I have a UI thread(MainActivity) calling an AsynTask object(DownloadManager), which, in turn calls 3 threads (DownloaderThread).
How do I pause/resume the 3 DownloaderThreads without pausing the AsynTask or the UI thread?
Following is the code I have currently implemented for the pause functionality, but when the Pause button is clicked, the app crashes with the dialog: "app has stopped". Code:
DownloadManager (AsynTask):
public void onPause() {
try{
t0.wait();
t1.wait();
t2.wait();
this.wait();
}catch (InterruptedException ex){
}
}
DownloaderThread (implements Runnable and is passed to a Thread instance in DownloadManager:
public class DownloaderThread implements Runnable {
private Object mPauseLock;
private Boolean mPaused;
private Boolean mFinished;
public void run(){
android.os.Process.setThreadPriority(android.os.Process.THREAD_PRIORITY_BACKGROUND);
try{
while(!mFinished){
//do something
synchronized (mPauseLock){
while (mPaused){
try{
mPauseLock.wait();
}catch (InterruptedException e){
}
}
}
}
}
}
public void onPause(){
synchronized (mPauseLock){
mPaused = true;
}
}
You can't really pause an AsyncTask once it started. You can, however, store the progress when activity is paused/destroyed and start from the progress once you are back to the original Activity. But I recommend the best way to complete task for your scenario is to use Service .
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