.NET : Smooth Scrolling Panel
Windows raises ThumbTrack ScrollEvent while dragging Scrollbar. And if your System Visual Effects are optimized for performance, window contents are updated only when scollbar stops ( unlike browser)- that looks ugly and annoying.
To solve this I just substituted all SB_THUMBTRACK messeges with SB_THUMBPOSITION. Not very pretty, but works. The following code is in C#.
public class ScrollPanel : System.Windows.Forms.Panel
{
private const int WM_HSCROLL = 0×114;
private const int WM_VSCROLL = 0×115;
protected override void WndProc (ref Message m)
{
if ((m.Msg == WM_HSCROLL || m.Msg == WM_VSCROLL)
&& (((int)m.WParam & 0xFFFF) == 5))
{
// Change SB_THUMBTRACK to SB_THUMBPOSITION
m.WParam = (IntPtr)(((int)m.WParam & ~0xFFFF) | 4);
}
base.WndProc (ref m);
}
}
Can you please help me on your smooth scrolling example. or send me the example project ? basically im using compact framework and have panel with conrols on it… and i have a vScrollBar control and i want to make the scrolling smooth not choppy repaint. thanks a million