680 lines
31 KiB
Java
680 lines
31 KiB
Java
/*
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* Copyright (C) 2006 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package android.app;
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import android.content.ComponentCallbacks;
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import android.content.ComponentName;
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import android.content.Intent;
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import android.content.ContextWrapper;
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import android.content.Context;
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import android.content.res.Configuration;
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import android.os.Build;
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import android.os.RemoteException;
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import android.os.IBinder;
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import android.util.Log;
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import java.io.FileDescriptor;
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import java.io.PrintWriter;
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/**
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* A Service is an application component representing either an application's desire
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* to perform a longer-running operation while not interacting with the user
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* or to supply functionality for other applications to use. Each service
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* class must have a corresponding
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* {@link android.R.styleable#AndroidManifestService <service>}
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* declaration in its package's <code>AndroidManifest.xml</code>. Services
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* can be started with
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* {@link android.content.Context#startService Context.startService()} and
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* {@link android.content.Context#bindService Context.bindService()}.
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*
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* <p>Note that services, like other application objects, run in the main
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* thread of their hosting process. This means that, if your service is going
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* to do any CPU intensive (such as MP3 playback) or blocking (such as
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* networking) operations, it should spawn its own thread in which to do that
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* work. More information on this can be found in
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* <a href="{@docRoot}guide/topics/fundamentals.html#procthread">Application Fundamentals:
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* Processes and Threads</a>. The {@link IntentService} class is available
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* as a standard implementation of Service that has its own thread where it
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* schedules its work to be done.</p>
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*
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* <p>The Service class is an important part of an
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* <a href="{@docRoot}guide/topics/fundamentals.html#lcycles">application's overall lifecycle</a>.</p>
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*
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* <p>Topics covered here:
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* <ol>
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* <li><a href="#WhatIsAService">What is a Service?</a>
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* <li><a href="#ServiceLifecycle">Service Lifecycle</a>
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* <li><a href="#Permissions">Permissions</a>
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* <li><a href="#ProcessLifecycle">Process Lifecycle</a>
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* <li><a href="#LocalServiceSample">Local Service Sample</a>
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* <li><a href="#RemoteMessengerServiceSample">Remote Messenger Service Sample</a>
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* </ol>
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*
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* <a name="WhatIsAService"></a>
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* <h3>What is a Service?</h3>
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*
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* <p>Most confusion about the Service class actually revolves around what
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* it is <em>not</em>:</p>
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*
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* <ul>
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* <li> A Service is <b>not</b> a separate process. The Service object itself
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* does not imply it is running in its own process; unless otherwise specified,
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* it runs in the same process as the application it is part of.
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* <li> A Service is <b>not</b> a thread. It is not a means itself to do work off
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* of the main thread (to avoid Application Not Responding errors).
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* </ul>
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*
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* <p>Thus a Service itself is actually very simple, providing two main features:</p>
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*
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* <ul>
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* <li>A facility for the application to tell the system <em>about</em>
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* something it wants to be doing in the background (even when the user is not
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* directly interacting with the application). This corresponds to calls to
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* {@link android.content.Context#startService Context.startService()}, which
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* ask the system to schedule work for the service, to be run until the service
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* or someone else explicitly stop it.
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* <li>A facility for an application to expose some of its functionality to
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* other applications. This corresponds to calls to
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* {@link android.content.Context#bindService Context.bindService()}, which
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* allows a long-standing connection to be made to the service in order to
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* interact with it.
