我正在尝试将服务绑定到我的活动并从中获取位置值。
我有以下服务：
GPSService.java
public class GPSService extends SensorElement {
// Binder given to clients
private final IBinder mBinder = new LocalBinder();
/**
* Class used for the client Binder. Because we know this service always
* runs in the same process as its clients, we don't need to deal with IPC.
*/
public class LocalBinder extends Binder {
public GPSService getService() {
// Return this instance of GPSService so clients can call public
// methods
return GPSService.this;
}
}
private static final String TAG = "GPSServive";
private LocationManager mLocationManager = null;
private static final int LOCATION_INTERVAL = 1000;
private static final float LOCATION_DISTANCE = 10f;
private Location location;
private boolean canGetLocation;
private double latitude;
private double longitude;
private double accuracy;
private long timestamp;
public SensorType type = SensorType.SOFTWARE_SENSOR;
public SensorName name = SensorName.GPS_SENSOR;
private class LocationListener implements android.location.LocationListener {
Location mLastLocation;
public LocationListener(String provider) {
Log.e(TAG, "LocationListener " + provider);
mLastLocation = new Location(provider);
}
@Override
public void onLocationChanged(Location location) {
Log.e(TAG, "onLocationChanged: " + location);
mLastLocation.set(location);
}
@Override
public void onProviderDisabled(String provider) {
Log.e(TAG, "onProviderDisabled: " + provider);
}
@Override
public void onProviderEnabled(String provider) {
Log.e(TAG, "onProviderEnabled: " + provider);
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
Log.e(TAG, "onStatusChanged: " + provider);
}
}
LocationListener[] mLocationListeners = new LocationListener[] {
new LocationListener(LocationManager.GPS_PROVIDER),
new LocationListener(LocationManager.NETWORK_PROVIDER) };
@Override
public IBinder onBind(Intent arg0) {
return mBinder;
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.e(TAG, "onStartCommand");
super.onStartCommand(intent, flags, startId);
return START_STICKY;
}
@Override
public void onCreate() {
Log.e(TAG, "onCreate");
initializeLocationManager();
if (!isNetworkAvailable() && !isGPSAvailable()) {
// no network provider is enabled
setCanGetLocation(false);
} else if (isNetworkAvailable()){
setCanGetLocation(true);
try {
mLocationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER, LOCATION_INTERVAL,
LOCATION_DISTANCE, mLocationListeners[1]);
location = mLocationManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
accuracy = location.getAccuracy();
timestamp = System.currentTimeMillis();
}
} catch (java.lang.SecurityException ex) {
Log.i(TAG, "fail to request location update, ignore", ex);
} catch (IllegalArgumentException ex) {
Log.d(TAG, "gps provider does not exist " + ex.getMessage());
}
} else if (isGPSAvailable()) {
setCanGetLocation(true);
try {
mLocationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER, LOCATION_INTERVAL,
LOCATION_DISTANCE, mLocationListeners[0]);
location = mLocationManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
accuracy = location.getAccuracy();
timestamp = System.currentTimeMillis();
}
} catch (java.lang.SecurityException ex) {
Log.i(TAG, "fail to request location update, ignore", ex);
} catch (IllegalArgumentException ex) {
Log.d(TAG,
"network provider does not exist, " + ex.getMessage());
}
}
}
@Override
public void onDestroy() {
Log.e(TAG, "onDestroy");
super.onDestroy();
if (mLocationManager != null) {
for (int i = 0; i < mLocationListeners.length; i++) {
try {
mLocationManager.removeUpdates(mLocationListeners[i]);
} catch (Exception ex) {
Log.i(TAG, "fail to remove location listners, ignore", ex);
}
}
}
}
private void initializeLocationManager() {
Log.e(TAG, "initializeLocationManager");
if (mLocationManager == null) {
mLocationManager = (LocationManager) getApplicationContext()
.getSystemService(Context.LOCATION_SERVICE);
}
}
private boolean isNetworkAvailable() {
return mLocationManager
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
}
