How to directly move camera to current location in Google Maps Android API v2?

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Happy的楠姐
Happy的楠姐 2020-12-04 16:41

Without clicking any button, how to directly get the current location and move the camera to it.
Also, I found that there is a button on the right top of the map. When c

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  • 2020-12-04 16:51

    make sure you have these permissions:

    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
    

    Then make some activity and register a LocationListener

    package com.example.location;
    
    import android.content.Context;
    import android.location.Location;
    import android.location.LocationListener;
    import android.location.LocationManager;
    import android.os.Bundle;
    import android.view.View;
    import com.actionbarsherlock.app.SherlockFragmentActivity;
    import com.google.android.gms.maps.CameraUpdate;
    import com.google.android.gms.maps.CameraUpdateFactory;
    import com.google.android.gms.maps.GoogleMap;
    import com.google.android.gms.maps.SupportMapFragment;
    import com.google.android.gms.maps.model.LatLng;
    
    public class LocationActivity extends SherlockFragmentActivity implements LocationListener     {
    private GoogleMap map;
    private LocationManager locationManager;
    private static final long MIN_TIME = 400;
    private static final float MIN_DISTANCE = 1000;
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.map);
        map = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map)).getMap();
    
        locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, MIN_TIME, MIN_DISTANCE, this); //You can also use LocationManager.GPS_PROVIDER and LocationManager.PASSIVE_PROVIDER        
    }
    
    @Override
    public void onLocationChanged(Location location) {
        LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
        CameraUpdate cameraUpdate = CameraUpdateFactory.newLatLngZoom(latLng, 10);
        map.animateCamera(cameraUpdate);
        locationManager.removeUpdates(this);
    }
    
    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) { }
    
    @Override
    public void onProviderEnabled(String provider) { }
    
    @Override
    public void onProviderDisabled(String provider) { }
    }
    

    map.xml

    <?xml version="1.0" encoding="utf-8"?>
    <fragment xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/map"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    class="com.google.android.gms.maps.SupportMapFragment"/>
    
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  • 2020-12-04 17:03

    The above answer is not according to what Google Doc Referred for Location Tracking in Google api v2.

    I just followed the official tutorial and ended up with this class that is fetching the current location and centring the map on it as soon as i get that.

    you can extend this class to have LocationReciever to have periodic Location Update. I just executed this code on api level 7

    http://developer.android.com/training/location/retrieve-current.html

    Here it goes.

    import android.app.Activity;
    import android.app.Dialog;
    import android.content.Intent;
    import android.content.IntentSender;
    import android.location.Location;
    import android.os.Bundle;
    import android.support.v4.app.DialogFragment;
    import android.support.v4.app.FragmentActivity;
    import android.util.Log;
    import android.widget.Toast;
    
    import com.google.android.gms.common.ConnectionResult;
    import com.google.android.gms.common.GooglePlayServicesClient;
    import com.google.android.gms.common.GooglePlayServicesUtil;
    import com.google.android.gms.location.LocationClient;
    import com.google.android.gms.maps.CameraUpdate;
    import com.google.android.gms.maps.CameraUpdateFactory;
    import com.google.android.gms.maps.GoogleMap;
    import com.google.android.gms.maps.GoogleMap.OnMapLongClickListener;
    import com.google.android.gms.maps.SupportMapFragment;
    import com.google.android.gms.maps.model.LatLng;
    
    
    public class MainActivity extends FragmentActivity implements 
        GooglePlayServicesClient.ConnectionCallbacks, 
        GooglePlayServicesClient.OnConnectionFailedListener{
    
    private SupportMapFragment mapFragment;
    private GoogleMap map;
    private LocationClient mLocationClient;
    /*
     * Define a request code to send to Google Play services
     * This code is returned in Activity.onActivityResult
     */
    private final static int CONNECTION_FAILURE_RESOLUTION_REQUEST = 9000;
    
    // Define a DialogFragment that displays the error dialog
    public static class ErrorDialogFragment extends DialogFragment {
    
        // Global field to contain the error dialog
        private Dialog mDialog;
    
        // Default constructor. Sets the dialog field to null
        public ErrorDialogFragment() {
            super();
            mDialog = null;
        }
    
        // Set the dialog to display
        public void setDialog(Dialog dialog) {
            mDialog = dialog;
        }
    
        // Return a Dialog to the DialogFragment.
        @Override
        public Dialog onCreateDialog(Bundle savedInstanceState) {
            return mDialog;
        }
    }
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main_activity);
    
        mLocationClient = new LocationClient(this, this, this);
    
        mapFragment = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map));
        map = mapFragment.getMap();
    
        map.setMyLocationEnabled(true);
    
    }
    
    /*
     * Called when the Activity becomes visible.
     */
    @Override
    protected void onStart() {
        super.onStart();
        // Connect the client.
        if(isGooglePlayServicesAvailable()){
            mLocationClient.connect();
        }
    
    }
    
    /*
     * Called when the Activity is no longer visible.
     */
    @Override
    protected void onStop() {
        // Disconnecting the client invalidates it.
        mLocationClient.disconnect();
        super.onStop();
    }
    
