を使用して Web から画像をダウンロードする プログラムを作成しました。ダウンロードプロセスは正常に機能します。ダウンロードの進行状況を示すために を使用しています。また、ダウンロードを開始するボタンとダウンロードを停止するボタンが 2 つあります。しかし、停止ボタンをクリックしても、進行中のダウンロードを停止できません。通知マネージャーは同じことを続けます。AsyncTaskservicenotification
主な活動：
public class ServicedownloadActivity extends Activity implements
OnClickListener {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
b1 = (Button) findViewById(R.id.button1);
b2 = (Button) findViewById(R.id.button2);
b1.setOnClickListener(this);
b2.setOnClickListener(this);
}
@Override
public void onClick(View v) {
if (v.getId() == R.id.button1) {
Intent intent = new Intent(ServicedownloadActivity.this,
Myclass.class);
startService(intent);
}
if (v.getId() == R.id.button2) {
Intent intent = new Intent(ServicedownloadActivity.this,
Myclass.class);
stopService(intent);
}
}
}
クラスにはサービスと asynchTask が含まれます
public class Myclass extends Service {
URLConnection connection;
private final Random mGenerator = new Random();
@Override
public IBinder onBind(Intent intent) {
return null;
}
public int getRandomNumber() {
return mGenerator.nextInt(100);
}
@Override
public void onCreate() {
super.onCreate();
Log.d("df", "From oncreate");
Toast.makeText(this, "on create", Toast.LENGTH_SHORT).show();
}
class DownloadWebPageTask extends AsyncTask<String, String, String> {
String responseTextt;
NotificationManager notificationManager;
Notification notification;
CharSequence contentText;
Context context;
CharSequence contentTitle;
PendingIntent contentIntent;
int HELLO_ID = 1;
long time;
int icon;
CharSequence tickerText;
public void downloadNotification() {
String ns = Context.NOTIFICATION_SERVICE;
notificationManager = (NotificationManager) getSystemService(ns);
icon = R.drawable.ic_launcher;
tickerText = "Downloading...";
time = System.currentTimeMillis();
notification = new Notification(icon, tickerText, time);
context = getApplicationContext();
contentTitle = "Your download is in progress";
contentText = "0% complete";
Intent notificationIntent = new Intent(Intent.ACTION_VIEW);
notificationIntent.setType("audio/*");
contentIntent = PendingIntent.getActivity(context, 0,
notificationIntent, 0);
notification.setLatestEventInfo(context, contentTitle,
contentText, contentIntent);
notificationManager.notify(HELLO_ID, notification);
}
@Override
protected String doInBackground(String... urls) {
try {
Log.d("trys:", "try");
URL url = new URL(
"http://www.zapiture.com/resources/IMG_6812.JPG");
connection = url.openConnection();
connection.connect();
int fileLength = connection.getContentLength();
InputStream input = new BufferedInputStream(url
.openStream());
OutputStream output = new FileOutputStream(Environment
.getExternalStorageDirectory()
+ "/img23.jpg");
byte data[] = new byte[1024];
long total = 0;
int count;
int previousProgress = 0;
while ((count = input.read(data)) != -1) {
total += count;
if ((int) (total * 100 / fileLength) > previousProgress) {
previousProgress = (int) (total * 100 / fileLength);
publishProgress(""
+ (int) (total * 100 / fileLength));
output.write(data, 0, count);
}
}
output.flush();
output.close();
input.close();
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
@Override
protected void onPreExecute() {
downloadNotification();
super.onPreExecute();
;
}
@Override
public void onProgressUpdate(String... progress) {
contentText = Integer.parseInt(progress[0]) + "% complete";
notification.setLatestEventInfo(context, contentTitle,
contentText, contentIntent);
notificationManager.notify(HELLO_ID, notification);
super.onProgressUpdate(progress);
}
}
@Override
public void onStart(Intent intent, int startId) {
// TODO Auto-generated method stub
super.onStart(intent, startId);
Log.d("sf", "On Start");
Toast.makeText(this, "on start", Toast.LENGTH_SHORT).show();
DownloadWebPageTask task = new DownloadWebPageTask();
task.execute();
}
@Override
public void onDestroy() {
stopSelf();
super.onDestroy();
Log.d("df", "From on Destroy");
Toast.makeText(this, "on destroy", Toast.LENGTH_SHORT).show();
}
}