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* </ul>
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*
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* <p>When a Service component is actually created, for either of these reasons,
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* all that the system actually does is instantiate the component
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* and call its {@link #onCreate} and any other appropriate callbacks on the
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* main thread. It is up to the Service to implement these with the appropriate
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* behavior, such as creating a secondary thread in which it does its work.</p>
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*
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* <p>Note that because Service itself is so simple, you can make your
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* interaction with it as simple or complicated as you want: from treating it
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* as a local Java object that you make direct method calls on (as illustrated
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* by <a href="#LocalServiceSample">Local Service Sample</a>), to providing
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* a full remoteable interface using AIDL.</p>
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*
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* <a name="ServiceLifecycle"></a>
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* <h3>Service Lifecycle</h3>
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*
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* <p>There are two reasons that a service can be run by the system. If someone
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* calls {@link android.content.Context#startService Context.startService()} then the system will
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* retrieve the service (creating it and calling its {@link #onCreate} method
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* if needed) and then call its {@link #onStartCommand} method with the
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* arguments supplied by the client. The service will at this point continue
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* running until {@link android.content.Context#stopService Context.stopService()} or
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* {@link #stopSelf()} is called. Note that multiple calls to
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* Context.startService() do not nest (though they do result in multiple corresponding
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* calls to onStartCommand()), so no matter how many times it is started a service
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* will be stopped once Context.stopService() or stopSelf() is called; however,
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* services can use their {@link #stopSelf(int)} method to ensure the service is
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* not stopped until started intents have been processed.
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*
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* <p>For started services, there are two additional major modes of operation
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* they can decide to run in, depending on the value they return from
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* onStartCommand(): {@link #START_STICKY} is used for services that are
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* explicitly started and stopped as needed, while {@link #START_NOT_STICKY}
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* or {@link #START_REDELIVER_INTENT} are used for services that should only
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* remain running while processing any commands sent to them. See the linked
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* documentation for more detail on the semantics.
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*
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* <p>Clients can also use {@link android.content.Context#bindService Context.bindService()} to
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* obtain a persistent connection to a service. This likewise creates the
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* service if it is not already running (calling {@link #onCreate} while
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* doing so), but does not call onStartCommand(). The client will receive the
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* {@link android.os.IBinder} object that the service returns from its
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* {@link #onBind} method, allowing the client to then make calls back
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* to the service. The service will remain running as long as the connection
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* is established (whether or not the client retains a reference on the
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* service's IBinder). Usually the IBinder returned is for a complex
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* interface that has been <a href="{@docRoot}guide/developing/tools/aidl.html">written
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* in aidl</a>.
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*
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* <p>A service can be both started and have connections bound to it. In such
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* a case, the system will keep the service running as long as either it is
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* started <em>or</em> there are one or more connections to it with the
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* {@link android.content.Context#BIND_AUTO_CREATE Context.BIND_AUTO_CREATE}
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* flag. Once neither
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* of these situations hold, the service's {@link #onDestroy} method is called
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* and the service is effectively terminated. All cleanup (stopping threads,
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* unregistering receivers) should be complete upon returning from onDestroy().
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*
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* <a name="Permissions"></a>
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* <h3>Permissions</h3>
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*
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* <p>Global access to a service can be enforced when it is declared in its
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* manifest's {@link android.R.styleable#AndroidManifestService <service>}
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* tag. By doing so, other applications will need to declare a corresponding
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* {@link android.R.styleable#AndroidManifestUsesPermission <uses-permission>}
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* element in their own manifest to be able to start, stop, or bind to
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* the service.
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*
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* <p>In addition, a service can protect individual IPC calls into it with
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* permissions, by calling the
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* {@link #checkCallingPermission}
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* method before executing the implementation of that call.
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*
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* <p>See the <a href="{@docRoot}guide/topics/security/security.html">Security and Permissions</a>
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* document for more information on permissions and security in general.
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*
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* <a name="ProcessLifecycle"></a>
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* <h3>Process Lifecycle</h3>
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*
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* <p>The Android system will attempt to keep the process hosting a service
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* around as long as the service has been started or has clients bound to it.
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* When running low on memory and needing to kill existing processes, the
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* priority of a process hosting the service will be the higher of the
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* following possibilities:
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*
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* <ul>
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* <li><p>If the service is currently executing code in its
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* {@link #onCreate onCreate()}, {@link #onStartCommand onStartCommand()},
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* or {@link #onDestroy onDestroy()} methods, then the hosting process will
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* be a foreground process to ensure this code can execute without
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* being killed.
