protected override void OnDrawItem(DrawItemEventArgs e)
{
int index = e.Index;
if (index > -1)
{
e.DrawBackground();
IEnableableComboBoxItem item = Items[index] as IEnableableComboBoxItem;
Color textColor = SystemColors.ControlText;
//Paint disabled items grey - otherwise leave them black
if (item != null && !item.Enabled)
{
textColor = SystemColors.GrayText;
}
if ((e.State & DrawItemState.Selected) == DrawItemState.Selected)
{
textColor = SystemColors.HighlightText;
}
Drawing.DrawText(e.Graphics, Items[index].ToString(), Font, e.Bounds.Location, textColor);
}
base.OnDrawItem(e);
}
private IntPtr ReplacementWndProc(IntPtr hWnd, uint msg, IntPtr wParam, IntPtr lParam)
{
if (msg == (uint)Win32.WM_LBUTTONDOWN || msg == (uint)Win32.WM_LBUTTONDBLCLK)
{
Win32.POINT loc = new Win32.POINT();
loc.X = MousePosition.X;
loc.Y = MousePosition.Y;
Win32.ScreenToClient(DropDownHandle, ref loc);
Win32.RECT dropdown_rect = new Win32.RECT();
Win32.GetClientRect(DropDownHandle, out dropdown_rect);
if (dropdown_rect.Left <= loc.X && loc.X < dropdown_rect.Right && dropdown_rect.Top <= loc.Y && loc.Y < dropdown_rect.Bottom)
{
int index = (int)Win32.SendMessage(DropDownHandle, Win32.LB_ITEMFROMPOINT, IntPtr.Zero, (IntPtr)(loc.X + (loc.Y << 16)));
if (index >> 16 == 0)
{
Object o = Items[index];
IEnableableComboBoxItem enableableComboBoxItem = o as IEnableableComboBoxItem;
if (enableableComboBoxItem != null && !enableableComboBoxItem.Enabled)
{
return(IntPtr.Zero);
}
}
}
}
return(Win32.CallWindowProc(oldWndProc, hWnd, msg, wParam, lParam));
}
private void m_comboBoxConnection_DrawItem(object sender, DrawItemEventArgs e)
{
e.DrawBackground();
ComboBox cb = (ComboBox)sender;
int index = e.Index;
if (index > -1 && cb != null)
{
IEnableableComboBoxItem item = cb.Items[index] as IEnableableComboBoxItem;
using (SolidBrush textBrush = new SolidBrush(SystemColors.ControlText))
{
//Paint disabled items grey - otherwise leave them black
if (item != null && !item.Enabled)
{
textBrush.Color = SystemColors.GrayText;
}
if ((e.State & DrawItemState.Selected) == DrawItemState.Selected)
{
textBrush.Color = SystemColors.HighlightText;
}
e.Graphics.DrawString(cb.Items[index].ToString(), ((Control)sender).Font, textBrush, e.Bounds.X, e.Bounds.Y);
}
}
}
protected override void OnSelectedIndexChanged(EventArgs e)
{
int i = SelectedIndex;
if (i == -1 || AllItemsDisabled())
{
return;
}
if (!(Items[i] is IEnableableComboBoxItem))
{
base.OnSelectedIndexChanged(e);
return;
}
while (true)
{
if (i == 0)
{
skip = true;
}
else if (i == Items.Count - 1)
{
skip = false;
}
IEnableableComboBoxItem item = Items[i] as IEnableableComboBoxItem;
if (item != null && !item.Enabled)
{
i += skip ? 1 : -1;
}
else
{
skip = true;
break;
}
}
if (SelectedIndex != i)
{
//Calling this resends the event - you don't want to call the base
//event or any registered handlers will be triggered twice
SelectedIndex = i;
return;
}
base.OnSelectedIndexChanged(e);
}
