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(android 地图实战开发)3 在地图上显示当前位置和自定义银行位置

news 来源：原创 2024/4/25 19:39:55

前言:

下面讲述在MapView中显示当前位置,并同时已知的银行ATM机的位置

效果图:

1 实现效果说明:

实现显示当前位置和银行ATM机的位置,主要分以下两个步骤,

1) 根据位置服务找到当前的GPS坐标

2) 将当前坐标和ATM坐标,用图层的方式显示到地图上

2 根据位置服务找到当前的GPS坐标

l 设置应用的权限

在AndroidManifest.xml文件中设置ACCESS_FINE_LOCATION权限

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

获取定位服务

String context=Context.LOCATION_SERVICE;

locationManager=(LocationManager)getSystemService(context);

根据定位服务获取位置

定位服务接口

[1] LocationManager.getLastKnownLocation(provider)

注:获取最后一次定位坐标信息

[2] void android.location.LocationManager.requestLocationUpdates(String provider, long minTime, float minDistance, LocationListener listener)

注:对指定provider进行侦听,条件为最小时间minTime ,最小距离minDistance

3 根据位置服务找到当前的GPS坐标

添加MyLocationOverlay层,显示当前位置.

List<Overlay> overlays=map_view.getOverlays(); // set location Overlay

MyLocationOverlay mylocationOver=new MyLocationOverlay(this,map_view);

overlays.add(mylocationOver);

mylocationOver.enableCompass(); //显示指南针

mylocationOver.enableMyLocation(); //允许当前位置

自定义层，显示ATM位置

集成ItemizedOverlay<OverlayItem>类

调用方式：

atm=new ATMDynamicItemizedOverlay(this.getResources().getDrawable(R.drawable.map_atm));

overlays.add(atm);

atm.addNewItem(new GeoPoint(lat.intValue()+1000,lng.intValue()), "marketText", "snippet");

4 源代码：

自定义 ATMDynamicItemizedOverlay 类

View Code

publicclass ATMDynamicItemizedOverlay extends ItemizedOverlay<OverlayItem>{

private ArrayList<OverlayItem> items ;

public ATMDynamicItemizedOverlay(Drawable defaultMarker)
    {
super(boundCenterBottom(defaultMarker));
        items=new ArrayList<OverlayItem>();
        populate();
    }

publicvoid addNewItem(GeoPoint location,String marketText,String snippet)
    {
        items.add(new OverlayItem(location,marketText,snippet));
        populate();
    }

publicvoid removeItem(int index)
    {
        items.remove(index);
        populate();

    }

    @Override
protected OverlayItem createItem(int index) {
// TODO Auto-generated method stub
        
return items.get(index);
    }

    @Override
publicint size() {
// TODO Auto-generated method stub
return items.size();
    }

}

窗体文件

View Code

publicclass LocationMap extends MapActivity {
    LocationManager locationManager;
    MapView map_view;
    ATMDynamicItemizedOverlay atm;
     @Override   
publicvoid onCreate(Bundle savedInstanceState) {  
super.onCreate(savedInstanceState);  
         setContentView(R.layout.locationmap);

//add bank button onclick event
         ImageView imgView_back=(ImageView)findViewById(R.id.map_imgView_back);
         imgView_back.setOnClickListener(new  ImageView.OnClickListener()
        {
publicvoid onClick(View v){
                ViewUtility.NavigateActivate(LocationMap.this,Main.class );    

            }
        });

//set MapControl 
        map_view =(MapView)findViewById(R.id.map_view);
        map_view.setStreetView(true);
        map_view.setTraffic(true);
        map_view.setBuiltInZoomControls(false);
        map_view.setSatellite(false);  

        List<Overlay> overlays=map_view.getOverlays(); // set location Overlay
        MyLocationOverlay mylocationOver=new MyLocationOverlay(this,map_view);
        overlays.add(mylocationOver);
        mylocationOver.enableCompass();
        mylocationOver.enableMyLocation();

//set atm Overlay
        atm=new ATMDynamicItemizedOverlay(this.getResources().getDrawable(R.drawable.map_atm));
        overlays.add(atm);
        String context=Context.LOCATION_SERVICE;
        locationManager=(LocationManager)getSystemService(context);
        String provider=LocationManager.GPS_PROVIDER;


//OverlayItem a=new OverlayItem(null, provider, provider;
        Location location =locationManager.getLastKnownLocation(provider);
if(location!=null)
        {
            UpdateMapView(location);
        }

        locationManager.requestLocationUpdates(provider, 10000, 5, locationListener );

     }

/* By new location ,update MapWiew's Label */
privatevoid UpdateMapView(Location location)
     {
           MapController mapcontroller=map_view.getController();

            Double lat=location.getLatitude()*1E6;
            Double lng=location.getLongitude()*1E6;
            GeoPoint point=new GeoPoint(lat.intValue(),lng.intValue());

            mapcontroller.setCenter(point);
            mapcontroller.setZoom(20);
            mapcontroller.animateTo(point);

            atm.addNewItem(new GeoPoint(lat.intValue()+1000,lng.intValue()), "marketText", "snippet");
            Toast.makeText(this, "lat:"+ String.valueOf(lat.intValue())+"lng:"+String.valueOf(lng.intValue()), Toast.LENGTH_SHORT).show();
     }

     @Override
publicboolean onKeyDown(int keyCode, KeyEvent event) {
if(keyCode == KeyEvent.KEYCODE_BACK){
                ViewUtility.NavigateActivate(LocationMap.this, Main.class);
            }
returnfalse;
        }
    @Override
protectedboolean isRouteDisplayed() {
// TODO Auto-generated method stub
returnfalse;
    }

//create location listener
private LocationListener locationListener =new LocationListener(){
//location is changed
            @Override
publicvoid onLocationChanged(Location location) {
                UpdateMapView(location);
                 Log.d("Location", "onLocationChanged");
             }

//location is Disable
       @Override
publicvoid onProviderDisabled(String provider) {
               Log.d("Location", "onProviderDisabled");
             }

//location is enabled
             @Override
publicvoid onProviderEnabled(String provider) {
            Log.d("Location", "onProviderEnabled");
             }

//location's status changes
             @Override
publicvoid onStatusChanged(String provider, int status, Bundle extras) {
                Log.d("Location", "onStatusChanged");
             }
     };

}