一、根据当前的需要来继承相应的控件，已便减少重复开发

一般继承 DoPaint来写，若需要在最上层显示的，则要继承DoPostPaint()

例读取图片旋转显示，配合GDI+来，注意Gdiplus::Bitmap的构造函数，本例PNG，使用PixelFormat32bppPARGB

bool RotateAnimation::DoPaint(HDC hDC, const RECT& rcPaint, CControlUI* pStopControl)
{
		Gdiplus::PointF centerPos(m_rcItem.left + GetWidth()/ 2, m_rcItem.top + GetHeight()/ 2);

		Gdiplus::Graphics graphics(hDC);
		//graphics.SetSmoothingMode(SmoothingModeAntiAlias);

		graphics.TranslateTransform(centerPos.X, centerPos.Y);
		graphics.RotateTransform(m_fCurAngle);
		graphics.TranslateTransform(-centerPos.X, -centerPos.Y);

		const TImageInfo* imgInfo = GetManager()->GetImageEx(m_diBk.sImageName);
		BITMAP bmp;
		GetObject(imgInfo->hBitmap, sizeof(BITMAP), &bmp);		
		Gdiplus::Bitmap gdi_bmp(imgInfo->nX, imgInfo->nY, imgInfo->nX * 4, PixelFormat32bppPARGB, (BYTE*)bmp.bmBits);
	
		graphics.DrawImage(&gdi_bmp, m_rcItem.left, m_rcItem.top, GetWidth(), GetHeight());
		return true;
	}	
}

再细看一下DoPostPaint，首先要加入m_aPostPaintControls这个数组，在所有控件都被paint完成后，最后调用之，所以，它比DoPaint更在最上层

查看Duilib的源码的时候，都可以看到