Image.addListener(new DragListener() {
            public void drag(InputEvent event, float x, float y, int pointer) {
                float lastPosX, lastPosY;
                lastPosX = event.getStageX();
                lastPosY = event.getStageY();
                Image.moveBy(event.getStageX() - lastPosX, event.getStageY() - lastPosY);
                lastPosX = event.getStageX();
                lastPosY = event.getStageY();
            }
        });