下面是效果：
采样点取得太频繁所以看起来像是一个个点。。。 可以自己设计算法只取有用的点。
为了方便，我直接修改百度提供的示例代码。
要修改的是BMapApiDemoApp.java,LocationOverlay.java还有自定义一个继承自Overlay的RunLineOverlay。
BMapApiDemoApp:
public class BMapApiDemoApp extendsApplication {staticBMapApiDemoApp mDemoApp;//百度MapAPI的管理类
BMapManager mBMapMan = null;//授权Key//TODO: 请输入您的Key,//申请地址：/wiki/static/imap/key/
String mStrKey = "你的Key";boolean m_bKeyRight = true; //授权Key正确，验证通过//常用事件监听，用来处理通常的网络错误，授权验证错误等
static class MyGeneralListener implementsMKGeneralListener {
@Overridepublic void onGetNetworkState(intiError) {
Log.d("MyGeneralListener", "onGetNetworkState error is "+iError);
Toast.makeText(BMapApiDemoApp.mDemoApp.getApplicationContext(),"您的网络出错啦！",
Toast.LENGTH_LONG).show();
}
@Overridepublic void onGetPermissionState(intiError) {
Log.d("MyGeneralListener", "onGetPermissionState error is "+iError);if (iError ==MKEvent.ERROR_PERMISSION_DENIED) {//授权Key错误：
Toast.makeText(BMapApiDemoApp.mDemoApp.getApplicationContext(),"请在BMapApiDemoApp.java文件输入正确的授权Key！",
Toast.LENGTH_LONG).show();
BMapApiDemoApp.mDemoApp.m_bKeyRight= false;
}
}
}
@Overridepublic voidonCreate() {
Log.v("BMapApiDemoApp", "onCreate");
mDemoApp= this;
mBMapMan= new BMapManager(this);boolean isSuccess = mBMapMan.init(this.mStrKey, newMyGeneralListener());//初始化地图sdk成功，设置定位监听时间
if(isSuccess) {
mBMapMan.getLocationManager().enableProvider(MKLocationManager.MK_GPS_PROVIDER);
mBMapMan.getLocationManager().setNotifyInternal(10, 5);
}else{//地图sdk初始化失败，不能使用sdk
}super.onCreate();
}
@Override//建议在您app的退出之前调用mapadpi的destroy()函数，避免重复初始化带来的时间消耗
public voidonTerminate() {//TODO Auto-generated method stub
if (mBMapMan != null) {
mBMapMan.destroy();
mBMapMan= null;
}super.onTerminate();
}
}
mStrKey的值是你申请来的Key，申请地址上面有。
onCreate里加了句mBMapMan.getLocationManager().enableProvider(MKLocationManager.MK_GPS_PROVIDER);用来打开GPS位置。
RunLineOverlay：
public class RunLineOverlay extendsOverlay {private ListmList;publicRunLineOverlay() {//TODO Auto-generated constructor stub
super();
mList=new ArrayList();
}
@Overridepublic void draw(Canvas arg0, MapView arg1, booleanarg2) {//TODO Auto-generated method stub
super.draw(arg0, arg1, arg2);
Projection projection=arg1.getProjection();
Paint paint=newPaint();
paint.setColor(Color.BLACK);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(5.0f);
Point p1=projection.toPixels(mList.get(0), null);
Point p2=projection.toPixels(mList.get(0), null);for(GeoPoint item : mList) {
p1.x=p2.x;
p1.y=p2.y;
p2=projection.toPixels(item, null);
arg0.drawLine(p1.x, p1.y, p2.x, p2.y, paint);
}
}public ListgetmList() {returnmList;
}public void setmList(ListmList) {this.mList =mList;
}public voidaddGeoPoint(GeoPoint point){
mList.add(point);
}
}
这是一个自定义的用于在底图上根据点画出轨迹的覆盖物。Projection用于经纬度和屏幕像素点的转换。大概功能就是取出经纬度点然后转成屏幕像素点然后连成轨迹。
LocationOverlay：
public class LocationOverlay extendsMapActivity {
MapView mMapView= null;
LocationListener mLocationListener= null;//onResume时注册此listener，onPause时需要Remove
MyLocationOverlay mLocationOverlay = null; //定位图层
RunLineOverlay mRunLine=null;protected voidonCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);
setContentView(R.layout.mapviewdemo);
BMapApiDemoApp app= (BMapApiDemoApp)this.getApplication();if (app.mBMapMan == null) {
app.mBMapMan= newBMapManager(getApplication());
app.mBMapMan.init(app.mStrKey,newBMapApiDemoApp.MyGeneralListener());
}
app.mBMapMan.start();//如果使用地图SDK，请初始化地图Activity
super.initMapActivity(app.mBMapMan);
mMapView=(MapView)findViewById(R.id.bmapView);
mMapView.setBuiltInZoomControls(true);//设置在缩放动画过程中也显示overlay,默认为不绘制
mMapView.setDrawOverlayWhenZooming(true);//添加定位图层
mLocationOverlay = new MyLocationOverlay(this, mMapView);
mMapView.getOverlays().add(mLocationOverlay);//注册定位事件
mLocationListener = newLocationListener(){
@Overridepublic voidonLocationChanged(Location location) {if (location != null){
GeoPoint pt= new GeoPoint((int)(location.getLatitude()*1e6),
(int)(location.getLongitude()*1e6));if(mRunLine==null)
{mRunLine=newRunLineOverlay();
mRunLine.addGeoPoint(pt);
mMapView.getOverlays().add(mRunLine);}elsemRunLine.addGeoPoint(pt);
mMapView.getController().animateTo(pt);
}
}
};
}
@Overrideprotected voidonPause() {
BMapApiDemoApp app= (BMapApiDemoApp)this.getApplication();
app.mBMapMan.getLocationManager().removeUpdates(mLocationListener);
mLocationOverlay.disableMyLocation();
mLocationOverlay.disableCompass();//关闭指南针
app.mBMapMan.stop();super.onPause();
}
@Overrideprotected voidonResume() {
BMapApiDemoApp app= (BMapApiDemoApp)this.getApplication();//注册定位事件，定位后将地图移动到定位点
app.mBMapMan.getLocationManager().requestLocationUpdates(mLocationListener);
mLocationOverlay.enableMyLocation();
mLocationOverlay.enableCompass();//打开指南针
app.mBMapMan.start();super.onResume();
}
@Overrideprotected booleanisRouteDisplayed() {//TODO Auto-generated method stub
return false;
}
}
主要修改的代码是
public void onLocationChanged(Location location) {
if (location != null){
GeoPoint pt = new GeoPoint((int)(location.getLatitude()*1e6),
(int)(location.getLongitude()*1e6));
if(mRunLine==null)
{mRunLine=new RunLineOverlay();
mRunLine.addGeoPoint(pt);
mMapView.getOverlays().add(mRunLine);}else
mRunLine.addGeoPoint(pt);
mMapView.getController().animateTo(pt);
}
当位置改变是这个方法会被调用。功能就是把新位置放入mRunLine。当然第一次要mMapView.getOverlays().add(mRunLine);把mRunLine放进mMapView的覆盖物列表，这样当mMapView被重绘时mRunLine的draw方法就会被调用。
改好后运行程序，列表点击Overlaytest，然后出去转一圈。
