What is the difference between service, intentServ

问题:

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• Service vs IntentService 10 answers

What is the difference between Service and an IntentService in Android?

What is the difference between AsyncTask and an IntentService in Android?

回答1:

1. Difference between Service and IntentService

Service: It is the base class for the Android services, that you can extend for creating any service. Since the service run inside the UI thread, it requires that you create a working thread for executing its work.

IntentService: it is a subclass of Service, that simplifies your work. It works already in a working thread, and can receive asynchronous requests. So, you don't need to create it manually, or to worry about synchronization. You can simply extend it and override the method:

onHandleIntent(Intent intent)

where you can manage all the incoming requests.

Taking a look at the documentation, you can see in details what the IntentService do for you:

• Creates a default worker thread that executes all intents delivered to onStartCommand() separate from your application's main thread.
• Creates a work queue that passes one intent at a time to your onHandleIntent() implementation, so you never have to worry about multi-threading.
• Stops the service after all start requests have been handled, so you never have to call stopSelf().
• Provides default implementation of onBind() that returns null.
• Provides a default implementation of onStartCommand() that sends the intent to the work queue and then to your onHandleIntent() implementation.

So, if you need more control you can use the Service class, but often for a simple service the best solution is the IntentService.

2. Difference between AsyncTask and Service

They are two different concepts.

Service: can be intended as an Activity with no interface. It is suitable for long-running operations.

AsyncTask: is a particular class that wraps a working thread (performing background operations), facilitating the interaction with the UI Thread, without managing threads or handlers directly.

回答2:

In short, a Service is a broader implementation for the developer to set up background operations, while an IntentService is useful for "fire and forget" operations, taking care of background Thread creation and cleanup.

From the docs:

Service A Service is an application component representing either an application's desire to perform a longer-running operation while not interacting with the user or to supply functionality for other applications to use.

IntentService IntentService is a base class for Services that handle asynchronous requests (expressed as Intents) on demand. Clients send requests through startService(Intent) calls; the service is started as needed, handles each Intent in turn using a worker thread, and stops itself when it runs out of work.

Service vs IntentService

What is the difference between an IntentService and a Service?