Android-Job
A utility library for Android to run jobs delayed in the background. Depending on the Android version either the JobScheduler, GcmNetworkManager or AlarmManager is getting used. You can find out in this blog post or in these slides why you should prefer this library than each separate API. All features from Android Oreo are backward compatible back to Ice Cream Sandwich.
Download
Download the latest version or grab via Gradle:
dependencies {
compile 'com.evernote:android-job:1.2.0'
}
If you didn't turn off the manifest merger from the Gradle build tools, then no further step is required to setup the library. Otherwise you manually need to add the permissions and services like in this AndroidManifest.
You can read the JavaDoc here.
Usage
The class JobManager serves as entry point. Your jobs need to extend the class Job. Create a JobRequest with the corresponding builder class and schedule this request with the JobManager.
Before you can use the JobManager you must initialize the singleton. You need to provide a Context and add a JobCreator implementation after that. The JobCreator maps a job tag to a specific job class. It's recommended to initialize the JobManager in the onCreate() method of your Application object, but there is an alternative, if you don't have access to the Application class.
public class App extends Application {
@Override
public void onCreate() {
super.onCreate();
JobManager.create(this).addJobCreator(new DemoJobCreator());
}
}
public class DemoJobCreator implements JobCreator {
@Override
@Nullable
public Job create(@NonNull String tag) {
switch (tag) {
case DemoSyncJob.TAG:
return new DemoSyncJob();
default:
return null;
}
}
}
After that you can start scheduling jobs.
public class DemoSyncJob extends Job {
public static final String TAG = "job_demo_tag";
@Override
@NonNull
protected Result onRunJob(Params params) {
// run your job here
return Result.SUCCESS;
}
public static void scheduleJob() {
new JobRequest.Builder(DemoSyncJob.TAG)
.setExecutionWindow(30_000L, 40_000L)
.build()
.schedule();
}
}
Advanced
The JobRequest.Builder class has many extra options, e.g. you can specify a required network connection, make the job periodic, pass some extras with a bundle, restore the job after a reboot or run the job at an exact time.
Each job has a unique ID. This ID helps to identify the job later to update requirements or to cancel the job.
private void scheduleAdvancedJob() {
PersistableBundleCompat extras = new PersistableBundleCompat();
extras.putString("key", "Hello world");
int jobId = new JobRequest.Builder(DemoSyncJob.TAG)
.setExecutionWindow(30_000L, 40_000L)
.setBackoffCriteria(5_000L, JobRequest.BackoffPolicy.EXPONENTIAL)
.setRequiresCharging(true)
.setRequiresDeviceIdle(false)
.setRequiredNetworkType(JobRequest.NetworkType.CONNECTED)
.setExtras(extras)
.setRequirementsEnforced(true)
.setUpdateCurrent(true)
.build()
.schedule();
}
private void schedulePeriodicJob() {
int jobId = new JobRequest.Builder(DemoSyncJob.TAG)
.setPeriodic(TimeUnit.MINUTES.toMillis(15), TimeUnit.MINUTES.toMillis(5))
.build()
.schedule();
}
private void scheduleExactJob() {
int jobId = new JobRequest.Builder(DemoSyncJob.TAG)
.setExact(20_000L)
.build()
.schedule();
}
private void runJobImmediately() {
int jobId = new JobRequest.Builder(DemoSyncJob.TAG)
.startNow()
.build()
.schedule();
}
private void cancelJob(int jobId) {
JobManager.instance().cancel(jobId);
}
If a non periodic Job fails, then you can reschedule it with the defined back-off criteria.
public class RescheduleDemoJob extends Job {
@Override
@NonNull
protected Result onRunJob(Params params) {
// something strange happened, try again later
return Result.RESCHEDULE;
}
@Override
protected void onReschedule(int newJobId) {
// the rescheduled job has a new ID
}
}
Proguard
The library doesn't use reflection, but it relies on three Services and two BroadcastReceivers. In order to avoid any issues, you shouldn't obfuscate those four classes. The library bundles its own Proguard config and you don't need to do anything, but just in case you can add these rules in your configuration.
More questions?
Google Play Services
This library does not automatically bundle the Google Play Services, because the dependency is really heavy and not all apps want to include them. That's why you need to add the dependency manually, if you want that the library uses the GcmNetworkManager on Android 4.
dependencies {
compile "com.google.android.gms:play-services-gcm:latest_version"
}
Crashes after removing the GCM dependency is a known limitation of the Google Play Services. Please take a look at this workaround to avoid those crashes.
License
Copyright (c) 2007-2017 by Evernote Corporation, All rights reserved. Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.