首届 Google 暑期大学生博客分享大赛——2010 Android 篇 android关于 Google Map 开发的应用

                     首届 Google 暑期大学生博客分享大赛——2010 Android 篇

                                             android关于 Google Map 开发的应用

   

   今年年初宿舍的哥们购买了HTC 基于android系统的手机，第一次接触了试玩了android的真机，感觉非常棒。其实在09年的时候就开始关注Google 的android的手机操作系统，在当时就和同学讨论认为Google开发的android手机系统，认为是一个非常好的有前途的系统，今年年初由于同学的手机坏了，他买了HTC 的G2，我时常把他的手机借过来来玩玩。后来我感觉我自己也可以自己学习android手机的应用软件的开发，学习android的开发，让自己多学点东西，从5月份自己开始慢慢的学习android的开发的知识，自己有买了两本书由于学习android的开发。

     最近从网上看到了“首届 Google 暑期大学生博客分享大赛——2010 Android 篇”正好用所学的android的知识开发结合Google Map编写一个android的程序。

     该程序是用的android 1.6版本开发的，实现的功能是计算你在某点走到另一点的距离，所用的时间，你走过的路程用线在地图上给画出以及你所在位置的经纬度在地图上标注出。还可以按MENU出现地图模式和退出两个选项，地图模式提高了三种模式分别为街景模式，交通流量，卫星模式，退出将直接退出程序。

   

   程序运行时如果没有开启GPS的功能将会出现如果

      

     

MENU是出现情况如图

地图模式选择

   

 

显示距离时间经纬度情况图

 

