I've poured over the docs and haven't been able to figure this out. Is it even possible?
It looks like the correct mechanism to do this is to extend MyLocationOverlay then override the drawMyLocation() protected method.
The following uses an arrow to show where "you" are and which way "you" are pointing:
package com.example;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Point;
import android.location.Location;
import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapView;
import com.google.android.maps.MyLocationOverlay;
public class MyCustomLocationOverlay extends MyLocationOverlay {
private Context mContext;
private float mOrientation;
public MyCustomLocationOverlay(Context context, MapView mapView) {
super(context, mapView);
mContext = context;
}
@Override
protected void drawMyLocation(Canvas canvas, MapView mapView, Location lastFix, GeoPoint myLocation, long when) {
// translate the GeoPoint to screen pixels
Point screenPts = mapView.getProjection().toPixels(myLocation, null);
// create a rotated copy of the marker
Bitmap arrowBitmap = BitmapFactory.decodeResource( mContext.getResources(), R.drawable.arrow_green);
Matrix matrix = new Matrix();
matrix.postRotate(mOrientation);
Bitmap rotatedBmp = Bitmap.createBitmap(
arrowBitmap,
0, 0,
arrowBitmap.getWidth(),
arrowBitmap.getHeight(),
matrix,
true
);
// add the rotated marker to the canvas
canvas.drawBitmap(
rotatedBmp,
screenPts.x - (rotatedBmp.getWidth() / 2),
screenPts.y - (rotatedBmp.getHeight() / 2),
null
);
}
public void setOrientation(float newOrientation) {
mOrientation = newOrientation;
}
}
I made a few changes to the previuos code in order to get it to work properly because the arrow was pointing to the wrong direction and rotating in the opposite direction.
I changed
matrix.postRotate(mOrientation);
for
matrix.postRotate(this.getRotation());
and added to the end:
mapView.postInvalidate();
to redraw the arrow when it changes
来源:https://stackoverflow.com/questions/753793/how-can-i-use-a-custom-bitmap-for-the-you-are-here-point-in-a-mylocationoverla