Question

我希望服务始终在后台运行，以便我可以随时收到通知，也可以在通过删除后从任务管理器中删除应用程序

Answer 1

当您从任务管理器中删除应用程序时，它会终止进程并且您的服务正在该进程中运行。您必须在不同的过程中运行服务。你可以在清单文件中做到这一点

<service 
    . . .
         android:process="string" >
</service>

Answer 2

服务本身在后台运行，如果您关闭应用程序并不重要。

如果您想了解更多详情

https://developer.android.com/guide/components/services.html

Answer 3

<强> MainActivity.java

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button but_start = (Button) findViewById(R.id.but_Start);
        but_start.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent intent = new Intent(getApplicationContext(),
                        MyService.class);
                startService(intent);
            }
        });
    }
}

<强> MyService.java

public class MyService extends Service {
    @Override
    public void onStart(Intent intent, int startId) {
        // TODO Auto-generated method stub
        super.onStart(intent, startId);
        Toast.makeText(getApplicationContext(), "Service Started in" +
                " a Different " +
                "Process", Toast.LENGTH_LONG).show();
        //stopSelf();//force service to a stop.
    }

    @Override
    public IBinder onBind(Intent intent) {
        // TODO Auto-generated method stub
        return null;
    }
}

<强> activity_main.xml中

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <Button
        android:id="@+id/but_Start"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentRight="true"
        android:layout_centerVertical="true"
        android:text="Start Service" />

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:layout_marginTop="56dp"
        android:text= "Start Service in a Different Process"
        android:textAppearance="?android:attr/textAppearanceLarge" />

</RelativeLayout>

<强>的AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.start_service_diff_process"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="17" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.example.start_service_diff_process.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <service
            android:name=".MyService"
            android:enabled="true"
            android:process=":my_process" />
    </application>

</manifest>

在所有Android设备中从后台查杀后运行服务

3 个答案: