Vous devez utiliser looper pour le téléchargement lisse pour plusieurs fichiers, il les téléchargera un par un. De cette façon, votre application fonctionne en douceur énorme quantité de téléchargements.
Comment utiliser Looper
public class MainActivity extends Activity implements DownloadThreadListener,
OnClickListener {
private DownloadThread downloadThread;
private Handler handler;
private ProgressBar progressBar;
private TextView statusText;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Create and launch the download thread
downloadThread = new DownloadThread(this);
downloadThread.start();
// Create the Handler. It will implicitly bind to the Looper
// that is internally created for this thread (since it is the UI
// thread)
handler = new Handler();
progressBar = (ProgressBar) findViewById(R.id.progress_bar);
statusText = (TextView) findViewById(R.id.status_text);
Button scheduleButton = (Button) findViewById(R.id.schedule_button);
scheduleButton.setOnClickListener(this);
}
@Override
protected void onDestroy() {
super.onDestroy();
// request the thread to stop
downloadThread.requestStop();
}
// note! this might be called from another thread
@Override
public void handleDownloadThreadUpdate() {
// we want to modify the progress bar so we need to do it from the UI
// thread
// how can we make sure the code runs in the UI thread? use the handler!
handler.post(new Runnable() {
@Override
public void run() {
int total = downloadThread.getTotalQueued();
int completed = downloadThread.getTotalCompleted();
progressBar.setMax(total);
progressBar.setProgress(0); // need to do it due to a
// ProgressBar bug
progressBar.setProgress(completed);
statusText.setText(String.format("Downloaded %d/%d", completed,
total));
// vibrate for fun
if (completed == total) {
((Vibrator) getSystemService(VIBRATOR_SERVICE))
.vibrate(100);
}
}
});
}
@Override
public void onClick(View source) {
if (source.getId() == R.id.schedule_button) {
int totalTasks = new Random().nextInt(3) + 1;
for (int i = 0; i < totalTasks; ++i) {
downloadThread.enqueueDownload(new DownloadTask());
}
}
}
}
DownloadThread.Class
public final class DownloadThread extends Thread {
private static final String TAG = DownloadThread.class.getSimpleName();
private Handler handler;
private int totalQueued;
private int totalCompleted;
private DownloadThreadListener listener;
public DownloadThread(DownloadThreadListener listener) {
this.listener = listener;
}
@Override
public void run() {
try {
// preparing a looper on current thread
// the current thread is being detected implicitly
Looper.prepare();
Log.i(TAG, "DownloadThread entering the loop");
// now, the handler will automatically bind to the
// Looper that is attached to the current thread
// You don't need to specify the Looper explicitly
handler = new Handler();
// After the following line the thread will start
// running the message loop and will not normally
// exit the loop unless a problem happens or you
// quit() the looper (see below)
Looper.loop();
Log.i(TAG, "DownloadThread exiting gracefully");
} catch (Throwable t) {
Log.e(TAG, "DownloadThread halted due to an error", t);
}
}
// This method is allowed to be called from any thread
public synchronized void requestStop() {
// using the handler, post a Runnable that will quit()
// the Looper attached to our DownloadThread
// obviously, all previously queued tasks will be executed
// before the loop gets the quit Runnable
handler.post(new Runnable() {
@Override
public void run() {
// This is guaranteed to run on the DownloadThread
// so we can use myLooper() to get its looper
Log.i(TAG, "DownloadThread loop quitting by request");
Looper.myLooper().quit();
}
});
}
public synchronized void enqueueDownload(final DownloadTask task) {
// Wrap DownloadTask into another Runnable to track the statistics
handler.post(new Runnable() {
@Override
public void run() {
try {
task.run();
} finally {
// register task completion
synchronized (DownloadThread.this) {
totalCompleted++;
}
// tell the listener something has happened
signalUpdate();
}
}
});
totalQueued++;
// tell the listeners the queue is now longer
signalUpdate();
}
public synchronized int getTotalQueued() {
return totalQueued;
}
public synchronized int getTotalCompleted() {
return totalCompleted;
}
// Please note! This method will normally be called from the download
// thread.
// Thus, it is up for the listener to deal with that (in case it is a UI
// component,
// it has to execute the signal handling code in the UI thread using Handler
// - see
// DownloadQueueActivity for example).
private void signalUpdate() {
if (listener != null) {
listener.handleDownloadThreadUpdate();
}
}
}
DownloadTask.Class
public class DownloadTask implements Runnable {
private static final String TAG = DownloadTask.class.getSimpleName();
private static final Random random = new Random();
private int lengthSec;
public DownloadTask() {
lengthSec = random.nextInt(3) + 1;
}
@Override
public void run() {
try {
Thread.sleep(lengthSec * 1000);
// it's a good idea to always catch Throwable
// in isolated "codelets" like Runnable or Thread
// otherwise the exception might be sunk by some
// agent that actually runs your Runnable - you
// never know what it might be.
} catch (Throwable t) {
Log.e(TAG, "Error in DownloadTask", t);
}
}
}
DownloadThreadListener.class (Interface)
public interface DownloadThreadListener {
void handleDownloadThreadUpdate();
}
En utilisant cela, vous pouvez ajouter énorme quantité de téléchargements il les ajoutera la file d'attente. Complete tutorial
Comment voulez-vous que les appels soient faits? L'un après l'autre? –
Non .. Je dois faire un appel et quand le premier est fini, en faire un autre. C'est pourquoi parfois j'ai besoin du résultat du premier –