android 百度地图 通过剪裁图片添加 Marker

初始化百度地图：

 private void initViews() {
          mMapView = (MapView) findViewById(R.id.bmapView);
         mBaiduMap = mMapView.getMap();
         // 初始化地图范围级别
         MapStatusUpdate msu = MapStatusUpdateFactory.zoomTo(14.0f);
         mBaiduMap.setMapStatus(msu);
     }

--------------------华丽分割线-----------------------

// 初始化bitmap 信息，不用时及时 recycle
BitmapDescriptor friend_1;

初始化剪裁的图片（此处为生成圆形图片）：

 friend_1 = BitmapDescriptorFactory.fromBitmap(
                     BMapUtil.createCircleImage(BitmapFactory.decodeResource(getResources(), R.drawable.friend_1), 90));

圆形图片生成方法：

 /**
      * 根据原图和变长绘制圆形图片
      * @param source
      * @param min
      * @return
      */
     public static Bitmap createCircleImage(Bitmap source, int radius) {
         Bitmap scaledSrcBmp;
         int diameter = radius * 2;
         // 为了防止宽高不相等，造成圆形图片变形，因此截取长方形中处于中间位置最大的正方形图片
         int bmpWidth = source.getWidth();
         int bmpHeight = source.getHeight();
         int squareWidth = 0, squareHeight = 0;
         int x = 0, y = 0;
         Bitmap squareBitmap;
         if (bmpHeight > bmpWidth) {// 高大于宽
             squareWidth = squareHeight = bmpWidth;
             x = 0;
             y = (bmpHeight - bmpWidth) / 2;
             // 截取正方形图片
             squareBitmap = Bitmap.createBitmap(source, x, y, squareWidth,
                     squareHeight);
         } else if (bmpHeight < bmpWidth) {// 宽大于高
             squareWidth = squareHeight = bmpHeight;
             x = (bmpWidth - bmpHeight) / 2;
             y = 0;
             squareBitmap = Bitmap.createBitmap(source, x, y, squareWidth,
                     squareHeight);
         } else {
             squareBitmap = source;
         }
         if (squareBitmap.getWidth() != diameter
                 || squareBitmap.getHeight() != diameter) {
             scaledSrcBmp = Bitmap.createScaledBitmap(squareBitmap, diameter,
                     diameter, true);
         } else {
             scaledSrcBmp = squareBitmap;
         }
         Bitmap output = Bitmap.createBitmap(scaledSrcBmp.getWidth(),
                 scaledSrcBmp.getHeight(), Config.ARGB_8888);
         Canvas canvas = new Canvas(output);

         Paint paint = new Paint();
         Rect rect = new Rect(0, 0, scaledSrcBmp.getWidth(),
                 scaledSrcBmp.getHeight());

         paint.setAntiAlias(true);
         paint.setFilterBitmap(true);
         paint.setDither(true);
         canvas.drawARGB(0, 0, 0, 0);
         canvas.drawCircle(scaledSrcBmp.getWidth() / 2,
                 scaledSrcBmp.getHeight() / 2, scaledSrcBmp.getWidth() / 2,
                 paint);
         paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
         canvas.drawBitmap(scaledSrcBmp, rect, rect, paint);
         bmp = null;
         squareBitmap = null;
         scaledSrcBmp = null;
         return output;
     }

初始化位置信息：

 LatLng position_1 = new LatLng(39.963175, 116.400244);

初始化OverlayOptions：

 OverlayOptions ooA = new MarkerOptions().position(position_1).icon(friend_1)
                 .zIndex(9).draggable(true);

再通过addOverlay添加到地图：

 mMarkerA = (Marker) (mBaiduMap.addOverlay(ooA));

注册setOnMarkerClickListener：

mBaiduMap.setOnMarkerClickListener(new OnMarkerClickListener() {
            public boolean onMarkerClick(final Marker marker) {
       // todo 判断mMarkerA 的点击事件
   }
}

当退出时，释放资源：

@Override
    protected void onPause() {
        // MapView的生命周期与Activity同步，当activity挂起时需调用MapView.onPause()
        mMapView.onPause();
        super.onPause();
    }

    @Override
    protected void onResume() {
        // MapView的生命周期与Activity同步，当activity恢复时需调用MapView.onResume()
        mMapView.onResume();
        super.onResume();
    }

    @Override
    protected void onDestroy() {
        // MapView的生命周期与Activity同步，当activity销毁时需调用MapView.destroy()
        mMapView.onDestroy();
        super.onDestroy();
        // 回收 bitmap 资源
        friend_1.recycle();
    }