Android 在一天中的特定时间拍照
我的应用程序应该在一天中的特定时间拍摄背景照片。我将使用AlarmManager,但我想知道实现我的应用程序行为(即拍照)的类是否应该扩展服务或广播接收器。您认为如何?您应该将IntentDrive与AlamAnger一起使用,并在活动中定义广播接收器Android 在一天中的特定时间拍照,android,service,camera,broadcastreceiver,Android,Service,Camera,Broadcastreceiver,我的应用程序应该在一天中的特定时间拍摄背景照片。我将使用AlarmManager,但我想知道实现我的应用程序行为(即拍照)的类是否应该扩展服务或广播接收器。您认为如何?您应该将IntentDrive与AlamAnger一起使用,并在活动中定义广播接收器 public class DownloadService extends IntentService { private int result = Activity.RESULT_CANCELED; public static final S
public class DownloadService extends IntentService {
private int result = Activity.RESULT_CANCELED;
public static final String URL = "urlpath";
public static final String FILENAME = "filename";
public static final String FILEPATH = "filepath";
public static final String RESULT = "result";
public static final String NOTIFICATION = "com.vogella.android.service.receiver";
public DownloadService() {
super("DownloadService");
}
// Will be called asynchronously be Android
@Override
protected void onHandleIntent(Intent intent) {
String urlPath = intent.getStringExtra(URL);
String fileName = intent.getStringExtra(FILENAME);
File output = new File(Environment.getExternalStorageDirectory(),
fileName);
if (output.exists()) {
output.delete();
}
InputStream stream = null;
FileOutputStream fos = null;
try {
URL url = new URL(urlPath);
stream = url.openConnection().getInputStream();
InputStreamReader reader = new InputStreamReader(stream);
fos = new FileOutputStream(output.getPath());
int next = -1;
while ((next = reader.read()) != -1) {
fos.write(next);
}
// Successful finished
result = Activity.RESULT_OK;
} catch (Exception e) {
e.printStackTrace();
} finally {
if (stream != null) {
try {
stream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (fos != null) {
try {
fos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
publishResults(output.getAbsolutePath(), result);
}
private void publishResults(String outputPath, int result) {
Intent intent = new Intent(NOTIFICATION);
intent.putExtra(FILEPATH, outputPath);
intent.putExtra(RESULT, result);
sendBroadcast(intent);
}
}
public class MainActivity extends Activity {
private TextView textView;
private BroadcastReceiver receiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
Bundle bundle = intent.getExtras();
if (bundle != null) {
String string = bundle.getString(DownloadService.FILEPATH);
int resultCode = bundle.getInt(DownloadService.RESULT);
if (resultCode == RESULT_OK) {
Toast.makeText(MainActivity.this,
"Download complete. Download URI: " + string,
Toast.LENGTH_LONG).show();
textView.setText("Download done");
} else {
Toast.makeText(MainActivity.this, "Download failed",
Toast.LENGTH_LONG).show();
textView.setText("Download failed");
}
}
}
})
我在某个地方读到过,当处理广播时,应用程序会得到一组固定的时间(目前为10秒)来完成它的工作。如果没有在这段时间内完成,应用程序将被视为行为异常,其进程将立即进入后台状态,以便在需要时为内存而终止。基于此,即使拍摄照片和执行一些基本操作的过程需要10秒以上,我也应该使用广播吗?这种情况很少发生,但如果您想这样做,请在任务需要10秒以上时忽略发送广播…返回您的代码,即使手机处于睡眠或深度睡眠模式,它是否也会激活?
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
textView = (TextView) findViewById(R.id.status);
}
@Override
protected void onResume() {
super.onResume();
registerReceiver(receiver, new IntentFilter(DownloadService.NOTIFICATION));
}
@Override
protected void onPause() {
super.onPause();
unregisterReceiver(receiver);
}
public void onClick(View view) {
Intent intent = new Intent(this, DownloadService.class);
PendingIntent pintent = PendingIntent.getService(this, 0, intent, 0);
AlarmManager alarm = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
// Start every 30 seconds
alarm.setRepeating(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), 30*1000, pintent);
}
}