在Google地图上绘制直线
?mars chen 老师第三季视频 08集
绘制路线的步骤
? 1.确定路线的起始和终止的经纬度坐标
??2在起点和终点上绘制图标
? 3将经纬度坐标换算成屏幕上x轴/y轴坐标
? 4在起点和终点绘制直线
代码如下：
public class MainActivity extends MapActivity {private GeoPoint beginGeoPoint;private GeoPoint endGeoPoint;private MapController mapController;private List<Overlay> overlays;private Projection projection;@Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); //指定起始和终止位置经纬度 beginGeoPoint=new GeoPoint(19240000,-99120000); endGeoPoint=new GeoPoint(19340000,-99220000); MapView mapView=(MapView)findViewById(R.id.mapview); mapView.setBuiltInZoomControls(true); //对地图进行控制 mapController=mapView.getController(); overlays=mapView.getOverlays(); projection=mapView.getProjection(); overlays.add(new PointOverlay(beginGeoPoint)); overlays.add(new PointOverlay(endGeoPoint)); overlays.add(new LineOverlay(beginGeoPoint,endGeoPoint)); // mapController.animateTo(beginGeoPoint); mapController.setZoom(12); }@Overrideprotected boolean isRouteDisplayed() {return false;}//该类对象用于在地图上绘制线条 class LineOverlay extends Overlay{private GeoPoint begin;private GeoPoint end;public LineOverlay() {}public LineOverlay(GeoPoint begin, GeoPoint end) {this.begin = begin;this.end = end;}//canvas画布 paint画笔@Overridepublic void draw(Canvas canvas, MapView mapView, boolean shadow) {super.draw(canvas, mapView, shadow);Paint paint=new Paint();paint.setColor(Color.BLUE);paint.setStyle(Paint.Style.FILL_AND_STROKE);paint.setStrokeWidth(2);Point beginPoint=new Point();Point endPoint=new Point();Path path=new Path();projection.toPixels(beginGeoPoint,beginPoint);projection.toPixels(endGeoPoint, endPoint);path.moveTo(endPoint.x, endPoint.y);path.lineTo(beginPoint.x, beginPoint.y);canvas.drawPath(path, paint);}}//绘制图标class PointOverlay extends Overlay{private GeoPoint geoPoint;public PointOverlay() {}public PointOverlay(GeoPoint geoPoint) {super();this.geoPoint = geoPoint;}@Overridepublic void draw(Canvas canvas, MapView mapView, boolean shadow) {super.draw(canvas, mapView, shadow);Point point=new Point();projection.toPixels(geoPoint,point);Bitmap bmp=BitmapFactory.decodeResource(getResources(), R.drawable.tool);Paint paint=new Paint();canvas.drawBitmap(bmp, point.x, point.y-10,paint);}}}?
效果图：
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?最近有点忙，等有时间了。一定好好琢磨琢磨，写个漂亮实用的地图出来。先记录下来，备忘。
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