How do I zoom in automatically to the current loca

I have integrated the Google Maps API in Android Studio, and it also finds the current location, but I want to increase the zoom level, so that I can view my current location more clearly and precised. How do I increase the zoom level?

You can find my code below:

package com.example.umar.testgoogle;

import android.location.Location;

import android.content.IntentSender;
import android.location.Location;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.util.Log;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;
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;
import com.google.android.gms.maps.model.MarkerOptions;

public class MapsActivity extends FragmentActivity implements
    GoogleApiClient.ConnectionCallbacks,
    GoogleApiClient.OnConnectionFailedListener,
    LocationListener {

    public static final String TAG = MapsActivity.class.getSimpleName();

    /*
     * 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;

    private GoogleMap mMap; // Might be null if Google Play services APK is
                            // not available.

    private GoogleApiClient mGoogleApiClient;
    private LocationRequest mLocationRequest;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_maps);
        setUpMapIfNeeded();

        mGoogleApiClient = new GoogleApiClient.Builder(this)
            .addConnectionCallbacks(this)
            .addOnConnectionFailedListener(this)
            .addApi(LocationServices.API)
            .build();

        // Create the LocationRequest object
        mLocationRequest = LocationRequest.create()
            .setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
            .setInterval(10 * 1000)        // 10 seconds, in milliseconds
            .setFastestInterval(1 * 1000); // 1 second, in milliseconds
    }

    @Override
    protected void onResume() {
        super.onResume();
        setUpMapIfNeeded();
        mGoogleApiClient.connect();
    }

    @Override
    protected void onPause() {
        super.onPause();

        if (mGoogleApiClient.isConnected()) {
                    LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
            mGoogleApiClient.disconnect();
        }
    }

    /**
     * Sets up the map if it is possible to do so (i.e., the Google Play
     * services APK is correctly installed) and the map has not already
     * been instantiated.. This will ensure that we only ever call
     * {@link #setUpMap()} once when {@link #mMap} is not null.
     * <p/>
     * If it isn't installed {@link SupportMapFragment} (and
     * {@link com.google.android.gms.maps.MapView MapView}) will show a
     * prompt for the user to install/update the Google Play services
     * APK on their device.
     * <p/>
     * A user can return to this FragmentActivity after following the
     * prompt and correctly installing/updating/enabling the Google
     * Play services. Since the FragmentActivity may not have been
     * completely destroyed during this process (it is likely that it
     * would only be stopped or paused), {@link #onCreate(Bundle)} may
     * not be called again so we should call this method in
     * {@link #onResume()} to guarantee that it will be called.
     */
    private void setUpMapIfNeeded() {
        // Do a null check to confirm that we have not already instantiated the map.
        if (mMap == null) {
            // Try to obtain the map from the SupportMapFragment.
            mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map))
                    .getMap();
            // Check if we were successful in obtaining the map.
            if (mMap != null) {
                setUpMap();
            }
        }
    }

    /**
     * This is where we can add markers or lines, add listeners or move
     * the camera. In this case, we just add a marker near Africa.
     * <p/>
     * This should only be called once and when we are sure
     *  that {@link #mMap} is not null.
     */
    private void setUpMap() {
        mMap.addMarker(new MarkerOptions().position(new LatLng(0, 0)).title("Marker"));
    }

    private void handleNewLocation(Location location) {
        Log.d(TAG, location.toString());

        double currentLatitude = location.getLatitude();
        double currentLongitude = location.getLongitude();

        LatLng latLng = new LatLng(currentLatitude, currentLongitude);

        //mMap.addMarker(new MarkerOptions().position(new LatLng(currentLatitude, currentLongitude)).title("Current Location"));
        MarkerOptions options = new MarkerOptions()
                .position(latLng)
                .title("I am here!");
        mMap.addMarker(options);
        mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
    }

    @Override
    public void onConnected(Bundle bundle) {
        Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);

        if (location == null) {
            LocationServices.FusedLocationApi.requestLocationUpdates(
                mGoogleApiClient, mLocationRequest, this);
        }
        else {
            handleNewLocation(location);
        }
    }

    @Override
    public void onConnectionSuspended(int i) {

    }

    @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 {
            /*
             * If no resolution is available, display a dialog to the
             * user with the error.
             */
            Log.i(TAG, "Location services connection failed with code " +
                       connectionResult.getErrorCode());
        }
    }

    @Override
    public void onLocationChanged(Location location) {
        handleNewLocation(location);
    }
}

回答1:

Change from:

mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));

to:

float zoomLevel = 16.0f; //This goes up to 21
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng, zoomLevel));

public static CameraUpdate newLatLngZoom (LatLng latLng, float zoom)

Returns a CameraUpdate that moves the center of the screen to a latitude and longitude specified by a LatLng object, and moves to the given zoom level.

Parameters latLng a LatLng object containing the desired latitude and longitude. zoom the desired zoom level, in the range of 2.0 to 21.0. Values below this range are set to 2.0, and values above it are set to 21.0. Increase the value to zoom in. Not all areas have tiles at the largest zoom levels. Returns a CameraUpdate containing the transformation.

回答2:

or you can also use animateCamerma method to get an animated zooming effect.

//  This is method returns the lastKnownlocation and store it in location object from where then you can retrive latitute and longitude.
Location location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER); 
mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(location.getLatitude(), location.getLongitude()), 20.0f));