LocationManager.java revision c343fa06491ee5677b735920032d92e055c16366 
1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.camera;
18
19import android.content.Context;
20import android.location.Location;
21import android.location.LocationProvider;
22import android.os.Bundle;
23import android.util.Log;
24
25/**
26 * A class that handles everything about location.
27 */
28public class LocationManager {
29    private static final String TAG = "LocationManager";
30
31    private Context mContext;
32    private Listener mListener;
33    private android.location.LocationManager mLocationManager;
34    private boolean mRecordLocation;
35
36    LocationListener [] mLocationListeners = new LocationListener[] {
37            new LocationListener(android.location.LocationManager.GPS_PROVIDER),
38            new LocationListener(android.location.LocationManager.NETWORK_PROVIDER)
39    };
40
41    public interface Listener {
42        public void showGpsOnScreenIndicator(boolean hasSignal);
43        public void hideGpsOnScreenIndicator();
44   }
45
46    public LocationManager(Context context, Listener listener) {
47        mContext = context;
48        mListener = listener;
49    }
50
51    public void startReceivingLocationUpdates() {
52        mRecordLocation = true;
53        if (mLocationManager == null) {
54            mLocationManager = (android.location.LocationManager)
55                    mContext.getSystemService(Context.LOCATION_SERVICE);
56        }
57        if (mLocationManager != null) {
58            try {
59                mLocationManager.requestLocationUpdates(
60                        android.location.LocationManager.NETWORK_PROVIDER,
61                        1000,
62                        0F,
63                        mLocationListeners[1]);
64            } catch (SecurityException ex) {
65                Log.i(TAG, "fail to request location update, ignore", ex);
66            } catch (IllegalArgumentException ex) {
67                Log.d(TAG, "provider does not exist " + ex.getMessage());
68            }
69            try {
70                mLocationManager.requestLocationUpdates(
71                        android.location.LocationManager.GPS_PROVIDER,
72                        1000,
73                        0F,
74                        mLocationListeners[0]);
75                mListener.showGpsOnScreenIndicator(false);
76            } catch (SecurityException ex) {
77                Log.i(TAG, "fail to request location update, ignore", ex);
78            } catch (IllegalArgumentException ex) {
79                Log.d(TAG, "provider does not exist " + ex.getMessage());
80            }
81            Log.d(TAG, "startReceivingLocationUpdates");
82        }
83    }
84
85    public void stopReceivingLocationUpdates() {
86        mRecordLocation = false;
87        if (mLocationManager != null) {
88            for (int i = 0; i < mLocationListeners.length; i++) {
89                try {
90                    mLocationManager.removeUpdates(mLocationListeners[i]);
91                } catch (Exception ex) {
92                    Log.i(TAG, "fail to remove location listners, ignore", ex);
93                }
94            }
95            Log.d(TAG, "stopReceivingLocationUpdates");
96        }
97        mListener.hideGpsOnScreenIndicator();
98    }
99
100    public Location getCurrentLocation() {
101        // go in best to worst order
102        for (int i = 0; i < mLocationListeners.length; i++) {
103            Location l = mLocationListeners[i].current();
104            if (l != null) return l;
105        }
106        Log.d(TAG, "No location received yet.");
107        return null;
108    }
109
110    private class LocationListener
111            implements android.location.LocationListener {
112        Location mLastLocation;
113        boolean mValid = false;
114        String mProvider;
115
116        public LocationListener(String provider) {
117            mProvider = provider;
118            mLastLocation = new Location(mProvider);
119        }
120
121        @Override
122        public void onLocationChanged(Location newLocation) {
123            if (newLocation.getLatitude() == 0.0
124                    && newLocation.getLongitude() == 0.0) {
125                // Hack to filter out 0.0,0.0 locations
126                return;
127            }
128            // If GPS is available before start camera, we won't get status
129            // update so update GPS indicator when we receive data.
130            if (mRecordLocation &&
131                    android.location.LocationManager.GPS_PROVIDER.equals(mProvider)) {
132                mListener.showGpsOnScreenIndicator(true);
133            }
134            if (!mValid) {
135                Log.d(TAG, "Got first location.");
136            }
137            mLastLocation.set(newLocation);
138            mValid = true;
139        }
140
141        @Override
142        public void onProviderEnabled(String provider) {
143        }
144
145        @Override
146        public void onProviderDisabled(String provider) {
147            mValid = false;
148        }
149
150        @Override
151        public void onStatusChanged(
152                String provider, int status, Bundle extras) {
153            switch(status) {
154                case LocationProvider.OUT_OF_SERVICE:
155                case LocationProvider.TEMPORARILY_UNAVAILABLE: {
156                    mValid = false;
157                    if (mRecordLocation &&
158                            android.location.LocationManager.GPS_PROVIDER.equals(provider)) {
159                        mListener.showGpsOnScreenIndicator(false);
160                    }
161                    break;
162                }
163            }
164        }
165
166        public Location current() {
167            return mValid ? mLastLocation : null;
168        }
169    }
170}
171