我使用的是标签视图库。但是当我尝试缩放标签视图时，视图会稍微向左旋转。下面是视图的ontouchevent代码。请帮我解决这个问题。

private OnTouchListener mTouchListener = new OnTouchListener() {
    @Override
    public boolean onTouch(View view, MotionEvent event) {

            switch (event.getAction()) {
                case MotionEvent.ACTION_DOWN:
                    Log.v(TAG, "iv_scale action down");

                    this_orgX = StickerView.this.getX();
                    this_orgY = StickerView.this.getY();

                    scale_orgX = event.getRawX();
                    scale_orgY = event.getRawY();
                    scale_orgWidth = StickerView.this.getLayoutParams().width;
                    scale_orgHeight = StickerView.this.getLayoutParams().height;

                    rotate_orgX = event.getRawX();
                    rotate_orgY = event.getRawY();

                    centerX = StickerView.this.getX()+
                            ((View)StickerView.this.getParent()).getX()+
                            (float)StickerView.this.getWidth()/2;

                    //double statusBarHeight = Math.ceil(25 * getContext().getResources().getDisplayMetrics().density);
                    int result = 0;
                    int resourceId = getResources().getIdentifier("status_bar_height", "dimen", "android");
                    if (resourceId > 0) {
                        result = getResources().getDimensionPixelSize(resourceId);
                    }
                    double statusBarHeight = result;
                    centerY = StickerView.this.getY()+
                            ((View)StickerView.this.getParent()).getY()+
                            statusBarHeight+
                            (float)StickerView.this.getHeight()/2;

                    break;
                case MotionEvent.ACTION_MOVE:
                    Log.v(TAG, "iv_scale action move");

                    rotate_newX = event.getRawX();
                    rotate_newY = event.getRawY();

                    double angle_diff = Math.abs(
                            Math.atan2(event.getRawY() - scale_orgY , event.getRawX() - scale_orgX)
                                    - Math.atan2(scale_orgY - centerY, scale_orgX - centerX))*180/Math.PI;

                    Log.v(TAG, "angle_diff: "+angle_diff);

                    double length1 = getLength(centerX, centerY, scale_orgX, scale_orgY);
                    double length2 = getLength(centerX, centerY, event.getRawX(), event.getRawY());

                    int size = convertDpToPixel(SELF_SIZE_DP, getContext());
                    if(length2 > length1
                            && (angle_diff < 25 || Math.abs(angle_diff-180)<25)
                            ) {
                        //scale up
                        double offsetX = Math.abs(event.getRawX() - scale_orgX);
                        double offsetY = Math.abs(event.getRawY() - scale_orgY);
                        double offset = Math.max(offsetX, offsetY);
                        offset = Math.round(offset);
                        StickerView.this.getLayoutParams().width += offset;
                        StickerView.this.getLayoutParams().height += offset;
                        onScaling(true);
                        //DraggableViewGroup.this.setX((float) (getX() - offset / 2));
                        //DraggableViewGroup.this.setY((float) (getY() - offset / 2));
                    }else if(length2 < length1
                            && (angle_diff < 25 || Math.abs(angle_diff-180)<25)
                            && StickerView.this.getLayoutParams().width > size/2
                            && StickerView.this.getLayoutParams().height > size/2) {
                        //scale down
                        double offsetX = Math.abs(event.getRawX() - scale_orgX);
                        double offsetY = Math.abs(event.getRawY() - scale_orgY);
                        double offset = Math.max(offsetX, offsetY);
                        offset = Math.round(offset);
                        StickerView.this.getLayoutParams().width -= offset;
                        StickerView.this.getLayoutParams().height -= offset;
                        onScaling(false);
                    }

                    //rotate

                    double angle = Math.atan2(event.getRawY() - centerY, event.getRawX() - centerX) * 180 / Math.PI;
                    Log.v(TAG, "log angle: " + angle);

                    //setRotation((float) angle - 45);
                    setRotation((float) angle - 45);
                    Log.v(TAG, "getRotation(): " + getRotation());

                    onRotating();

                    rotate_orgX = rotate_newX;
                    rotate_orgY = rotate_newY;

                    scale_orgX = event.getRawX();
                    scale_orgY = event.getRawY();

                    postInvalidate();
                    requestLayout();
                    break;
                case MotionEvent.ACTION_UP:
                    Log.v(TAG, "iv_scale action up");
                    break;
            }

        return true;
    }
};

正如你在调用setrotation方法的代码中看到的，他在减去45度，我认为这是导致问题的原因。我试着玩那个号码，但还是忍不住。所以我来这里寻求帮助。