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* <li><p>If the service has been started, then its hosting process is considered
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* to be less important than any processes that are currently visible to the
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* user on-screen, but more important than any process not visible. Because
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* only a few processes are generally visible to the user, this means that
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* the service should not be killed except in extreme low memory conditions.
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* <li><p>If there are clients bound to the service, then the service's hosting
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* process is never less important than the most important client. That is,
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* if one of its clients is visible to the user, then the service itself is
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* considered to be visible.
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* <li><p>A started service can use the {@link #startForeground(int, Notification)}
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* API to put the service in a foreground state, where the system considers
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* it to be something the user is actively aware of and thus not a candidate
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* for killing when low on memory. (It is still theoretically possible for
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* the service to be killed under extreme memory pressure from the current
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* foreground application, but in practice this should not be a concern.)
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* </ul>
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*
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* <p>Note this means that most of the time your service is running, it may
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* be killed by the system if it is under heavy memory pressure. If this
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* happens, the system will later try to restart the service. An important
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* consequence of this is that if you implement {@link #onStartCommand onStartCommand()}
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* to schedule work to be done asynchronously or in another thread, then you
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* may want to use {@link #START_FLAG_REDELIVERY} to have the system
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* re-deliver an Intent for you so that it does not get lost if your service
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* is killed while processing it.
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*
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* <p>Other application components running in the same process as the service
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* (such as an {@link android.app.Activity}) can, of course, increase the
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* importance of the overall
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* process beyond just the importance of the service itself.
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*
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* <a name="LocalServiceSample"></a>
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* <h3>Local Service Sample</h3>
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*
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* <p>One of the most common uses of a Service is as a secondary component
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* running alongside other parts of an application, in the same process as
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* the rest of the components. All components of an .apk run in the same
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* process unless explicitly stated otherwise, so this is a typical situation.
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*
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* <p>When used in this way, by assuming the
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* components are in the same process, you can greatly simplify the interaction
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* between them: clients of the service can simply cast the IBinder they
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* receive from it to a concrete class published by the service.
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*
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* <p>An example of this use of a Service is shown here. First is the Service
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* itself, publishing a custom class when bound:
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*
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* {@sample development/samples/ApiDemos/src/com/example/android/apis/app/LocalService.java
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* service}
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*
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* <p>With that done, one can now write client code that directly accesses the
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* running service, such as:
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*
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* {@sample development/samples/ApiDemos/src/com/example/android/apis/app/LocalServiceActivities.java
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* bind}
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*
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* <a name="RemoteMessengerServiceSample"></a>
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* <h3>Remote Messenger Service Sample</h3>
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*
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* <p>If you need to be able to write a Service that can perform complicated
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* communication with clients in remote processes (beyond simply the use of
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* {@link Context#startService(Intent) Context.startService} to send
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* commands to it), then you can use the {@link android.os.Messenger} class
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* instead of writing full AIDL files.
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*
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* <p>An example of a Service that uses Messenger as its client interface
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* is shown here. First is the Service itself, publishing a Messenger to
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* an internal Handler when bound:
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*
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* {@sample development/samples/ApiDemos/src/com/example/android/apis/app/MessengerService.java
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* service}
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*
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* <p>If we want to make this service run in a remote process (instead of the
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* standard one for its .apk), we can use <code>android:process</code> in its
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* manifest tag to specify one:
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*
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* {@sample development/samples/ApiDemos/AndroidManifest.xml remote_service_declaration}
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*
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* <p>Note that the name "remote" chosen here is arbitrary, and you can use
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* other names if you want additional processes. The ':' prefix appends the
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* name to your package's standard process name.
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*
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* <p>With that done, clients can now bind to the service and send messages
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* to it. Note that this allows clients to register with it to receive
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* messages back as well:
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*
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* {@sample development/samples/ApiDemos/src/com/example/android/apis/app/MessengerServiceActivities.java
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* bind}
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*/
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public abstract class Service extends ContextWrapper implements ComponentCallbacks {
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private static final String TAG = "Service";
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public Service() {
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super(null);
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}
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/** Return the application that owns this service. */
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public final Application getApplication() {
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return mApplication;
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}
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/**
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* Called by the system when the service is first created. Do not call this method directly.
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*/
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public void onCreate() {
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}
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/**
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* @deprecated Implement {@link #onStartCommand(Intent, int, int)} instead.
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*/
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@Deprecated
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public void onStart(Intent intent, int startId) {
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}
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/**
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* Bits returned by {@link #onStartCommand} describing how to continue
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* the service if it is killed. May be {@link #START_STICKY},
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* {@link #START_NOT_STICKY}, {@link #START_REDELIVER_INTENT},
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* or {@link #START_STICKY_COMPATIBILITY}.
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*/
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public static final int START_CONTINUATION_MASK = 0xf;
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/**
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* Constant to return from {@link #onStartCommand}: compatibility
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* version of {@link #START_STICKY} that does not guarantee that
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* {@link #onStartCommand} will be called again after being killed.
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*/
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public static final int START_STICKY_COMPATIBILITY = 0;
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/**
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* Constant to return from {@link #onStartCommand}: if this service's
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* process is killed while it is started (after returning from
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* {@link #onStartCommand}), then leave it in the started state but
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* don't retain this delivered intent. Later the system will try to
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* re-create the service. Because it is in the started state, it will
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* guarantee to call {@link #onStartCommand} after creating the new
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* service instance; if there are not any pending start commands to be
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* delivered to the service, it will be called with a null intent
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* object, so you must take care to check for this.
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*
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* <p>This mode makes sense for things that will be explicitly started
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* and stopped to run for arbitrary periods of time, such as a service
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* performing background music playback.
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*/
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public static final int START_STICKY = 1;
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/**
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* Constant to return from {@link #onStartCommand}: if this service's
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* process is killed while it is started (after returning from
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* {@link #onStartCommand}), and there are no new start intents to
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* deliver to it, then take the service out of the started state and
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* don't recreate until a future explicit call to
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* {@link Context#startService Context.startService(Intent)}. The
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* service will not receive a {@link #onStartCommand(Intent, int, int)}
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* call with a null Intent because it will not be re-started if there
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* are no pending Intents to deliver.
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*
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* <p>This mode makes sense for things that want to do some work as a
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* result of being started, but can be stopped when under memory pressure
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* and will explicit start themselves again later to do more work. An
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* example of such a service would be one that polls for data from
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* a server: it could schedule an alarm to poll every N minutes by having
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* the alarm start its service. When its {@link #onStartCommand} is
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* called from the alarm, it schedules a new alarm for N minutes later,
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* and spawns a thread to do its networking. If its process is killed
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* while doing that check, the service will not be restarted until the
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* alarm goes off.
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*/
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public static final int START_NOT_STICKY = 2;
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/**
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* Constant to return from {@link #onStartCommand}: if this service's
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* process is killed while it is started (after returning from
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* {@link #onStartCommand}), then it will be scheduled for a restart
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* and the last delivered Intent re-delivered to it again via
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* {@link #onStartCommand}. This Intent will remain scheduled for
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* redelivery until the service calls {@link #stopSelf(int)} with the
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* start ID provided to {@link #onStartCommand}. The
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* service will not receive a {@link #onStartCommand(Intent, int, int)}
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* call with a null Intent because it will will only be re-started if
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* it is not finished processing all Intents sent to it (and any such
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* pending events will be delivered at the point of restart).
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*/
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public static final int START_REDELIVER_INTENT = 3;
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/**
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* This flag is set in {@link #onStartCommand} if the Intent is a
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* re-delivery of a previously delivered intent, because the service
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* had previously returned {@link #START_REDELIVER_INTENT} but had been
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* killed before calling {@link #stopSelf(int)} for that Intent.
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*/
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public static final int START_FLAG_REDELIVERY = 0x0001;
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/**
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* This flag is set in {@link #onStartCommand} if the Intent is a
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* a retry because the original attempt never got to or returned from
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* {@link #onStartCommand(Intent, int, int)}.
