc.log('Remote write file failed.');
}
}else{
cc.log('Remote download file failed.');
}
};
var xhr = new XMLHttpRequest();
xhr.onreadystatechange = function () {
cc.log("xhr.readyState " +xhr.readyState);
cc.log("xhr.status " +xhr.status);
if (xhr.readyState === 4 ) {
if(xhr.status === 200){
//responseType一定要在外面设置
// xhr.responseType = 'arraybuffer';
saveFile(xhr.response);
}else{
saveFile(null);
}
}
}.bind(this);
//responseType一定要在外面设置
xhr.responseType = 'arraybuffer';
xhr.open("GET", url, true);
xhr.send();
},
},
});这里的第一句的var md = require("md5"); 引用了md5.js
这里提供md5.js的源码直接下载即可：
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