private boolean isGPSAvailable() {
return mLocationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
}
public double getLatitude() {
return latitude;
}
public double getLongitude() {
return longitude;
}
public double getAccuracy() {
return accuracy;
}
public long getTimestamp() {
return timestamp;
}
public SensorType getType() {
return type;
}
public void setType(SensorType type) {
this.type = type;
}
public SensorName getName() {
return name;
}
public void setName(SensorName name) {
this.name = name;
}
public boolean isCanGetLocation() {
return canGetLocation;
}
public void setCanGetLocation(boolean canGetLocation) {
this.canGetLocation = canGetLocation;
}
}
这是 GPSService 扩展的抽象类。这样做的目标是拥有可以概括传感器、gps 传感器、加速度计传感器、任何传感器的东西。
SensorElement.java
public abstract class SensorElement extends Service{
protected SensorType type;
protected SensorName name;
@Override
public abstract IBinder onBind(Intent arg0);
@Override
public int onStartCommand(Intent intent, int flags, int startId){
return super.onStartCommand(intent, flags, startId);
}
@Override
public abstract void onCreate();
@Override
public void onDestroy(){
super.onDestroy();
}
}
现在我有我的活动试图绑定到 GPSService。InSituApp.java
公共类 InSituApp 扩展 Activity{
GPSService gpsService;
boolean mBound = false;
public Button buttonGPS;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
startService(new Intent(this, GPSService.class));
//startService(new Intent(this, MyService.class));
// buttonGPS = (Button) findViewById(R.id.button1); }
@Override
protected void onStart() {
super.onStart();
System.out.println("ENTERED IN ONSTART");
// Bind to GPSService
Intent intent = new Intent(this, GPSService.class);
bindService(intent, mConnection, Context.BIND_AUTO_CREATE);
}
@Override
protected void onStop() {
super.onStop();
// Unbind from the service
if (mBound) {
unbindService(mConnection);
mBound = false;
}
}
/** Called when a button is clicked (the button in the layout file attaches to
* this method with the android:onClick attribute) */
public void onButtonClick(View v) {
System.out.println("DIDNT ENTERED IN BOUND");
if (mBound) {
// Call a method from the LocalService.
// However, if this call were something that might hang, then this request should
// occur in a separate thread to avoid slowing down the activity performance.
System.out.println("ENTERED IN BOUND");
double latitude = gpsService.getLatitude();
double longitude = gpsService.getLongitude();
double accuracy = gpsService.getAccuracy();
long timestamp = gpsService.getTimestamp();
Toast.makeText(this, "latitude: " + latitude, Toast.LENGTH_SHORT).show();
Toast.makeText(this, "longitude: " + longitude, Toast.LENGTH_SHORT).show();
Toast.makeText(this, "accuracy: " + accuracy, Toast.LENGTH_SHORT).show();
Toast.makeText(this, "timestamp: " + timestamp, Toast.LENGTH_SHORT).show();
}
}
/** Defines callbacks for service binding, passed to bindService() */
private ServiceConnection mConnection = new ServiceConnection() {
@Override
public void onServiceConnected(ComponentName className,
IBinder service) {
// We've bound to LocalService, cast the IBinder and get LocalService instance
System.out.println("ENTERED IN ONSERVICE CONNECTED");
LocalBinder binder = (LocalBinder) service;
gpsService = binder.getService();
System.out.println("GPSService: "+gpsService!=null);
mBound = true;
}
@Override
public void onServiceDisconnected(ComponentName arg0) {
mBound = false;
System.out.println("ENTERED IN ONSERVICE DISCONNECTED");
}
};
}
这段代码从不调用onServiceConnected里面的方法mConnection。这里有什么问题？onStart 中的 bindService 调用返回 false。这是为什么？
编辑：
清单.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="main.inSituApp"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="18" />
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name" >
<activity
android:label="@string/app_name"
android:name="main.inSituApp.InSituApp" >
<intent-filter >
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<service android:name=".GPSService" />
<service android:name=".FileObservingService" />
</application>
</manifest>