两个坐标间画线

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    linearLayout = (LinearLayout) findViewById(R.id.zoomview);
    mapView = (MapView) findViewById(R.id.mapview);
    mapView.setBuiltInZoomControls(true);

    mapOverlays = mapView.getOverlays();        
    projection = mapView.getProjection();
    mapOverlays.add(new MyOverlay());        

}

@Override
protected boolean isRouteDisplayed() {
    return false;
}

class MyOverlay extends Overlay{

    public MyOverlay(){

    }   

    public void draw(Canvas canvas, MapView mapv, boolean shadow){
        super.draw(canvas, mapv, shadow);

        mPaint = new Paint();
        mPaint.setDither(true);
        mPaint.setColor(Color.RED);
        mPaint.setStyle(Paint.Style.FILL_AND_STROKE);
        mPaint.setStrokeJoin(Paint.Join.ROUND);
        mPaint.setStrokeCap(Paint.Cap.ROUND);
        mPaint.setStrokeWidth(2);

        GeoPoint gP1 = new GeoPoint(19240000,-99120000);
        GeoPoint gP2 = new GeoPoint(37423157, -122085008);

        Point p1 = new Point();
        Point p2 = new Point();

        path = new Path();

        projection.toPixels(gP1, p1);
        projection.toPixels(gP2, p2);

        path.moveTo(p2.x, p2.y);
        path.lineTo(p1.x,p1.y);

        canvas.drawPath(path, mPaint);
    }