You can have the combobox auto drop as your user types by handling this event. This way he can use the arrow keys without further work on your part.
bool inStartEditing = false;
private void gridControl1_CurrentCellStartEditing(object sender, CancelEventArgs e)
{
GridCurrentCell cc = this.gridControl1.CurrentCell;
if(!inStartEditing && cc.Renderer is GridComboBoxCellRenderer
)
{
inStartEditing = true;
cc.ShowDropDown();
inStartEditing = false;
}
}
If auto dropping the combobox does not serve your needs, then you would have to code this yourself. You could derive a custom cell control to handle this. I am not sure whether you would want to try to derive from our combobox or do something different depending upon whether you ever want dropdown support in this cell.