在android中绘制圆圈和比例框

Question

Display image

在我的应用程序中，我想绘制一些几何形状，如圆形，矩形。当我拖动时，应该如图所示绘制圆圈。当我选择圆圈时，我应该能够移动并调整圆形大小。根据我的要求查看图片。现在我只能画圆圈了。如何在圆圈周围获得缩放框？帮助我。

@覆盖     public boolean onTouchEvent（MotionEvent event）{

    boolean handled = false;
    int pointerId;
    int actionIndex = event.getActionIndex();

    switch (event.getActionMasked()) {

        case MotionEvent.ACTION_DOWN:

            clearCirclePointer();

            mStartX = (int) event.getX();
            mStartY = (int) event.getY();
            break;

        case MotionEvent.ACTION_MOVE:

            pointerId = event.getPointerId(actionIndex);

            mMidPointX = (int) ((event.getX() + mStartX) / 2);
            mMidPointY = (int) ((event.getY() + mStartY) / 2);

            mRadius = (int) Math.sqrt((Math.pow(mMidPointX - mStartX, 2) + Math.pow(mMidPointY - mStartY, 2)));

            mPaint.setPathEffect(dashPath);

            invalidate();

            handled = true;

            break;

        case MotionEvent.ACTION_UP:

            mEndX = (int) event.getX();
            mEndY = (int) event.getY();

            mMidPointX = ((mEndX + mStartX) / 2);
            mMidPointY = ((mEndY + mStartY) / 2);

            mRadius = (int) Math.sqrt((Math.pow(mMidPointX - mStartX, 2) + Math.pow(mMidPointY - mStartY, 2)));

            mPaint.setPathEffect(solidPath);

            mCircle.setxAxis(mMidPointX);
            mCircle.setyAxis(mMidPointY);
            mCircle.setRadius(mRadius);
            mCircle.setPaint(mPaint);

            mCirclePointer.put(event.getPointerId(0), mCircle);

            invalidate();

            break;

        case MotionEvent.ACTION_CANCEL:

            handled = true;

            break;

        default:

            break;
    }

    return super.onTouchEvent(event) || handled;
}

@Override
protected void onDraw(Canvas canvas) {

    super.onDraw(canvas);

     for (Circle circle : mCircleSet) {

         if (mCircleSet == null || mCircleSet.size() == 0)
             return;

        canvas.drawCircle(circle.getxAxis(), circle.getyAxis(), circle.getRadius(), circle.getPaint());
    }
}