我不确定出了什么问题，但我试图让我的谷歌地图片段在开始时放大到特定位置。由于某种原因，它无法正常工作，并且默认情况下仍会放大到非洲。这是我的代码。
public class OutbreakMap extends Activity implements LocationListener {
double lat=50;
double longi=50;
private LocationManager locationManager;
private String provider;
private MapFragment mMapFragment;
private GoogleMap googleMap;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.location);
// Get the location manager
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
LocationManager service = (LocationManager) getSystemService(LOCATION_SERVICE);
boolean enabled = service.isProviderEnabled(LocationManager.GPS_PROVIDER);
// Check if enabled and if not send user to the GSP settings
// Better solution would be to display a dialog and suggesting to
// go to the settings
if (!enabled) {
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this);
// set title
alertDialogBuilder.setTitle("Turn On Your GPS");
// set dialog message
alertDialogBuilder
.setMessage("Please turn on your GPS to track sickness in your area!")
.setCancelable(false)
.setPositiveButton("Yes",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int id) {
// if this button is clicked, close
// current activity
OutbreakMap.this.finish();
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(intent);
}
})
.setNegativeButton("No",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int id) {
// if this button is clicked, just close
// the dialog box and do nothing
dialog.cancel();
}
});
// create alert dialog
AlertDialog alertDialog = alertDialogBuilder.create();
// show it
alertDialog.show();
}
// Define the criteria how to select the locatioin provider -> use
// default
Criteria criteria = new Criteria();
provider = locationManager.getBestProvider(criteria, false);
Location location = locationManager.getLastKnownLocation(provider);
// Initialize the location fields
if (location != null) {
System.out.println("Provider " + provider + " has been selected.");
onLocationChanged(location);
} else {
Toast.makeText(getApplicationContext(),"Location not found",Toast.LENGTH_SHORT);
}
mMapFragment = MapFragment.newInstance();
FragmentTransaction fragmentTransaction =
getFragmentManager().beginTransaction();
fragmentTransaction.add(R.id.map, mMapFragment);
fragmentTransaction.commit();
googleMap = ((MapFragment) getFragmentManager().findFragmentById(R.id.map))
.getMap();
setUpMapIfNeeded();
googleMap.setMapType(GoogleMap.MAP_TYPE_SATELLITE);
if(location != null) {
lat=location.getLatitude();
longi=location.getLongitude();
}
CameraPosition cameraPosition = new CameraPosition.Builder()
.target(new LatLng(lat,longi)) // Sets the center of the map to Mountain View
.zoom(17) // Sets the zoom
// Sets the tilt of the camera to 30 degrees
.build(); // Creates a CameraPosition from the builder
googleMap.animateCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));
UiSettings uiSettings=googleMap.getUiSettings();
uiSettings.setAllGesturesEnabled(false);
// Initialize the location fields
if (location != null) {
System.out.println("Provider " + provider + " has been selected.");
onLocationChanged(location);
} else {
Toast.makeText(getApplicationContext(),"Couldn't Find Location",Toast.LENGTH_SHORT);
}
ParseGeoPoint userLoc= new ParseGeoPoint(lat,longi);
ParseQuery query= new ParseQuery("Outbreak");
query.whereWithinMiles("location",userLoc,1);
query.findInBackground(new FindCallback() {
public void done(List<ParseObject> objects, ParseException e) {
if (e == null) {
GetOutbreaks.getOutBreaksNearMe(googleMap,lat,longi,objects);
Toast.makeText(getApplicationContext(),"Recieved Outbreak Data",Toast.LENGTH_SHORT);
} else {
e.printStackTrace();
Toast.makeText(getApplicationContext(),"Could Not Download Data",Toast.LENGTH_SHORT);
}
}
});
// moveToPrescription();
// moveToPrescription();
}
/* Request updates at startup */
@Override
protected void onResume() {
super.onResume();
locationManager.requestLocationUpdates(provider, 400, 1, this);
}
/* Remove the locationlistener updates when Activity is paused */
@Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}
@Override
public void onLocationChanged(Location location) {
int lat = (int) (location.getLatitude());
int lng = (int) (location.getLongitude());
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
@Override
public void onProviderEnabled(String provider) {
Toast.makeText(this, "Enabled new provider " + provider,
Toast.LENGTH_SHORT).show();
}
@Override
public void onProviderDisabled(String provider) {
Toast.makeText(this, "Disabled provider " + provider,
Toast.LENGTH_SHORT).show();
}
public void moveToPrescription(){
Intent intent = new Intent(this,Prescription.class);
startActivity(intent);
}
private void setUpMapIfNeeded() {
// Do a null check to confirm that we have not already instantiated the map.
if (googleMap == null) {
googleMap = ((MapFragment) getFragmentManager().findFragmentById(R.id.map))
.getMap();
// Check if we were successful in obtaining the map.
if (googleMap != null) {
// The Map is verified. It is now safe to manipulate the map.
}
}
}
}
另外，这是我的地图片段活动的 xml 布局
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/map"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:name="com.google.android.gms.maps.MapFragment"/>
</LinearLayout>
还有我的 Android 清单
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.parse.starter"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="4" android:targetSdkVersion="15"/>
<permission
android:name="com.example.mapdemo.permission.MAPS_RECEIVE"
android:protectionLevel="signature"/>
<uses-permission android:name="com.example.mapdemo.permission.MAPS_RECEIVE"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES"/>
<!-- The following two permissions are not required to use
Google Maps Android API v2, but are recommended. -->
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.WAKE_LOCK"/>
<application
android:name="ParseApplication"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name" >
<activity
android:name=".ParseStarterProjectActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".Register"/>
<activity android:name=".Login"/>
<activity android:name=".Home"/>
<activity android:name=".OutbreakMap"/>
<activity android:name=".Prescription"/>
<activity android:name=".MyPrescriptions"/>
<receiver android:name=".AlarmManagerBroadcastReceiver"></receiver>
<uses-library android:name="com.google.android.maps"/>
<meta-data
android:name="com.google.android.maps.v2.API_KEY"
android:value="My Maps API Key is Here"/>
</application>
<uses-feature android:glEsVersion="0x00020000" android:required="true" />
</manifest>
LogCat 没有显示任何错误。谢谢您的帮助！