As I above discussed that your service will destroy or killed by Android OS if anything happened wrong like low memory or memory is not enough to execute the task.
In this case, we can make our service as per our requirement. Service provides the option for you to make accordingly. You can set the flag. But before make sure that you do not pass any intent data because intent data will be lost when service is killed. So we will receive null intent data on startCommand. You can set your flag as below. Intent service is running on the worker thread, not by main thread or UI thread.
You can not update any UI here because it always running by the background thread. It can be used for long operation kind of task for example for downloading files from the server etc. It can also start service from activity or broadcast receiver. When you start service from here itslife cycle method will be executed. Service is created once called the onCreate and after it will be running on onHandleIntent.
Here you can do some task. Service will destroy it will be called onDestroy method. Intent service automatically stopped once it will complete the task. If you have multiple tasks running it will handle one task at one time and other tasks will be in a queue. The notification in the status bar might indicate the current song and allow the user to launch an activity to interact with the music player.
For more information about notifications, see Creating Status Bar Notifications. We only need to call the startForeground method in onStartCommand to let the service run in the foreground, and then call stopForeground in onDestroy to cancel the foreground run! Get the currently running services through the method ActivityManager. We use the service to perform a long-term background action. In order not to block the thread, however, Thread can achieve this effect.
Why don't we directly use Thread to replace the service? Thread: Thread is the smallest unit of program execution , and it is the basic unit for allocating CPU. You can use Thread to perform some asynchronous operations. Service: Service is a mechanism of android.
When it is running, if it is a Local Service, the corresponding Service is running on the main thread of the main process. Such as: onCreate, onStart these functions are run on the main thread of the main process when they are called by the system. If it is a Remote Service, then the corresponding Service is running on the main thread of an independent process. So please don't interpret Service as a thread, it has nothing to do with thread half a dime!
In this case, why do we use Service? In fact, this is related to the Android system mechanism, let's take Thread first. The operation of Thread is independent of Activity, which means that after an Activity is finished, if you do not actively stop the Thread or the run method in the Thread has not been executed, the Thread will continue to execute. Therefore, there will be a problem: when the Activity is finished, you no longer hold a reference to the Thread.
On the other hand, you have no way to control the same Thread in different Activities. For example: if your Thread needs to connect to the server at intervals of time to do some synchronization, the Thread needs to be running when the Activity is not started. At this time, when you start an Activity, there is no way to control the previously created Thread in the Activity.
Therefore, you need to create and start a Service, create, run and control the Thread in the Service, which solves the problem because any Activity can control the same Service, and the system will only create an instance of the corresponding Service.
A service has life cycle callback methods that you can implement to monitor changes in the service's state and you can perform work at the appropriate stage.
The following diagram on the left shows the life cycle when the service is created with startService and the diagram on the right shows the life cycle when the service is created with bindService : image courtesy : android. To create an service, you create a Java class that extends the Service base class or one of its existing subclasses. The Service base class defines various callback methods and the most important are given below.
You don't need to implement all the callbacks methods. However, it's important that you understand each one and implement those that ensure your app behaves the way users expect. The system calls this method when another component, such as an activity, requests that the service be started, by calling startService.
If you implement this method, it is your responsibility to stop the service when its work is done, by calling stopSelf or stopService methods. The system calls this method when another component wants to bind with the service by calling bindService.
If you implement this method, you must provide an interface that clients use to communicate with the service, by returning an IBinder object. You must always implement this method, but if you don't want to allow binding, then you should return null. Manage device awake state. Save to shared storage.
Save data in a local database. Sharing simple data. Sharing files. Sharing files with NFC. Printing files. Content providers. Autofill framework. Contacts provider. Data backup. Remember and authenticate users.
User location. Using touch gestures. Handling keyboard input. Supporting game controllers. Input method editors. Performing network operations. Transmit network data using Volley. Perform network operations using Cronet.
Transferring data without draining the battery. Reduce network battery drain. Transfer data using Sync Adapters. Bluetooth Low Energy.
Wi-Fi infrastructure. Discover and connect. Runtime API reference. Web-based content. Android App Bundles. Google Play. Play Asset Delivery. Play Feature Delivery. In-app reviews.
In-app updates. Google Play Instant. Get started with instant apps. Get started with instant games. Integrate with Firebase. Play Install Referrer.
Play Install Referrer Library. Application Licensing. Android GPU Inspector. System profiling. Analyze a system profile. GPU performance counters. Frame profiling.
Analyze a frame profile. Frame Profiler UI. Customize or port game engines. Process input events. Support game controllers.
Achieve proper frame pacing. Frame pacing in Vulkan. Integrate Android Performance Tuner. Output audio. Manage memory. Use prebuilt or turnkey game engines. Develop with Defold. Develop with Godot. Develop with Unity. Use Android Performance Tuner. Game best practices. Maximize device availability. Art assets. OpenGL and Vulkan. Game Mode. Best practices. Building effective unit tests.
Automating UI tests. Testing app component integrations. Android Vitals.
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