What is context android? A Context is a handle to the system; it provides services like resolving resources, obtaining access to databases and preferences, and so on. An Android app has activities. Context is like a handle to the environment your application is currently running in.
The activity object inherits the Context object. What is an activity in Android? An Android activity is one screen of the Android app's user interface. In that way an Android activity is very similar to windows in a desktop application.
An Android app may contain one or more activities, meaning one or more screens. It allows you to define the programming interface that both the client and service agree upon in order to communicate with each other using interprocess communication IPC.
Can we update UI from service in Android? We can not update User interface from service directly to show progress in android. In service class we will create a Binder to return the object of current service. Here onBind will return service class object when service will connected. 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. Optimizing for Battery Life. System tracing. Build and test apps for accessibility. Advanced topics. Protecting against security threats with SafetyNet. Build for Billions. Build for Enterprise. App feedback. Device management. Dedicated devices. Android versions. Android Developers. The basics A bound service is an implementation of the Service class that allows other applications to bind to it and interact with it.
Binding to a started service As discussed in the Services document, you can create a service that is both started and bound. Creating a bound service When creating a service that provides binding, you must provide an IBinder that provides the programming interface that clients can use to interact with the service.
There are three ways you can define the interface: Extending the Binder class If your service is private to your own application and runs in the same process as the client which is common , you should create your interface by extending the Binder class and returning an instance of it from onBind. The client receives the Binder and can use it to directly access public methods available in either the Binder implementation or the Service.
As mentioned above, the Messenger creates a queue of all the client requests in a single thread, so the service receives requests one at a time.
Service life cycle methods are less than Activity, only onCreate, onStart, onDestroy We have two ways to start a Service, their impact on the service life cycle is different.
When you stopService, you can directly onDestroy. If the caller exits directly without calling stopService, the Service will always run in the background, and the caller can still stopService next time it gets up. At this time, the caller and the Service are bound together.
The so-called binding will coexist and die. To Note: The onCreate method of Service will only be called once, That is, no matter how many times you startService and bindService, Service is created only once. If it is bind first, then run the onStart method of Service directly when starting, If it is start first, then run the onBind method directly when bind. If you do not want to communicate with the Service you can use just startService. You Can see below diffrence between service and bind service.
A service is "started" when an application component such as an activity starts it by calling startService. Once started, a service can run in the background indefinitely, even if the component that started it is destroyed.
Usually, a started service performs a single operation and does not return a result to the caller. For example, it might download or upload a file over the network.
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