java - Android IntentService 无法在开机时启动

Question

我试图在设备启动时启动 IntentService，但我一直收到此错误:

10-11 02:03:39.009 2675-2675/? E/AndroidRuntime: FATAL EXCEPTION: main
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime: Process: fi.tut.cs.social.proximeety, PID: 2675
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime: java.lang.RuntimeException: Unable to start service fi.tut.cs.social.proximeety.N2YIntentService@2aab3021 with Intent { cmp=fi.tut.cs.social.proximeety/.N2YIntentService (has extras) }: java.lang.NullPointerException: Attempt to invoke virtual method 'android.os.Message android.app.IntentService$ServiceHandler.obtainMessage()' on a null object reference
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:2911)
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at android.app.ActivityThread.access$2100(ActivityThread.java:151)
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1401)
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at android.os.Handler.dispatchMessage(Handler.java:102)
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at android.os.Looper.loop(Looper.java:135)
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at android.app.ActivityThread.main(ActivityThread.java:5254)
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method)
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:372)
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:  Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.os.Message android.app.IntentService$ServiceHandler.obtainMessage()' on a null object reference
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at android.app.IntentService.onStart(IntentService.java:116)
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at android.app.IntentService.onStartCommand(IntentService.java:130)
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:2894)
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at android.app.ActivityThread.access$2100(ActivityThread.java:151) 
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1401) 
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at android.os.Handler.dispatchMessage(Handler.java:102) 
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at android.os.Looper.loop(Looper.java:135) 
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at android.app.ActivityThread.main(ActivityThread.java:5254) 
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method) 
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:372) 
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903) 
10-11 02:03:39.009 2675-2675/? E/AndroidRuntime:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698) 

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="fi.tut.cs.social.proximeety" >

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.BLUETOOTH" />
    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
    <uses-permission android:name="android.permission.VIBRATE"/>
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
    <uses-permission android:name="android.permission.WAKE_LOCK" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/logo"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >

        <activity
            android:name=".MainActivity"
            android:label="@string/app_name"
            android:windowSoftInputMode="adjustPan"
            android:screenOrientation="portrait"
            android:configChanges="keyboardHidden|orientation|screenSize"
            >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <receiver
            android:name=".BootBroadcastReceiver">
            <intent-filter>
                <action android:name="android.intent.action.BOOT_COMPLETED" />
            </intent-filter>
        </receiver>

        <service
            android:name=".N2YIntentService"
            android:exported="true"/>
    </application>

</manifest>

BootBroadcastReceiver.java

package fi.tut.cs.social.proximeety;

import android.content.Context;
import android.content.Intent;
import android.support.v4.content.WakefulBroadcastReceiver;
import android.util.Log;

public class BootBroadcastReceiver extends WakefulBroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {

        // Launch the specified service when this message is received
        Intent startServiceIntent = new Intent(context, N2YIntentService.class);
        context.startService(startServiceIntent);
    }
}

N2YIntentService.java

package fi.tut.cs.social.proximeety;

import android.app.IntentService;
import android.content.Intent;
import android.support.v4.content.WakefulBroadcastReceiver;
import android.util.Log;

public class N2YIntentService extends IntentService{
    final String TAG = "N2YIntentService";


    // Default constructor
    public N2YIntentService() {
        super("N2YIntentService");
        Log.d(TAG, "Default Constructor");
    }

    @Override
    public void onCreate() {
        Log.d(TAG, "onCreate()");
    }

    @Override
    public void onHandleIntent(Intent intent) {
        Log.d(TAG, "onHandleIntent()");

        WakefulBroadcastReceiver.completeWakefulIntent(intent);
    }
}

如果您能发现我的代码有问题，我将不胜感激。 提前致谢!

Answer 1

在 N2YIntentService 中，您应该在 onCreate 方法中调用 super.onCreate()。