下面贴出部分代码MapDistance.java类

public class MapDistance extends MapActivity { /** Called when the activity is first created. */ private TextView mTextView,mTextView01,mTextView02; private Button mButton01; private Button mButton02; private Button mButton03; private Button mButton04; private MapView mMapView; private MapController mMapController; private LocationManager mLocationManager; private Location mLocation; private String mLocationPrivider=""; private int zoomLevel=0; private GeoPoint gp1; private GeoPoint gp2; private boolean _run=false; private double distance=0; private static final int ViewMode = Menu.FIRST ; private static final int Exit = Menu.FIRST +1; public static String latLongString; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); mMapView=(MapView)findViewById(R.id.myMapView1); mMapController=mMapView.getController(); mTextView = (TextView)findViewById(R.id.myText1); mTextView01 = (TextView)findViewById(R.id.myText2); mTextView02 = (TextView)findViewById(R.id.myText3); mButton01 = (Button)findViewById(R.id.myButton1); mButton02 = (Button)findViewById(R.id.myButton2); mButton03 = (Button)findViewById(R.id.myButton3); mButton04 = (Button)findViewById(R.id.myButton4); zoomLevel=17; mMapController.setZoom(zoomLevel); mLocationManager=(LocationManager)getSystemService(Context.LOCATION_SERVICE); getLocationPrivider(); if(mLocation!=null){ gp1=getGeoByLocation(mLocation); gp2=gp1; /*将MapView的中点移到目前位置*/ refreshMapView(); /*设定事件的Listen*/ mLocationManager.requestLocationUpdates(mLocationPrivider,2000, 10, mLocationListener); } else{ new AlertDialog.Builder(MapDistance.this).setTitle("系统消息") .setMessage(getResources().getString(R.string.str_message)) .setNegativeButton("确定",new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int which) { MapDistance.this.finish(); } }) .show(); } mButton01.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { gp1=gp2; /*清除Overlay*/ resetOverlay(); //画起点 setStartPoint(); refreshMapView(); distance=0; mTextView.setText("移动的距离为：0M"); _run=true; SimpleDateFormat bartDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); Date nowdate = new Date(); mTextView01.setText("开始的时间是："+bartDateFormat.format(nowdate)); mTextView02.setText("结束的时间是："); MyLocationOverlay myLocationOverlay=new MyLocationOverlay(); List<Overlay>list=mMapView.getOverlays(); list.add(myLocationOverlay); } }); mButton02.setOnClickListener(new Button.OnClickListener(){ public void onClick(View v) { //画终点 setEndPoint(); /* 更新MapView */ refreshMapView(); _run=false; SimpleDateFormat bartDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); Date nowdate1 = new Date(); mTextView02.setText("结束的时间是："+bartDateFormat.format(nowdate1)); MyLocationOverlay myLocationOverlay=new MyLocationOverlay(); List<Overlay>list=mMapView.getOverlays(); list.add(myLocationOverlay); } }); /* 缩小Button */ mButton03.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { zoomLevel--; if(zoomLevel<1) { zoomLevel = 1; } mMapController.setZoom(zoomLevel); } }); /* 放大Button */ mButton04.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { zoomLevel++; if(zoomLevel>mMapView.getMaxZoomLevel()) { zoomLevel = mMapView.getMaxZoomLevel(); } mMapController.setZoom(zoomLevel); } }); } public final LocationListener mLocationListener=new LocationListener() { public void onLocationChanged(Location location){ if(_run){ gp2=getGeoByLocation(location); setRoute(); refreshMapView(); distance+=GetDistance(gp1,gp2); mTextView.setText("移动的距离为："+format(distance)+"M"); gp1=gp2; } } public void onProviderDisabled(String provider) { } public void onProviderEnabled(String provider) { } public void onStatusChanged(String provider,int status, Bundle extras) { } }; /*获取GeoPiont的方法*/ private GeoPoint getGeoByLocation(Location location) { GeoPoint gp = null; try { if (location != null) { double geoLatitude = location.getLatitude()*1E6; double geoLongitude = location.getLongitude()*1E6; gp = new GeoPoint((int) geoLatitude, (int) geoLongitude); double lat=location.getLatitude(); double lng=location.getLongitude(); latLongString=lat+","+lng; } } catch(Exception e) { e.printStackTrace(); } return gp; } /* 取得LocationProvider */ public void getLocationPrivider() { Criteria mCriteria01 = new Criteria(); mCriteria01.setAccuracy(Criteria.ACCURACY_FINE); mCriteria01.setAltitudeRequired(false); mCriteria01.setBearingRequired(false); mCriteria01.setCostAllowed(true); mCriteria01.setPowerRequirement(Criteria.POWER_LOW); mLocationPrivider = mLocationManager .getBestProvider(mCriteria01, true); mLocation = mLocationManager .getLastKnownLocation(mLocationPrivider); } private void setStartPoint() { int mode=1; MyOverLay mOverlay = new MyOverLay(gp1,gp2,mode); List<Overlay> overlays = mMapView.getOverlays(); overlays.add(mOverlay); } private void setRoute() { int mode=2; MyOverLay mOverlay = new MyOverLay(gp1,gp2,mode); List<Overlay> overlays = mMapView.getOverlays(); overlays.add(mOverlay); // insertData(); } private void setEndPoint() { int mode=3; MyOverLay mOverlay = new MyOverLay(gp1,gp2,mode); List<Overlay> overlays = mMapView.getOverlays(); overlays.add(mOverlay); } /* 重设Overlay的method */ private void resetOverlay() { List<Overlay> overlays = mMapView.getOverlays(); overlays.clear(); } /* 更新MapView的method */ public void refreshMapView() { mMapView.displayZoomControls(true); MapController myMC = mMapView.getController(); myMC.animateTo(gp2); myMC.setZoom(zoomLevel); mMapView.setSatellite(false); } /* 取得两点间距离的method */ public double GetDistance(GeoPoint gp1,GeoPoint gp2) { double Lat1r = ConvertDegreeToRadians(gp1.getLatitudeE6()/1E6); double Lat2r = ConvertDegreeToRadians(gp2.getLatitudeE6()/1E6); double Long1r= ConvertDegreeToRadians(gp1.getLongitudeE6()/1E6); double Long2r= ConvertDegreeToRadians(gp2.getLongitudeE6()/1E6); /* 地球的半径*/ double R = 6371; double d = Math.acos(Math.sin(Lat1r)*Math.sin(Lat2r)+ Math.cos(Lat1r)*Math.cos(Lat2r)* Math.cos(Long2r-Long1r))*R; return d*1000; } private double ConvertDegreeToRadians(double degrees) { return (Math.PI/180)*degrees; } public String format(double num) { NumberFormat formatter = new DecimalFormat("###"); String s=formatter.format(num); return s; } class MyLocationOverlay extends Overlay { public boolean draw(Canvas canvas, MapView mapView, boolean shadow, long when) { super.draw(canvas, mapView, shadow); Paint paint = new Paint(); Point myScreenCoords = new Point(); // 将经纬度转换成实际屏幕坐标 GeoPoint tmpGeoPoint = new GeoPoint((int)(gp2.getLatitudeE6()),(int)(gp2.getLongitudeE6())); mapView.getProjection().toPixels(tmpGeoPoint, myScreenCoords); paint.setFlags(Paint.ANTI_ALIAS_FLAG); paint.setStrokeWidth(5); canvas.drawText(latLongString, myScreenCoords.x+5, myScreenCoords.y, paint); return true; } } @Override protected boolean isRouteDisplayed() { return false; } public boolean onCreateOptionsMenu(Menu menu) { menu.add(0, ViewMode, Menu.NONE, "地图模式").setIcon(R.drawable.viewmode); menu.add(0, Exit, Menu.NONE, "退出").setIcon(R.drawable.exit); return super.onCreateOptionsMenu(menu); } public boolean onOptionsItemSelected(MenuItem item) { super.onOptionsItemSelected(item); switch (item.getItemId()) { case ViewMode: selectViewMode(); return true; case Exit: this.finish(); return true; } return true; } //选择地图模式 public void selectViewMode() { OnClickListener listener = new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int which) { switch ( which ) { case 0: mMapView.setTraffic(false); mMapView.setSatellite(false); mMapView.setStreetView(true); break; case 1: mMapView.setSatellite(false); mMapView.setStreetView(false); mMapView.setTraffic(true); break; case 2: mMapView.setStreetView(false); mMapView.setTraffic(false); mMapView.setSatellite(true); break; } } }; String[] menu={"街景模式","交通流量","卫星地图"}; new AlertDialog.Builder(MapDistance.this) .setTitle("请选择地图模式") .setItems(menu, listener) .show(); } }

