package cn.bhc.drawline;
import java.util.List;
import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapActivity;
import com.google.android.maps.MapView;
import com.google.android.maps.Overlay;
import com.google.android.maps.Projection;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Point;
import android.graphics.drawable.BitmapDrawable;
import android.os.Bundle;
public class DrawLineTestActivity extends MapActivity {
private MapView mapView;
private List <Overlay> mapOverlays;
private Projection projection;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mapView = (MapView) findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true);
mapOverlays = mapView.getOverlays();
projection = mapView.getProjection();
mapOverlays.add(new MyOverlay());
}
@Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
class MyOverlay extends Overlay{
public MyOverlay(){
}
public void draw(Canvas canvas, MapView mapv, boolean shadow){
super.draw(canvas, mapv, shadow);
Paint 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);
GeoPoint gP3=new GeoPoint(37500000, -14000000);
GeoPoint gp4=new GeoPoint(38500005, -16005555);
Point p1 = new Point();
Point p2 = new Point();
Point p3=new Point();
Point p4=new Point();
Path path = new Path();
projection.toPixels(gP1, p1);
projection.toPixels(gP2, p2);
projection.toPixels(gP3, p3);
projection.toPixels(gp4, p4);
path.moveTo(p2.x, p2.y);
path.lineTo(p1.x,p1.y);
path.moveTo(p1.x, p1.y);
path.lineTo(p3.x, p3.y);
path.moveTo(p3.x, p3.y);
path.lineTo(p4.x,p4.y);
canvas.drawPath(path, mPaint);
path.moveTo(p2.x, p2.y);
Bitmap bitmap=((BitmapDrawable)getResources().getDrawable(R.drawable.flag)).getBitmap();
canvas.drawBitmap(bitmap, p2.x, p2.y,mPaint);
}
}
}
问题：
1.问什么我画出的线左右来回拖动就会变形了，不是固定的？？
2.为什么我在地图上p2处画的那个图标老是显示不到p2处，我把p2换成其他三个点，同样也显示不到正确的位置，这是怎么回事，请高手们给我解答下啊，谢谢了，很迷惑也很急啊！！！
------解决方案--------------------
1.应该和你给出的坐标有关系，当跨时区分割线时，系统会自动判定，以保证画线最大范围显示出来；
2.显示不到P2点上，因为绘制的图片的左上角为你所给的点，所以貌似没有到正确的位置，你放大到最大，看下，是不是这样，可以计算下img的宽高来让它显示在中央位置。