Java Android：在后台运行应用程序的问题

我试图让我的GPS在后台运行，这样它可以在我做其他事情时为我提供关于我在哪里的新信息

但每次我运行应用程序时，它都会崩溃。错误要求我使用

Looper.prepare（）

，但我如何使用GPS来实现这一点

public class LocationLoggerService extends Service implements LocationListener {

Location location;

String towers;
static final int uniqueID = 1394885;
Thread runner;
boolean keepRunning;

public LocationManager locationManager;

@Override
public IBinder onBind(Intent intent) {
    return null;
}

@Override
public void onCreate() {

    keepRunning = true;

    runner = new Thread(null, new Runnable() {
        public void run() {
            startGps();
        }
    });
    runner.start();
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    // this service will run until we stop it

    return START_STICKY;
}

@Override
public void onLocationChanged(Location location) {

    location = locationManager.getLastKnownLocation(towers);

    String hey1 = Double.toString(location.getLatitude());
    String hey2 = Double.toString(location.getLongitude());

    Toast.makeText(this,
            "TEST onLocationChanged:" + "Lat: " + hey1 + "Long: " + hey2,

            Toast.LENGTH_LONG).show();
}

@Override
public void onProviderEnabled(String s) {
}

@Override
public void onProviderDisabled(String s) {
}

@Override
public void onStatusChanged(String s, int i, Bundle b) {
}

@Override
public void onDestroy() {
    super.onDestroy();
    Toast.makeText(this, "MyAlarmService.onDestroy()", Toast.LENGTH_LONG)
            .show();

}

public void startGps() {
    locationManager = (LocationManager) this
            .getSystemService(Context.LOCATION_SERVICE);
    locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,
            2000, 0, this);

    location = locationManager.getLastKnownLocation(towers);

    String hey1 = Double.toString(location.getLatitude());
    String hey2 = Double.toString(location.getLongitude());

    Toast.makeText(this, "StartGPS: Lat: " + hey1 + "Long: " + hey2,
            Toast.LENGTH_LONG).show();

}


}

我的清单具有以下权限，如下所示：

<uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.VIBRATE" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_GPS" />

<service
            android:name="LocationLoggerService"
            android:enabled="true"
            android:exported="false"
            android:label="LocationLoggerService" />

FATAL EXCEPTION: Thread-819
java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
at android.os.Handler.<init>(Handler.java:121)
at android.location.LocationManager$ListenerTransport$1.<init>(LocationManager.java:209)
at android.location.LocationManager$ListenerTransport.<init>(LocationManager.java:209)
at android.location.LocationManager._requestLocationUpdates(LocationManager.java:687)
at android.location.LocationManager.requestLocationUpdates(LocationManager.java:512)
at com.example.rememberforme.LocationLoggerService.startGps(LocationLoggerService.java:81)
at com.example.rememberforme.LocationLoggerService$1.run(LocationLoggerService.java:38)
at java.lang.Thread.run(Thread.java:856)

我在logcat中得到此错误，如下所示：

<uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.VIBRATE" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_GPS" />

<service
            android:name="LocationLoggerService"
            android:enabled="true"
            android:exported="false"
            android:label="LocationLoggerService" />

FATAL EXCEPTION: Thread-819
java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
at android.os.Handler.<init>(Handler.java:121)
at android.location.LocationManager$ListenerTransport$1.<init>(LocationManager.java:209)
at android.location.LocationManager$ListenerTransport.<init>(LocationManager.java:209)
at android.location.LocationManager._requestLocationUpdates(LocationManager.java:687)
at android.location.LocationManager.requestLocationUpdates(LocationManager.java:512)
at com.example.rememberforme.LocationLoggerService.startGps(LocationLoggerService.java:81)
at com.example.rememberforme.LocationLoggerService$1.run(LocationLoggerService.java:38)
at java.lang.Thread.run(Thread.java:856)

致命异常：线程819
java.lang.RuntimeException:无法在未调用Looper.prepare（）的线程内创建处理程序
android.os.Handler.（Handler.java:121）
在android.location.LocationManager$ListenerTransport$1。（LocationManager.java:209）
在android.location.LocationManager$ListenerTransport。（LocationManager.java:209）
在android.location.LocationManager.\u请求LocationUpdate（LocationManager.java:687）
位于android.location.LocationManager.RequestLocationUpdate（LocationManager.java:512）
在com.example.rememberforme.LocationLoggerService.startGps（LocationLoggerService.java:81）
在com.example.rememberforme.LocationLoggerService$1.run（LocationLoggerService.java:38）
运行（Thread.java:856）

嘿

我发现您缺少服务的onCommandStart方法

@Override
public int onStartCommand(Intent intent, int flags, int startId)
{
    //this service will run until we stop it

    return START_STICKY;
}

您是否在清单文件中添加了所需的所有权限？ 我不确定您需要哪一个，但其中一个或多个就可以了：

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_GPS"/>

LogCat中的错误是什么？LogCat与您的应用程序无关-请附上适当的LogCat，其中显示您的应用程序正在运行！FWIW，这甚至不是一个错误-这是来自本地二进制NDK编译的GPS处理程序…OP：请重新编辑您的问题，不要在这些评论中放入1行日志。。。确保包含尽可能多的行，以便我们可以推断错误在哪里！我刚刚更新了我的问题@T0MM13b问题是在

startGPS

中调用

Toast

的线程是导致崩溃的原因。您需要实现一种机制，例如

runOnUiThread

，它将

Runnable

作为参数，在这种机制中，UI可以在自己的线程中制作Toast，或者实现一个处理程序（从UI线程创建）然后从线程

startGps

中将消息传递给处理程序，弹出

Toast

通知。我刚刚更新了代码。但我遇到了一个新问题。Looper.prepare（）