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*/
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public static final int START_FLAG_RETRY = 0x0002;
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/**
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* Called by the system every time a client explicitly starts the service by calling
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* {@link android.content.Context#startService}, providing the arguments it supplied and a
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* unique integer token representing the start request. Do not call this method directly.
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*
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* <p>For backwards compatibility, the default implementation calls
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* {@link #onStart} and returns either {@link #START_STICKY}
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* or {@link #START_STICKY_COMPATIBILITY}.
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*
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* <p>If you need your application to run on platform versions prior to API
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* level 5, you can use the following model to handle the older {@link #onStart}
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* callback in that case. The <code>handleCommand</code> method is implemented by
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* you as appropriate:
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*
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* {@sample development/samples/ApiDemos/src/com/example/android/apis/app/ForegroundService.java
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* start_compatibility}
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*
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* <p class="caution">Note that the system calls this on your
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* service's main thread. A service's main thread is the same
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* thread where UI operations take place for Activities running in the
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* same process. You should always avoid stalling the main
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* thread's event loop. When doing long-running operations,
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* network calls, or heavy disk I/O, you should kick off a new
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* thread, or use {@link android.os.AsyncTask}.</p>
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*
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* @param intent The Intent supplied to {@link android.content.Context#startService},
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* as given. This may be null if the service is being restarted after
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* its process has gone away, and it had previously returned anything
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* except {@link #START_STICKY_COMPATIBILITY}.
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* @param flags Additional data about this start request. Currently either
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* 0, {@link #START_FLAG_REDELIVERY}, or {@link #START_FLAG_RETRY}.
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* @param startId A unique integer representing this specific request to
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* start. Use with {@link #stopSelfResult(int)}.
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*
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* @return The return value indicates what semantics the system should
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* use for the service's current started state. It may be one of the
|
|
* constants associated with the {@link #START_CONTINUATION_MASK} bits.
|
|
*
|
|
* @see #stopSelfResult(int)
|
|
*/
|
|
public int onStartCommand(Intent intent, int flags, int startId) {
|
|
onStart(intent, startId);
|
|
return mStartCompatibility ? START_STICKY_COMPATIBILITY : START_STICKY;
|
|
}
|
|
|
|
/**
|
|
* Called by the system to notify a Service that it is no longer used and is being removed. The
|
|
* service should clean up an resources it holds (threads, registered
|
|
* receivers, etc) at this point. Upon return, there will be no more calls
|
|
* in to this Service object and it is effectively dead. Do not call this method directly.
|
|
*/
|
|
public void onDestroy() {
|
|
}
|
|
|
|
public void onConfigurationChanged(Configuration newConfig) {
|
|
}
|
|
|
|
public void onLowMemory() {
|
|
}
|
|
|
|
/**
|
|
* Return the communication channel to the service. May return null if
|
|
* clients can not bind to the service. The returned
|
|
* {@link android.os.IBinder} is usually for a complex interface
|
|
* that has been <a href="{@docRoot}guide/developing/tools/aidl.html">described using
|
|
* aidl</a>.
|
|
*
|
|
* <p><em>Note that unlike other application components, calls on to the
|
|
* IBinder interface returned here may not happen on the main thread
|
|
* of the process</em>. More information about this can be found
|
|
* in <a href="{@docRoot}guide/topics/fundamentals.html#procthread">Application Fundamentals:
|
|
* Processes and Threads</a>.</p>
|
|
*
|
|
* @param intent The Intent that was used to bind to this service,
|
|
* as given to {@link android.content.Context#bindService
|
|
* Context.bindService}. Note that any extras that were included with
|
|
* the Intent at that point will <em>not</em> be seen here.
|
|
*
|
|
* @return Return an IBinder through which clients can call on to the
|
|
* service.
|
|
*/
|
|
public abstract IBinder onBind(Intent intent);
|
|
|
|
/**
|
|
* Called when all clients have disconnected from a particular interface
|
|
* published by the service. The default implementation does nothing and
|
|
* returns false.
|
|
*
|
|
* @param intent The Intent that was used to bind to this service,
|
|
* as given to {@link android.content.Context#bindService
|
|
* Context.bindService}. Note that any extras that were included with
|
|
* the Intent at that point will <em>not</em> be seen here.
|
|
*
|
|
* @return Return true if you would like to have the service's
|
|
* {@link #onRebind} method later called when new clients bind to it.
|
|
*/
|
|
public boolean onUnbind(Intent intent) {
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Called when new clients have connected to the service, after it had
|
|
* previously been notified that all had disconnected in its
|
|
* {@link #onUnbind}. This will only be called if the implementation
|
|
* of {@link #onUnbind} was overridden to return true.
|
|
*
|
|
* @param intent The Intent that was used to bind to this service,
|
|
* as given to {@link android.content.Context#bindService
|
|
* Context.bindService}. Note that any extras that were included with
|
|
* the Intent at that point will <em>not</em> be seen here.
|
|
*/
|
|
public void onRebind(Intent intent) {
|
|
}
|
|
|
|
/**
|
|
* Stop the service, if it was previously started. This is the same as
|
|
* calling {@link android.content.Context#stopService} for this particular service.
|
|
*
|
|
* @see #stopSelfResult(int)
|
|
*/
|
|
public final void stopSelf() {
|
|
stopSelf(-1);
|
|
}
|
|
|
|
/**
|
|
* Old version of {@link #stopSelfResult} that doesn't return a result.
|
|
*
|
|
* @see #stopSelfResult
|
|
*/
|
|
public final void stopSelf(int startId) {
|
|
if (mActivityManager == null) {
|
|
return;
|
|
}
|
|
try {
|
|
mActivityManager.stopServiceToken(
|
|
new ComponentName(this, mClassName), mToken, startId);
|
|
} catch (RemoteException ex) {
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Stop the service if the most recent time it was started was
|
|
* <var>startId</var>. This is the same as calling {@link
|
|
* android.content.Context#stopService} for this particular service but allows you to
|
|
* safely avoid stopping if there is a start request from a client that you
|
|
* haven't yet seen in {@link #onStart}.
|
|
*
|
|
* <p><em>Be careful about ordering of your calls to this function.</em>.
|
|
* If you call this function with the most-recently received ID before
|
|
* you have called it for previously received IDs, the service will be
|
|
* immediately stopped anyway. If you may end up processing IDs out
|
|
* of order (such as by dispatching them on separate threads), then you
|
|
* are responsible for stopping them in the same order you received them.</p>
|
|
*
|
|
* @param startId The most recent start identifier received in {@link
|
|
* #onStart}.
|
|
* @return Returns true if the startId matches the last start request
|
|
* and the service will be stopped, else false.
|
|
*
|
|
* @see #stopSelf()
|
|
*/
|
|
public final boolean stopSelfResult(int startId) {
|
|
if (mActivityManager == null) {
|
|
return false;
|
|
}
|
|
try {
|
|
return mActivityManager.stopServiceToken(
|
|
new ComponentName(this, mClassName), mToken, startId);
|
|
} catch (RemoteException ex) {
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* @deprecated This is a now a no-op, use
|
|
* {@link #startForeground(int, Notification)} instead. This method
|
|
* has been turned into a no-op rather than simply being deprecated
|
|
* because analysis of numerous poorly behaving devices has shown that
|
|
* increasingly often the trouble is being caused in part by applications
|
|
* that are abusing it. Thus, given a choice between introducing
|
|
* problems in existing applications using this API (by allowing them to
|
|
* be killed when they would like to avoid it), vs allowing the performance
|
|
* of the entire system to be decreased, this method was deemed less
|
|
* important.
|
|
*/
|
|
@Deprecated
|
|
public final void setForeground(boolean isForeground) {
|
|
Log.w(TAG, "setForeground: ignoring old API call on " + getClass().getName());
|
|
}
|
|
|
|
/**
|
|
* Make this service run in the foreground, supplying the ongoing
|
|
* notification to be shown to the user while in this state.
