In order to meet Android target API 26 requirements for my app, I modified the background service in my app to be launched with a JobScheduler instead of just as a plain service. Here is my updated code.
In my PhoneUtils class,
public static void scheduleTTSJob(Context context) {
if(isTTSJobServiceOn(context))
{
return;
}
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.M) {
ComponentName serviceComponent = new ComponentName(context, TTSJobScheduledService.class);
JobInfo.Builder builder = new JobInfo.Builder(JOB_ID, serviceComponent);
builder.setMinimumLatency(1 * 1000); // wait at least
builder.setOverrideDeadline(3 * 1000); // maximum delay
JobScheduler jobScheduler = context.getSystemService(JobScheduler.class);
jobScheduler.schedule(builder.build());
}
}
public static boolean isTTSJobServiceOn( Context context ) {
boolean hasBeenScheduled = false;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
JobScheduler scheduler = (JobScheduler) context.getSystemService( Context.JOB_SCHEDULER_SERVICE );
for ( JobInfo jobInfo : scheduler.getAllPendingJobs() ) {
if ( jobInfo.getId() == JOB_ID ) {
hasBeenScheduled = true;
break;
}
}
}
return hasBeenScheduled;
}
public static void stopTTSJob(Context context)
{
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
JobScheduler scheduler = (JobScheduler) context.getSystemService( Context.JOB_SCHEDULER_SERVICE );
for ( JobInfo jobInfo : scheduler.getAllPendingJobs() ) {
if ( jobInfo.getId() == JOB_ID ) {
scheduler.cancel(JOB_ID);
break;
}
}
}
}
TTSJobScheduledService class
package services;
import android.annotation.TargetApi;
import android.app.job.JobParameters;
import android.app.job.JobService;
import android.content.Intent;
import android.os.Build;
import utilities.PhoneUtils;
@TargetApi(Build.VERSION_CODES.LOLLIPOP)
public class TTSJobScheduledService extends JobService {
@Override
public boolean onStartJob(JobParameters params) {
Intent service = new Intent(getApplicationContext(), TTSService.class);
getApplicationContext().startService(service);
PhoneUtils.scheduleTTSJob(getApplicationContext()); // reschedule the job
return true;
}
@Override
public boolean onStopJob(JobParameters params) {
return true;
}
}
Code for TTSService class:
package services;
import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import android.speech.tts.TextToSpeech;
import android.support.annotation.Nullable;
public class TTSService extends Service {
private static TextToSpeech voice =null;
public static TextToSpeech getVoice() {
return voice;
}
@Nullable
@Override
public IBinder onBind(Intent intent) {
// not supporting binding
return null;
}
public TTSService() {
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
try{
voice = new TextToSpeech(TTSService.this, new TextToSpeech.OnInitListener() {
@Override
public void onInit(final int status) {
}
});
}
catch(Exception e){
e.printStackTrace();
}
return Service.START_STICKY;
}
@Override
public void onDestroy() {
clearTtsEngine();
super.onDestroy();
}
public static void clearTtsEngine()
{
if(voice!=null)
{
voice.stop();
voice.shutdown();
voice = null;
}
}
}
Also, I added this new service in my manifest file:
<service
android:name="services.TTSJobScheduledService"
android:label="TTS service"
android:permission="android.permission.BIND_JOB_SERVICE" >
</service>
I am scheduling this service when user opens my app (if it is not already scheduled), or if device is rebooted, or if app is upgraded on Google Play.
However, soon after I released this app update, I started getting crashes with this stack trace for devices with Android 8.0.0 and above:
Caused by java.lang.IllegalStateException: Not allowed to start service Intent { cmp=abc.fgh.com.abc/services.TTSService }: app is in background uid UidRecord{6dafcbe u0a250 TRNB idle procs:1 seq(0,0,0)}
at android.app.ContextImpl.startServiceCommon(ContextImpl.java:1505)
at android.app.ContextImpl.startService(ContextImpl.java:1461)
at android.content.ContextWrapper.startService(ContextWrapper.java:644)
at services.TTSJobScheduledService.onStartJob(Unknown Source:15)
at android.app.job.JobService$1.onStartJob(JobService.java:71)
at android.app.job.JobServiceEngine$JobHandler.handleMessage(JobServiceEngine.java:108)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:180)
at android.app.ActivityThread.main(ActivityThread.java:6950)
at java.lang.reflect.Method.invoke(Method.java)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:835)
As I understand, this should not be happening given that I am using a JobScheduledService scheduleTTSJob() call and not a plain startService() call from my code. It did not crash on device I tested it on (Moto G6), which is also having Android 8.0.0, but is now crashing on these other devices with Android 8.0.0 and above.
As I understand, this should not be happening given that I am using a JobScHeduledService scheduleTTSJob() call and not a plain startService() call from my code
You are definitely using a plain startService() call from your code. It is in your onStartJob() method:
@Override
public boolean onStartJob(JobParameters params) {
Intent service = new Intent(getApplicationContext(), TTSService.class);
getApplicationContext().startService(service);
PhoneUtils.scheduleTTSJob(getApplicationContext()); // reschedule the job
return true;
}
and that is where the stack trace shows that you are crashing.
Please let me know what is the fix to be made in my code
Either:
Delete that startService() call, or
Use ContextCompat.startForegroundService() and have TTSService call startForeground() as it starts up, or
If applicable, move that TTSService logic into some non-service code in a background thread that you execute directly from onStartJob()
It is difficult to give you more specific advice, given that we do not know what TTSService is.