LocationSourceDemoActivity.java

/*
 * Copyright (C) 2012 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.example.mapdemo;

import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.GoogleMap.OnMapLongClickListener;
import com.google.android.gms.maps.LocationSource;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;

import android.location.Location;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;

/**
 * This shows how to use a custom location source.
 */
public class LocationSourceDemoActivity extends FragmentActivity {
    /**
     * A {@link LocationSource} which reports a new location whenever a user long presses the map at
     * the point at which a user long pressed the map.
     */
    private static class LongPressLocationSource implements LocationSource, OnMapLongClickListener {
        private OnLocationChangedListener mListener;

        /**
         * Flag to keep track of the activity's lifecycle. This is not strictly necessary in this
         * case because onMapLongPress events don't occur while the activity containing the map is
         * paused but is included to demonstrate best practices (e.g., if a background service were
         * to be used).
         */
        private boolean mPaused;

        @Override
        public void activate(OnLocationChangedListener listener) {
            mListener = listener;
        }

        @Override
        public void deactivate() {
            mListener = null;
        }

        @Override
        public void onMapLongClick(LatLng point) {
            if (mListener != null && !mPaused) {
                Location location = new Location("LongPressLocationProvider");
                location.setLatitude(point.latitude);
                location.setLongitude(point.longitude);
                location.setAccuracy(100);
                mListener.onLocationChanged(location);
            }
        }

        public void onPause() {
            mPaused = true;
        }

        public void onResume() {
            mPaused = false;
        }

    }

    private LongPressLocationSource mLocationSource;

    private GoogleMap mMap;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.basic_demo);

        mLocationSource = new LongPressLocationSource();

        setUpMapIfNeeded();
    }

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

        mLocationSource.onResume();
    }

    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();
            }
        }
    }

    private void setUpMap() {
        mMap.setLocationSource(mLocationSource);
        mMap.setOnMapLongClickListener(mLocationSource);
        mMap.setMyLocationEnabled(true);
    }

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