我正在给我的用户下载文件的机会。
有时这个文件非常大,我在下载时正在实现ProgressDialog
。
好吧,如果用户点击后退,我想取消AsyncTask
并关闭连接:
@Override
protected void onPreExecute() {
super.onPreExecute();
pd = new ProgressDialog(main);
pd.setMessage("Downloading PDF...");
pd.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
pd.setCancelable(true);
pd.setCanceledOnTouchOutside(false);
pd.setOnCancelListener(new OnCancelListener() {
public void onCancel(DialogInterface var1) {
cancel(true);
if(httppost != null) {
httppost.abort();
}
try {
if (downloader != null) {
downloader.closeConnection();
}
} catch (Exception e) {
e.printStackTrace();
}
}
});
pd.setIndeterminate(false);
pd.show();
}
我的downloader
是一个自己的类,closeConnection的功能是:
public void closeConnection() { // urlConnection is a HttpURLConnection.
if (urlConnection!=null)
try {
urlConnection.getInputStream().close();
} catch (Exception e) {
e.printStackTrace();
}
}
但是当我这样做时,我得到了:
06-25 21:13:03.169: W/InputEventReceiver(18144): Attempted to finish an input event but the input event receiver has already been disposed.
06-25 21:13:03.179: W/System.err(18144): android.os.NetworkOnMainThreadException
06-25 21:13:03.179: W/System.err(18144): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1156)
06-25 21:13:03.179: W/System.err(18144): at libcore.io.BlockGuardOs.recvfrom(BlockGuardOs.java:163)
06-25 21:13:03.179: W/System.err(18144): at libcore.io.IoBridge.recvfrom(IoBridge.java:506)
06-25 21:13:03.179: W/System.err(18144): at java.net.PlainSocketImpl.read(PlainSocketImpl.java:489)
06-25 21:13:03.179: W/System.err(18144): at java.net.PlainSocketImpl.access$000(PlainSocketImpl.java:46)
06-25 21:13:03.179: W/System.err(18144): at java.net.PlainSocketImpl$PlainSocketInputStream.read(PlainSocketImpl.java:241)
06-25 21:13:03.179: W/System.err(18144): at java.io.BufferedInputStream.read(BufferedInputStream.java:283)
06-25 21:13:03.179: W/System.err(18144): at com.android.okhttp.internal.http.HttpTransport$FixedLengthInputStream.read(HttpTransport.java:386)
06-25 21:13:03.179: W/System.err(18144): at libcore.io.Streams.skipByReading(Streams.java:158)
06-25 21:13:03.179: W/System.err(18144): at java.io.InputStream.skip(InputStream.java:227)
06-25 21:13:03.179: W/System.err(18144): at com.android.okhttp.internal.Util.skipAll(Util.java:249)
06-25 21:13:03.189: W/System.err(18144): at com.android.okhttp.internal.http.HttpTransport.discardStream(HttpTransport.java:190)
06-25 21:13:03.189: W/System.err(18144): at com.android.okhttp.internal.http.HttpTransport.access$200(HttpTransport.java:32)
06-25 21:13:03.189: W/System.err(18144): at com.android.okhttp.internal.http.HttpTransport$FixedLengthInputStream.close(HttpTransport.java:408)
06-25 21:13:03.189: W/System.err(18144): at farma.r.resources.Downloader.closeConnection(Downloader.java:23)
06-25 21:13:03.189: W/System.err(18144): at farma.r.free.fragments.promo.mainPromoFragment$ChiamataPOSTPDF$1.onCancel(mainPromoFragment.java:292)
06-25 21:13:03.189: W/System.err(18144): at android.app.Dialog$ListenersHandler.handleMessage(Dialog.java:1253)
06-25 21:13:03.189: W/System.err(18144): at android.os.Handler.dispatchMessage(Handler.java:102)
06-25 21:13:03.189: W/System.err(18144): at android.os.Looper.loop(Looper.java:157)
06-25 21:13:03.189: W/System.err(18144): at android.app.ActivityThread.main(ActivityThread.java:5356)
06-25 21:13:03.189: W/System.err(18144): at java.lang.reflect.Method.invokeNative(Native Method)
06-25 21:13:03.189: W/System.err(18144): at java.lang.reflect.Method.invoke(Method.java:515)
06-25 21:13:03.189: W/System.err(18144): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1265)
06-25 21:13:03.189: W/System.err(18144): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
06-25 21:13:03.189: W/System.err(18144): at dalvik.system.NativeStart.main(Native Method)
我正在AsyncTask
上进行,在doInBackGround()
下载
我做错了什么?
如果我不关闭连接,我的用户将下载内容直到最后,消耗更多数据。
答案 0 :(得分:2)
你有NetworkOnMainThreadExeption
。显然onCancel()
中的代码在主ui线程上运行。您可以更好地检查ps.isCancelled()
中的doInBackground
并取消/中止并关闭。{1}}或者开始一个帖子。