 MyOverLay.java 代码

public class MyOverLay extends Overlay { private GeoPoint gp1; private GeoPoint gp2; private int mRadius=6; private int mode=0; /* 建立传入起点中点的mode */ public MyOverLay(GeoPoint gp1,GeoPoint gp2,int mode) { this.gp1 = gp1; this.gp2 = gp2; this.mode = mode; } @Override public boolean draw (Canvas canvas, MapView mapView, boolean shadow, long when) { Projection projection = mapView.getProjection(); if (shadow == false) { Paint paint = new Paint(); paint.setAntiAlias(true); paint.setColor(Color.BLACK); Point point = new Point(); projection.toPixels(gp1, point); if(mode==1) { RectF oval=new RectF(point.x - mRadius, point.y - mRadius, point.x + mRadius, point.y + mRadius); canvas.drawOval(oval, paint); // canvas.drawText(latLongString, point.x+5, point.y, paint); } else if(mode==2) { Point point2 = new Point(); projection.toPixels(gp2, point2); paint.setStrokeWidth(5); paint.setAlpha(120); canvas.drawLine(point.x, point.y, point2.x,point2.y, paint); paint.setAlpha(255); } else if(mode==3) { Point point2 = new Point(); projection.toPixels(gp2, point2); paint.setStrokeWidth(5); paint.setAlpha(120); canvas.drawLine(point.x, point.y, point2.x,point2.y, paint); RectF oval=new RectF(point2.x - mRadius,point2.y - mRadius, point2.x + mRadius,point2.y + mRadius); paint.setAlpha(255); canvas.drawOval(oval, paint); } } return super.draw(canvas, mapView, shadow, when); } }

还要在main.xml用于设Button  TextView ，还要color.xml ,strings.xml中编写相应的代码。要去Google申请个地图的apiKey,方法网上很多。还要在AndroidManifes.xml中添加相应的权限。还要添加相应的图标。

由于没有android的手机没有在手机上对这个程序进行测试真机上测试，在模拟器上能运行能够运行。