//protected override Size MeasureOverride(Size availableSize)
//{
// bool bNeedUpdate = false;
// if (m_bufferedBmp != null && m_ptOffset.X + (int)ActualWidth > ExtentWidth)
// {
// bNeedUpdate = true;
// m_ptOffset.X = ExtentWidth - (int)ActualWidth;
// if (m_ptOffset.X < 0)
// m_ptOffset.X = 0;
// }
// if (bNeedUpdate)
// {
// paintArea(new GDI.Rectangle(0, 0, m_bufferedBmp.PixelWidth, m_bufferedBmp.PixelHeight));
// Invalidate();
// }
// return base.MeasureOverride(availableSize);
//}
internal void SetHorizontalOffset(double offset)
{
offset = (int)offset;
// 这里产生了水平滚动，识别哪些数据可以使用就只需copy一下就可以了
int OffsetX = (int)Math.Abs(m_ptOffset.X - offset);
if (OffsetX < ActualWidth - 20) // 说明是可以使用部分数据的， -20是如果只有20象素宽可用的话，那也没意义了，直接刷新效率更好
{
if (m_ptOffset.X < offset)
{
GB_GridView.Bitblt(m_bufferedBmp, new GDI.Rectangle(OffsetX, 0, (int)ActualWidth - OffsetX, (int)ActualHeight),
new GDI.Rectangle(0, 0, (int)ActualWidth - OffsetX, (int)ActualHeight));
m_ptOffset.X = offset;
paintArea(new GDI.Rectangle((int)ActualWidth - OffsetX, 0, OffsetX, (int)ActualHeight));
}
else
{
GB_GridView.Bitblt(m_bufferedBmp, new GDI.Rectangle(0, 0, (int)m_bufferedBmp.PixelWidth - OffsetX, (int)m_bufferedBmp.PixelHeight),
new GDI.Rectangle(OffsetX, 0, (int)m_bufferedBmp.PixelWidth - OffsetX, (int)m_bufferedBmp.PixelHeight));
m_ptOffset.X = offset;
paintArea(new GDI.Rectangle(0, 0, OffsetX, (int)m_bufferedBmp.PixelHeight));
}
}
else
{
m_ptOffset.X = offset;
paintArea(new GDI.Rectangle(0, 0, (int)m_bufferedBmp.PixelWidth, (int)m_bufferedBmp.PixelHeight));
}
m_bufferedBmp.Lock();
m_bufferedBmp.AddDirtyRect(new Int32Rect(0, 0, m_bufferedBmp.PixelWidth, m_bufferedBmp.PixelHeight));
m_bufferedBmp.Unlock();
}
public void BitBlt(GDI.Rectangle rectSrc, GDI.Rectangle rectDest)
{
GB_GridView.Bitblt(m_bufferedBmp, rectSrc, rectDest);
}
