这是我的问题.
我正试图通过Asynctask使用下载管理器意图从我的服务器下载文件.
在asinctask类的doInBackground中,我调用了下载管理器intent,doinBackground将在下载完成时返回布尔值(成功或失败).
这是我的代码
我正试图通过Asynctask使用下载管理器意图从我的服务器下载文件.
在asinctask类的doInBackground中,我调用了下载管理器intent,doinBackground将在下载完成时返回布尔值(成功或失败).
这是我的代码
protected Boolean doInBackground(String... f_url) {
boolean flag = true;
boolean downloading =true;
try{
DownloadManager mManager = (DownloadManager) getSystemService(Context.DOWNLOAD_SERVICE);
Request mRqRequest = new Request(
Uri.parse("http://"+model.getDownloadURL()));
long idDownLoad=mManager.enqueue(mRqRequest);
DownloadManager.Query query = null;
query = new DownloadManager.Query();
Cursor c = null;
if(query!=null) {
query.setFilterByStatus(DownloadManager.STATUS_Failed|DownloadManager.STATUS_PAUSED|DownloadManager.STATUS_SUCCESSFUL|
DownloadManager.STATUS_RUNNING|DownloadManager.STATUS_PENDING);
} else {
return flag;
}
c = mManager.query(query);
if(c.moveToFirst()) {
int status =c.getInt(c.getColumnIndex(DownloadManager.COLUMN_STATUS));
while (downloading)
{ Log.i ("FLAG","Downloading");
if (status==DownloadManager.STATUS_SUCCESSFUL)
{ Log.i ("FLAG","done");
downloading = false;
flag=true;
break;
}
if (status==DownloadManager.STATUS_Failed)
{Log.i ("FLAG","Fail");
downloading = false;
flag=false;
break;
}
c.moveToFirst();
}
}
return flag;
}
catch (Exception e)
{
flag = false;
return flag;
}
}
但DownloadManager状态永远不会跳转到DownloadManager.STATUS_SUCCESSFUL或DownloadManager.STATUS_Failed.
对我有什么帮助吗？
解决方法
您必须重新查询下载管理器.即使数据发生变化,光标也保持不变.试试这样：
protected Boolean doInBackground(String... f_url) {
boolean flag = true;
boolean downloading =true;
try{
DownloadManager mManager = (DownloadManager) getSystemService(Context.DOWNLOAD_SERVICE);
Request mRqRequest = new Request(
Uri.parse("http://"+model.getDownloadURL()));
long idDownLoad=mManager.enqueue(mRqRequest);
DownloadManager.Query query = null;
query = new DownloadManager.Query();
Cursor c = null;
if(query!=null) {
query.setFilterByStatus(DownloadManager.STATUS_Failed|DownloadManager.STATUS_PAUSED|DownloadManager.STATUS_SUCCESSFUL|DownloadManager.STATUS_RUNNING|DownloadManager.STATUS_PENDING);
} else {
return flag;
}
while (downloading) {
c = mManager.query(query);
if(c.moveToFirst()) {
Log.i ("FLAG","Downloading");
int status =c.getInt(c.getColumnIndex(DownloadManager.COLUMN_STATUS));
if (status==DownloadManager.STATUS_SUCCESSFUL) {
Log.i ("FLAG","done");
downloading = false;
flag=true;
break;
}
if (status==DownloadManager.STATUS_Failed) {
Log.i ("FLAG","Fail");
downloading = false;
flag=false;
break;
}
}
}
return flag;
}catch (Exception e) {
flag = false;
return flag;
}
}
