private bool TabToNextControl(Control focus,
bool forward)
{
// Start searching from the current focus control
Control next = focus;
// If only allow focus on a control within the page instance, so
// setting to null will force the GetNextControl to get the first
// child control of the page.
if (!_page.Contains(next))
{
next = null;
}
// Have we wrapped around the end yet?
bool wrapped = false;
do
{
// Find the next control in sequence
next = _page.GetNextControl(next, forward);
// If no more controls found, then finished
if (next == null)
{
// If already wrapped around end of list then must be finished
if (wrapped)
{
return(false);
}
// Keep going from the start
wrapped = true;
}
else
{
// Can only selected controls that are inside ourself as a container
if (_page.Contains(next))
{
// If the next control is allowed to become selected
// and allowed to be selected because of a tab action
if (next.CanSelect && next.TabStop)
{
// Is the next control a container control?
if (next is ContainerControl)
{
// If the source control of the next/previous is inside the container
// then we do not want to stop at the container itself as that would
// just put the focus straight back into the container. So keep going.
if (!next.Contains(focus))
{
// We need to call the protected select method in order to have
// it perform an internal select of the first/last ordered item
_containerSelect.Invoke(next, new object[] { true, forward });
return(true);
}
}
else
{
// Select the actual control
if (!_page.ContainsFocus)
{
next.Focus();
}
else
{
next.Select();
}
return(true);
}
}
}
}
}while (next != focus);
// We always override processing of this method
return(true);
}