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package course.labs.notificationslab;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.URL;
import android.app.Activity;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.AsyncTask;
import android.util.Log;
import android.widget.RemoteViews;
public class DownloaderTask extends AsyncTask<String, Void, String[]> {
private static final int SIM_NETWORK_DELAY = 5000;
private static final String TAG = "Lab-Notifications";
private final int MY_NOTIFICATION_ID = 11151990;
private String mFeeds[] = new String[3];
private MainActivity mParentActivity;
private Context mApplicationContext;
// Change this variable to false if you do not have a stable network
// connection
private static final boolean HAS_NETWORK_CONNECTION = true;
// Raw feed file IDs used if you do not have a stable connection
public static final int txtFeeds[] = { R.raw.tswift, R.raw.rblack, R.raw.lgaga };
// Constructor
public DownloaderTask(MainActivity parentActivity) {
super();
mParentActivity = parentActivity;
mApplicationContext = parentActivity.getApplicationContext();
}
@Override
protected String[] doInBackground(String... urlParameters) {
log("Entered doInBackground()");
return download(urlParameters);
}
private String[] download(String urlParameters[]) {
boolean downloadCompleted = false;
try {
for (int idx = 0; idx < urlParameters.length; idx++) {
URL url = new URL(urlParameters[idx]);
try {
Thread.sleep(SIM_NETWORK_DELAY);
} catch (InterruptedException e) {
e.printStackTrace();
}
InputStream inputStream;
BufferedReader in;
// Alternative for students without
// a network connection
if (HAS_NETWORK_CONNECTION) {
inputStream = url.openStream();
in = new BufferedReader(new InputStreamReader(inputStream));
} else {
inputStream = mApplicationContext.getResources().openRawResource(txtFeeds[idx]);
in = new BufferedReader(new InputStreamReader(inputStream));
}
String readLine;
StringBuffer buf = new StringBuffer();
while ((readLine = in.readLine()) != null) {
buf.append(readLine);
}
mFeeds[idx] = buf.toString();
if (null != in) {
in.close();
}
}
downloadCompleted = true;
} catch (IOException e) {
e.printStackTrace();
}
log("Tweet Download Completed:" + downloadCompleted);
notify(downloadCompleted);
return mFeeds;
}
// Call back to the MainActivity to update the feed display
@Override
protected void onPostExecute(String[] result) {
super.onPostExecute(result);
if (mParentActivity != null) {
mParentActivity.setRefreshed(result);
}
}
// If necessary, notifies the user that the tweet downloads are complete.
// Sends an ordered broadcast back to the BroadcastReceiver in MainActivity
// to determine whether the notification is necessary.
private void notify(final boolean success) {
log("Entered notify()");
final Intent restartMainActivtyIntent = new Intent(mApplicationContext, MainActivity.class);
restartMainActivtyIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
if (success) {
// Save tweets to a file
saveTweetsToFile();
}
// Sends an ordered broadcast to determine whether MainActivity is
// active and in the foreground. Creates a new BroadcastReceiver
// to receive a result indicating the state of MainActivity
// The Action for this broadcast Intent is MainActivity.DATA_REFRESHED_ACTION
// The result Activity.RESULT_OK, indicates that MainActivity is active and
// in the foreground.
mApplicationContext.sendOrderedBroadcast(
new Intent(MainActivity.DATA_REFRESHED_ACTION), null, new BroadcastReceiver() {
final String failMsg = "Download has failed. Please retry Later.";
final String successMsg = "Download completed successfully.";
@Override
public void onReceive(Context context, Intent intent) {
log("Entered result receiver's onReceive() method");
if (getResultCode() == Activity.RESULT_OK) {
final PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
// Uses R.layout.custom_notification for the
// layout of the notification View. The xml
// file is in res/layout/custom_notification.xml
RemoteViews mContentView = new RemoteViews(
mApplicationContext.getPackageName(),
R.layout.custom_notification);
mContentView.setTextViewText(R.id.text, successMsg);
Notification.Builder notificationBuilder = new Notification.Builder(context);
notificationBuilder.setContentIntent(pendingIntent);
notificationBuilder.setContent(mContentView);
notificationBuilder.setSmallIcon(android.R.drawable.stat_sys_warning);
notificationBuilder.setAutoCancel(true);
log("Notification Area Notification sent");
}
}
}, null, 0, null, null);
}
// Saves the tweets to a file
private void saveTweetsToFile() {
PrintWriter writer = null;
try {
FileOutputStream fos = mApplicationContext.openFileOutput(
MainActivity.TWEET_FILENAME, Context.MODE_PRIVATE);
writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(
fos)));
for (String s : mFeeds) {
writer.println(s);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (null != writer) {
writer.close();
}
}
}
// Simplified log output method
private void log(String msg) {
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
Log.i(TAG, msg);
}
}
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