分享个下载apk文件，并打开的js

/*  
 * 下载模块  
 */  
function loadapp(url,btnid,num){  
    mui('body').on('tap',btnid,function(){  
        var loadid = this.getAttribute('id');  
        sendloadid = loadid.slice(num);  
        var getvalue = document.getElementById(loadid).innerHTML;  
        var loaddata = {  
            config: {  
                id:sendloadid  
            },  
            fun_Success: function(data) {  
                console.log(JSON.stringify(data));  
                var geturl = data.data.down_a;  
                if(geturl==''){  
                    alert("暂无数据可供下载");  
                }else{  
                    createDownload(geturl,loadid);  
                }  
            }  
        };  
        if(getvalue=='下载'){  
            Fun_App.ExAjax(url, loaddata);  
        }  
        if(getvalue != '下载'){  
            document.getElementById(loadid).addEventListener('tap',function(){  
                document.getElementById(loadid).innerHTML ="暂停";  
                pauseDownload();  
            });  
        }  
        if(getvalue =='暂停'){  
            document.getElementById(loadid).addEventListener('tap',function(){  
                resumeDownload();  
            });  
        }  
    });  
}  

/*  
 * 创建下载任务  
 */  
function createDownload(url,loadid) {  
    dtask = plus.downloader.createDownload(url);  
    dtask.addEventListener( "statechanged", function(download,status){  
        var fimename = download.getFileName().slice(11).replace('.apk','');  
        if ( download.state == 4 && status == 200 ) {  
            document.getElementById(loadid).innerHTML = "下载";  
            plus.nativeUI.confirm( "下载已完成，是否安装？", function(e){  
                if(e.index==0){  
                    openFile(download.getFileName());  
                }else{  
                    del();  
                }  
            }, fimename, ["确定","取消"] );  
        }else{  
            var progress = download.downloadedSize/download.totalSize*100;  
            progress = parseInt(progress.toFixed(2));  
            if(isNaN(progress)){  
                document.getElementById(loadid).innerHTML = "下载";  
            }else if(progress == 100){  
                del();  
                document.getElementById(loadid).innerHTML = "下载";  
            }else{  
                document.getElementById(loadid).innerHTML = progress + '%';  
            }  
        }  
    }, false );  
    dtask.start();   
}  

/*  
 * 暂停下载任务  
 */  
function pauseDownload() {  
    dtask.pause();  
}  
/*  
 * 恢复下载任务  
 */  
function resumeDownload() {  
    dtask.resume();  
}  
/*  
 * 取消下载  
 */  
function del(){  
    plus.downloader.clear();  
}  
/*  
 * 打开文件操作  
 */  
function openFile(fileName) {  
    plus.runtime.openFile(fileName);  
}