Question

我是Android的新手，对服务和广播接收器知之甚少。我正在开发一个应用程序，当我到达某个特定位置时，我希望我的手机进入静音模式。我希望广播接收器在到达该位置时启动服务。我的问题是，当应用程序关闭时，广播接收器似乎无法运行。当应用程序关闭时，如何让广播接收器运行并调用服务？我的代码如下。

GPSTracker.java

公共类GPSTracker扩展服务实现LocationListener {

private final Context mContext;

// flag for GPS status
boolean isGPSEnabled = false;

// flag for network status
boolean isNetworkEnabled = false;

// flag for GPS status
boolean canGetLocation = false;

Location location; // location
double latitude; // latitude
double longitude; // longitude

// The minimum distance to change Updates in meters
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; // 10 meters

// The minimum time between updates in milliseconds
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1; // 1 minute

// Declaring a Location Manager
protected LocationManager locationManager;

public GPSTracker(Context context) {
    this.mContext = context;
    getLocation();
}

public Location getLocation() {
    try {
        locationManager = (LocationManager) mContext
                .getSystemService(LOCATION_SERVICE);

        // getting GPS status
        isGPSEnabled = locationManager
                .isProviderEnabled(LocationManager.GPS_PROVIDER);

        // getting network status
        isNetworkEnabled = locationManager
                .isProviderEnabled(LocationManager.NETWORK_PROVIDER);

        if (!isGPSEnabled && !isNetworkEnabled) {
            // no network provider is enabled
        } else {
            this.canGetLocation = true;
            if (isNetworkEnabled) {
                locationManager.requestLocationUpdates(
                        LocationManager.NETWORK_PROVIDER,
                        MIN_TIME_BW_UPDATES,
                        MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                Log.d("Network", "Network");
                if (locationManager != null) {
                    location = locationManager
                            .getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
                    if (location != null) {
                        latitude = location.getLatitude();
                        longitude = location.getLongitude();
                    }
                }
            }
            // if GPS Enabled get lat/long using GPS Services
            if (isGPSEnabled) {
                if (location == null) {
                    locationManager.requestLocationUpdates(
                            LocationManager.GPS_PROVIDER,
                            MIN_TIME_BW_UPDATES,
                            MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                    Log.d("GPS Enabled", "GPS Enabled");
                    if (locationManager != null) {
                        location = locationManager
                                .getLastKnownLocation(LocationManager.GPS_PROVIDER);
                        if (location != null) {
                            latitude = location.getLatitude();
                            longitude = location.getLongitude();
                        }
                    }
                }
            }
        }

    } catch (Exception e) {
        e.printStackTrace();
    }

    return location;
}

/**
 * Stop using GPS listener
 * Calling this function will stop using GPS in your app
 * */
public void stopUsingGPS(){
    if(locationManager != null){
        locationManager.removeUpdates(GPSTracker.this);
    }       
}

/**
 * Function to get latitude
 * */
public double getLatitude(){
    if(location != null){
        latitude = location.getLatitude();
    }

    // return latitude
    return latitude;
}

/**
 * Function to get longitude
 * */
public double getLongitude(){
    if(location != null){
        longitude = location.getLongitude();
    }

    // return longitude
    return longitude;
}

/**
 * Function to check GPS/wifi enabled
 * @return boolean
 * */
public boolean canGetLocation() {
    return this.canGetLocation;
}

/**
 * Function to show settings alert dialog
 * On pressing Settings button will lauch Settings Options
 * */
public void showSettingsAlert(){
    AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);

    // Setting Dialog Title
    alertDialog.setTitle("GPS is settings");

    // Setting Dialog Message
    alertDialog.setMessage("GPS is not enabled. Do you want to go to settings menu?");

    // On pressing Settings button
    alertDialog.setPositiveButton("Settings", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog,int which) {
            Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
            mContext.startActivity(intent);
        }
    });

    // on pressing cancel button
    alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int which) {
        dialog.cancel();
        }
    });

    // Showing Alert Message
    alertDialog.show();
}

@Override
public void onLocationChanged(Location location) {
    latitude = location.getLatitude();
    longitude = location.getLongitude();

}

@Override
public void onProviderDisabled(String provider) {
}

@Override
public void onProviderEnabled(String provider) {
}

@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}

@Override
public IBinder onBind(Intent arg0) {
    return null;
}

}

BootUpReceiver.java

public class BootUpReceiver extends BroadcastReceiver{
GPSTracker g;
@Override
public void onReceive(Context context, Intent intent) {
    // TODO Auto-generated method stub
    Intent i = new Intent(context,GPSTracker.class);
    context.startService(i);

} }

清单文件

   <receiver android:permission="android.permission.ACCESS_COARSE_LOCATION" android:name="BootUpReceiver">
   <intent-filter>

                        <action android:name="android.location.LocationManager.KEY_LOCATION_CHANGED" />
              <action android:name="android.location.PROVIDERS_CHANGED" />
              <action android:name="android.intent.action.TIME_TICK"/>
        </intent-filter>
    </receiver>

清单

      <receiver android:name=".BootUpReceiver"
    android:enabled="true" android:permission="android.permission.SET_TIME">
    <intent-filter>

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

Answer 1

我想把它放在评论中，但它几乎难以辨认。你的代码相当混乱，但我们都必须从某个地方开始。您需要更改清单，格式不正确。看起来应该是这样的：

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.appname"
android:versionCode="1"
android:versionName="1.0" >

<uses-sdk
    android:minSdkVersion="8"
    android:targetSdkVersion="18" />

<!-- PERMISSIONS -->
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />

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

    <!-- RECEIVERS -->
    <receiver android:name=".BootUpReceiver"
        android:enabled="true" >
        <intent-filter>
             <action android:name="android.intent.action.ACTION_BOOT_COMPLETED" />
             <action android:name="android.intent.action.BOOT_COMPLETED" />
             <action android:name="com.htc.intent.action.QUICKBOOT_POWERON" />
        </intent-filter>
    </receiver>

    <!-- SERVICES -->
    <service
        android:enabled="true"
        android:name=".GPSTracker" />

    <!-- ACTIVITIES -->
    <activity
        android:name="com.example.appname.LaunchActivity"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
</application>

请注意权限以及我添加它们的方式，以及服务和接收器。然后，您需要确保正确设置广播接收器。

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.widget.Toast;

public class BootUpReceiver extends BroadcastReceiver{

    @Override
    public void onReceive(Context c, Intent i) {
        Intent gpsIntent = new Intent(c, GPSTracker.class); 


        // Add putExtras() or look at parceables to see if there is anything we need to do here

       Toast.makeText(c, "Our broadcast receiver was hit!", Toast.LENGTH_LONG).show();

        // Start the activity (by utilizing the passed context)
        gpsIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        c.getApplicationContext().startService(gpsIntent); 

    }

}

然后您的GPSTracker课程似乎正确实施。

即使在Android中关闭应用程序后，如何使用广播接收器启动服务？

1 个答案: