android - onTap 如何在 android mapview 中工作

Question

onTap 监听器如何在 android map View 中工作，即使 map View 已移动。实际上，我正在根据用户方向旋转 map View 。

我正在从 sesor 经理那里获取方位角。

如果角度为 0，则 onTap 在 Pin 上正常工作。如果角度发生变化，比如 20 onTap 在 pin 上不能准确工作，它会在 pin 旁边工作一段时间后。

我在里面使用了旋转 View ，我使用了 mapview。现在我在方位改变后旋转 rotateview。

RotateView设置方位代码

 @Override
    protected void dispatchDraw(Canvas canvas) {

        canvas.save(Canvas.MATRIX_SAVE_FLAG);

    //if mHeading is zero its work otherwise onTap position is changing 
        canvas.rotate(mHeading, getWidth()/2, getHeight());

        mCanvas.delegate = canvas;
        super.dispatchDraw(mCanvas);
        canvas.restore();
    }

覆盖类

public class SonarOverlay1 extends ItemizedOverlay<OverlayItem>
{
    private ArrayList<OverlayItem> mOverlays = new ArrayList<OverlayItem>();
    private Context mContext;
public SonarOverlay1(Drawable defaultMarker,Context context) {
    super(boundCenter(defaultMarker));
    this.mContext=context;

    populate();
}

@Override
protected OverlayItem createItem(int arg0) {

    return  mOverlays.get(arg0);
}
public void addOverlay(OverlayItem item) {
    mOverlays.add(item);
    populate();

}

@Override
public int size() {
//Log.e("overlay size..",""+mOverlays.size());
    return mOverlays.size();
}


@Override
protected boolean onTap(int index) {
    // TODO Auto-generated method stub

      OverlayItem item = mOverlays.get(index);
      AlertDialog.Builder dialog = new AlertDialog.Builder(mContext);
      dialog.setTitle(item.getTitle());
      dialog.setMessage(item.getSnippet());
      dialog.show();
      return true;
}
}

Answer 1

这里在旋转 map 时我们必须使用 onDispatchTouch 方法连同 map 一起旋转触摸事件

看下面的代码

@Override
    public boolean dispatchTouchEvent(MotionEvent event) {
        float[] coords = new float[] {
                event.getX(), event.getY()
        };
        adjustCoords(coords, getRotation());
        MotionEvent evt = MotionEvent.obtain(event.getDownTime(), event.getEventTime(), event
                .getAction(), coords[0], coords[1], event.getPressure(), event.getSize(), event
                .getMetaState(), event.getXPrecision(), event.getYPrecision(), event.getDeviceId(),
                event.getEdgeFlags());
        return super.dispatchTouchEvent(evt);
    }
    protected void adjustCoords(float[] coords, float deg) {
        float x = coords[0];
        float y = coords[1];
        int centerX = getWidth() / 2;
        int centerY = getHeight() / 2;
        // convert to radians
        float rad = (float) ((deg * Math.PI) / 180F);
        float s = (float) Math.sin(rad);
        float c = (float) Math.cos(rad);
        // translate point back to origin:
        x -= centerX;
        y -= centerY;
        // apply rotation
        float tmpX = x * c - y * s;
        float tmpY = x * s + y * c;
        x = tmpX;
        y = tmpY;
        // translate point back:
        x += centerX;
        y += centerY;
        coords[0] = x;
        coords[1] = y;
    }

请引用以下链接

How to manage overlays in MapViewCompassDemo in android sdk samples