我正在开发一个聊天应用程序，为了实时获取新消息，我们使用前台服务。（由于某些情况我们不能使用 FCM）为了确保客户端连接到服务器，我们使用 JobScheduler 每 1 分钟向服务器发送一次 ping。现在我们遇到了电池使用问题。最好在我们的前台服务中使用 CountDownTimer 之类的代码：
CountDownTimer countDownTimerPingPeriodic;
public static boolean isPinging;
public void pingPeriodic(boolean fromService) {
if (countDownTimerPingPeriodic != null) {
countDownTimerPingPeriodic.cancel();
countDownTimerPingPeriodic = null;
}
new Handler(Looper.getMainLooper()).post(new Runnable() {
@Override
public void run() {
long future = 75000;
countDownTimerPingPeriodic =
new CountDownTimer(60000, 60000) {
@Override
public void onTick(long l) {
}
@Override
public void onFinish() {
sendPing(false);
pingPeriodic(false);
}
};
isPinging = true;
countDownTimerPingPeriodic.start();
}
});
}
或者最好使用下面的工作服务（现在我们使用下面的代码并在 onStartJob 中发送 ping）：
public class ScheduleConnectionJob extends JobService {
private static final String TAG = "ScheduleConnectionJob";
private int i = 0;
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
return Service.START_STICKY;
}
@Override
public boolean onStartJob(JobParameters params) {
//here I will send a ping to the server
jobFinished(params, true);
Util.scheduleJob(getApplicationContext()); // reschedule the job
return true;
}
@Override
public boolean onStopJob(JobParameters params) {
Util.scheduleJob(getApplicationContext());
return true;
}
@Override
public void onDestroy() {
super.onDestroy();
Util.scheduleJob(getApplicationContext());
}}
并调用并重复此服务我们使用以下代码每 1 分钟重复一次：
public class Util {
public static final long MinimumSchadulePeriodic = 15 * 60 * 1000 ;
// schedule the start of the service every 10 - 30 seconds
public static void scheduleJob(Context context) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
ComponentName serviceComponent = new ComponentName(context, ScheduleConnectionJob.class);
JobInfo.Builder builder = new JobInfo.Builder(0, serviceComponent);
FileLog.i("Util:",
Thread.currentThread().getStackTrace()[2].getLineNumber() + " " +
"scheduleJob:scheduleJob");
builder.setMinimumLatency(MinimumSchadulePeriodic); // wait at least
builder.setOverrideDeadline(60 * 1000); // maximum delay
builder.setRequiredNetworkType(JobInfo.NETWORK_TYPE_ANY); // require unmetered network
JobScheduler jobScheduler = (JobScheduler) context.getSystemService(Context.JOB_SCHEDULER_SERVICE);
if (jobScheduler != null) {
jobScheduler.schedule(builder.build());
}
}
}}