    /*
     * Handle results returned to the FragmentActivity
     * by Google Play services
     */
    @Override
    protected void onActivityResult(
                    int requestCode, int resultCode, Intent data) {
        // Decide what to do based on the original request code
        switch (requestCode) {
    
            case CONNECTION_FAILURE_RESOLUTION_REQUEST:
                /*
                 * If the result code is Activity.RESULT_OK, try
                 * to connect again
                 */
                switch (resultCode) {
                    case Activity.RESULT_OK:
                        mLocationClient.connect();
                        break;
                }
    
        }
    }
    
    private boolean isGooglePlayServicesAvailable() {
        // Check that Google Play services is available
        int resultCode =  GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
        // If Google Play services is available
        if (ConnectionResult.SUCCESS == resultCode) {
            // In debug mode, log the status
            Log.d("Location Updates", "Google Play services is available.");
            return true;
        } else {
            // Get the error dialog from Google Play services
            Dialog errorDialog = GooglePlayServicesUtil.getErrorDialog( resultCode,
                                                                                                                  this,
                                                                                                                  CONNECTION_FAILURE_RESOLUTION_REQUEST);
    
            // If Google Play services can provide an error dialog
            if (errorDialog != null) {
                // Create a new DialogFragment for the error dialog
                ErrorDialogFragment errorFragment = new ErrorDialogFragment();
                errorFragment.setDialog(errorDialog);
                errorFragment.show(getSupportFragmentManager(), "Location Updates");
            }
    
            return false;
        }
    }
    
    /*
     * Called by Location Services when the request to connect the
     * client finishes successfully. At this point, you can
     * request the current location or start periodic updates
     */
    @Override
    public void onConnected(Bundle dataBundle) {
        // Display the connection status
        Toast.makeText(this, "Connected", Toast.LENGTH_SHORT).show();
        Location location = mLocationClient.getLastLocation();
        LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
        CameraUpdate cameraUpdate = CameraUpdateFactory.newLatLngZoom(latLng, 17);
        map.animateCamera(cameraUpdate);
    }
    
    /*
     * Called by Location Services if the connection to the
     * location client drops because of an error.
     */
    @Override
    public void onDisconnected() {
        // Display the connection status
        Toast.makeText(this, "Disconnected. Please re-connect.",
                Toast.LENGTH_SHORT).show();
    }
    
    /*
     * Called by Location Services if the attempt to
     * Location Services fails.
     */
    @Override
    public void onConnectionFailed(ConnectionResult connectionResult) {
        /*
         * Google Play services can resolve some errors it detects.
         * If the error has a resolution, try sending an Intent to
         * start a Google Play services activity that can resolve
         * error.
         */
        if (connectionResult.hasResolution()) {
            try {
                // Start an Activity that tries to resolve the error
                connectionResult.startResolutionForResult(
                        this,
                        CONNECTION_FAILURE_RESOLUTION_REQUEST);
                /*
                * Thrown if Google Play services canceled the original
                * PendingIntent
                */
            } catch (IntentSender.SendIntentException e) {
                // Log the error
                e.printStackTrace();
            }
        } else {
           Toast.makeText(getApplicationContext(), "Sorry. Location services not available to you", Toast.LENGTH_LONG).show();
        }
    }
    
    }
    
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  • 2020-12-04 17:14

    I am explaining, How to get current location and Directly move to the camera to current location with assuming that you have implemented map-v2. For more details, You can refer official doc.

    Add location service in gradle

    implementation "com.google.android.gms:play-services-location:11.0.1"
    

    Add location permission in manifest file

    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    

    Make sure you ask for RunTimePermission. I am using Ask-Permission for that. Its easy to use.

    Now refer below code to get the current location and display it on a map.

    private FusedLocationProviderClient mFusedLocationProviderClient;
    
    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            mFusedLocationProviderClient = LocationServices
                    .getFusedLocationProviderClient(getActivity());
    
    }
    
    private void getDeviceLocation() {
            try {
                if (mLocationPermissionGranted) {
                    Task<Location> locationResult = mFusedLocationProviderClient.getLastLocation();
                    locationResult.addOnCompleteListener(new OnCompleteListener<Location>() {
                        @Override
                        public void onComplete(@NonNull Task<Location> task) {
                            if (task.isSuccessful()) {
                                // Set the map's camera position to the current location of the device.
                                Location location = task.getResult();
                                LatLng currentLatLng = new LatLng(location.getLatitude(),
                                        location.getLongitude());
                                CameraUpdate update = CameraUpdateFactory.newLatLngZoom(currentLatLng,
                                        DEFAULT_ZOOM);
                                googleMap.moveCamera(update);
                            }
                        }
                    });
                }
            } catch (SecurityException e) {
                Log.e("Exception: %s", e.getMessage());
            }
    }
    

    When user granted location permission call above getDeviceLocation() method

    private void updateLocationUI() {
            if (googleMap == null) {
                return;
            }
            try {
                if (mLocationPermissionGranted) {
                    googleMap.setMyLocationEnabled(true);
                    googleMap.getUiSettings().setMyLocationButtonEnabled(true);
                    getDeviceLocation();
                } else {
                    googleMap.setMyLocationEnabled(false);
                    googleMap.getUiSettings().setMyLocationButtonEnabled(false);
                }
            } catch (SecurityException e) {
                Log.e("Exception: %s", e.getMessage());
            }
        }
    
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  • 2020-12-04 17:17

    Just change moveCamera to animateCamera like below

    Googlemap.animateCamera(CameraUpdateFactory.newLatLngZoom(locate, 16F))
    
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