|
|
* By default services are background, meaning that if the system needs to
|
|
* kill them to reclaim more memory (such as to display a large page in a
|
|
* web browser), they can be killed without too much harm. You can set this
|
|
* flag if killing your service would be disruptive to the user, such as
|
|
* if your service is performing background music playback, so the user
|
|
* would notice if their music stopped playing.
|
|
*
|
|
* <p>If you need your application to run on platform versions prior to API
|
|
* level 5, you can use the following model to call the the older {@link #setForeground}
|
|
* or this modern method as appropriate:
|
|
*
|
|
* {@sample development/samples/ApiDemos/src/com/example/android/apis/app/ForegroundService.java
|
|
* foreground_compatibility}
|
|
*
|
|
* @param id The identifier for this notification as per
|
|
* {@link NotificationManager#notify(int, Notification)
|
|
* NotificationManager.notify(int, Notification)}.
|
|
* @param notification The Notification to be displayed.
|
|
*
|
|
* @see #stopForeground(boolean)
|
|
*/
|
|
public final void startForeground(int id, Notification notification) {
|
|
try {
|
|
mActivityManager.setServiceForeground(
|
|
new ComponentName(this, mClassName), mToken, id,
|
|
notification, true);
|
|
} catch (RemoteException ex) {
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Remove this service from foreground state, allowing it to be killed if
|
|
* more memory is needed.
|
|
* @param removeNotification If true, the notification previously provided
|
|
* to {@link #startForeground} will be removed. Otherwise it will remain
|
|
* until a later call removes it (or the service is destroyed).
|
|
* @see #startForeground(int, Notification)
|
|
*/
|
|
public final void stopForeground(boolean removeNotification) {
|
|
try {
|
|
mActivityManager.setServiceForeground(
|
|
new ComponentName(this, mClassName), mToken, 0, null,
|
|
removeNotification);
|
|
} catch (RemoteException ex) {
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Print the Service's state into the given stream. This gets invoked if
|
|
* you run "adb shell dumpsys activity service <yourservicename>".
|
|
* This is distinct from "dumpsys <servicename>", which only works for
|
|
* named system services and which invokes the {@link IBinder#dump} method
|
|
* on the {@link IBinder} interface registered with ServiceManager.
|
|
*
|
|
* @param fd The raw file descriptor that the dump is being sent to.
|
|
* @param writer The PrintWriter to which you should dump your state. This will be
|
|
* closed for you after you return.
|
|
* @param args additional arguments to the dump request.
|
|
*/
|
|
protected void dump(FileDescriptor fd, PrintWriter writer, String[] args) {
|
|
writer.println("nothing to dump");
|
|
}
|
|
|
|
@Override
|
|
protected void finalize() throws Throwable {
|
|
super.finalize();
|
|
//Log.i("Service", "Finalizing Service: " + this);
|
|
}
|
|
|
|
// ------------------ Internal API ------------------
|
|
|
|
/**
|
|
* @hide
|
|
*/
|
|
public final void attach(
|
|
Context context,
|
|
ActivityThread thread, String className, IBinder token,
|
|
Application application, Object activityManager) {
|
|
attachBaseContext(context);
|
|
mThread = thread; // NOTE: unused - remove?
|
|
mClassName = className;
|
|
mToken = token;
|
|
mApplication = application;
|
|
mActivityManager = (IActivityManager)activityManager;
|
|
mStartCompatibility = getApplicationInfo().targetSdkVersion
|
|
< Build.VERSION_CODES.ECLAIR;
|
|
}
|
|
|
|
final String getClassName() {
|
|
return mClassName;
|
|
}
|
|
|
|
// set by the thread after the constructor and before onCreate(Bundle icicle) is called.
|
|
private ActivityThread mThread = null;
|
|
private String mClassName = null;
|
|
private IBinder mToken = null;
|
|
private Application mApplication = null;
|
|
private IActivityManager mActivityManager = null;
|
|
private boolean mStartCompatibility = false;
|
|
}
|