android提供了LocationManager来取得位置,用LocationListener来监听位置的变化
先做一些初始化工作:
/** latitude and longitude of current location*/
public static String mLat = "";
public static String mLon = ""; /** time out for GPS location update */
private Timer mGpsTimer = new Timer();
/** TimerTask for time out of GPS location update */
private GpsTimeOutTask mGpsTimeOutTask = new GpsTimeOutTask();
/** GPS location update time out in milliseconds*/
private long mGpsTimeOut = 180000;//3 minutes
<span style="white-space:pre"> </span>public void initiLocationUtil (Context context, LocationObsever locationobsever){
mLocationObsever = locationobsever;
mContext = context;
mLocationManager = (LocationManager)mContext.getSystemService(Context.LOCATION_SERVICE);
mLocationListener = new MyLocationListener();
}
<span style="white-space:pre"> </span>public void RefreshGPS(boolean calledByCreate){
mLocationManager.removeUpdates(mLocationListener);
boolean providerEnable = true;
boolean showLocationServiceDisableNotice = true;
//看是否有GPS权限
if(mLocationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)){
//開始进行定位 mLocationListener为位置监听器
mLocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,
0,
0,
mLocationListener);
showLocationServiceDisableNotice = false;
//start time out timer
mGpsTimer = new Timer();
mGpsTimeOutTask = new GpsTimeOutTask();
mGpsTimer.schedule(mGpsTimeOutTask, mGpsTimeOut);
}
if(mLocationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)){
mLocationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER,
0,
0,
mLocationListener);
showLocationServiceDisableNotice = false;
providerEnable = true;
}
if(providerEnable){
if(mLocationObsever != null){
mLocationObsever.notifyChange(REFRESHGPS_COMPLETED, null);
}
}else{
if(mLocationObsever != null){
mLocationObsever.notifyChange(REFRESHGPS_NOPROVIDER, null);
}
}
if(showLocationServiceDisableNotice){
showLocationServiceDisabledDialog();
}
}
监听器:
private class MyLocationListener implements LocationListener{
private boolean mLocationReceived = false;
@Override
public void onLocationChanged(Location location) {
if(location != null && !mLocationReceived){
mLocationReceived = true;
String lon = String.valueOf(location.getLongitude());
String lat = String.valueOf(location.getLatitude());
if(mLocationObsever != null){
mLocationObsever.notifyChange(DEFAULT_LOCATION_COMPLETED, lat+","+lon);
}
}else if(location == null){
if(mLocationObsever != null){
mLocationObsever.notifyChange(GETLOCATION_FAILED, null);
}
}
}
@Override
public void onProviderDisabled(String provider) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onStatusChanged(String provider, int status,
Bundle extras) {
// TODO Auto-generated method stub
//if GPS provider is not accessible, try network provider
if(provider.equals(LocationManager.GPS_PROVIDER) && status != LocationProvider.AVAILABLE){
if(mLocationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)){
mLocationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER,
0,
0,
mLocationListener);
}else{
mLocationManager.removeUpdates(mLocationListener);
if(mLocationObsever != null){
mLocationObsever.notifyChange(STATUS_CHANGED, null);
}
}
}
}
}
这里用了一个Timer，3分钟后又一次去取一次位置:
private Handler mGpsTimerHandler = new Handler() {
public void handleMessage(Message msg) {
if (mLocationManager == null) {
return;
}
if (mLocationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)) {
System.out.println("=====use network to get location");
mLocationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER, 0, 0,
mLocationListener);
} else {
mLocationManager.removeUpdates(mLocationListener);
// mLocationObsever.notifyChange(SETADDLOCATIONBUTTONSTATE_1_SETLOCATIONDES_1,null);
if (mLocationObsever != null) {
mLocationObsever.notifyChange(GPSTIMEOUT, null);
}
}
}
};
界面退出的时候要关掉GPS
/**
* cancel operations of refreshing GPS
*/
public void cancelRefreshGPS(){
if(mLocationManager != null){
mLocationManager.removeUpdates(mLocationListener);
} if(mLocationObsever != null){
mLocationObsever.notifyChange(CANCELGPS_COMPLETED, null);
}
} public void destroy (){
if(mLocationManager != null){
mLocationManager.removeUpdates(mLocationListener);
} if(mGpsTimer != null){
mGpsTimer.cancel();
} cancelRefreshGPS(); mContext = null;
mLocationObsever = null; mLocationBuildingList = null; System.gc();
}
截图是
点击MAP的时候,假设採用google map,必须使用sdk带有google api,然后在application中增加<uses-library android:name="com.google.android.maps" />
然后xml是:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#FFFFFF"
android:gravity="center_horizontal"
android:orientation="vertical" > <include layout="@layout/title_list" /> <View
android:id="@+id/line"
android:layout_width="fill_parent"
android:layout_height="2dip"
android:layout_below="@id/title"
android:background="@drawable/rc_list_divider" /> <com.google.android.maps.MapView
android:id="@+id/mapview"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:apiKey="06nx-Rzpy8WU16_gjO8ZbtRYYY-junnxNArrxFg" /> </LinearLayout>
代码是:
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.around_map);
mTextView = (TextView)findViewById(R.id.title_text);
mTextView.setText("地图"); Intent intent = getIntent();
mLatitude = intent.getDoubleExtra("lat", 0.0);
mLongitude = intent.getDoubleExtra("lon", 0.0); mMapView = (MapView) findViewById(R.id.mapview);
mMapView.setClickable(true);
mMapView.setBuiltInZoomControls(true);
mMapView.setSatellite(true);
mapController = mMapView.getController();
// geoPoint = new GeoPoint((int)(mLatitude * 1E6), (int)(mLongitude * 1E6));
geoPoint=new GeoPoint((int)(30.659259*1000000),(int)(104.065762*1000000));
mMapView.displayZoomControls(true); // // 设置地图的初始大小。范围在1和21之间。1：最小尺寸，21：最大尺寸
mapController.setZoom(16);
//
// // 创建MyOverlay对象，用于在地图上绘制图形
MyOverlay myOverlay = new MyOverlay();
mMapView.getOverlays().add(myOverlay);
mapController.animateTo(geoPoint);
} @Override
protected boolean isRouteDisplayed() {
return false;
} class MyOverlay extends Overlay
{
@Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow, long when)
{
Paint paint = new Paint(); //屏幕上文字字体颜色
paint.setColor(Color.RED);
Point screenPoint = new Point(); mapView.getProjection().toPixels(geoPoint, screenPoint);
Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.location);
// 在地图上绘制图像
canvas.drawBitmap(bmp, screenPoint.x, screenPoint.y, paint);
// 在地图上绘制文字
// canvas.drawText("移动巴士", 10, 100, paint);
return super.draw(canvas, mapView, shadow, when);
}
}