MFC: Adding CListView tab to a CTabView (CBCGPTabView) on request doesn't call CMyListView::OnInitialUpdate() - mfc

Question

I have a CMyTabView derived from CBCGPTabView (CTabView) that I want to add tabs to on the fly. The tab being added will be a CMyListView derived from CListView. If I add the tab during CMyTabView::OnCreate() it works fine. If I try to do it via a custom message, it adds the tab, but it's blank (CMyListView::OnInitialUpdate() is never called).
What do I need to do for it to work?
Here's what works (the test tab):
int CMyTabView::OnCreate(LPCREATESTRUCT lpCreateStruct)
{
if (__super::OnCreate(lpCreateStruct) == -1)
return -1;
CBCGPTabWnd &tabctrl=GetTabControl();
int index=AddView(RUNTIME_CLASS(CMyForm), _T("My Form"));
if (index!=-1) {
m_IDTabMyForm=tabctrl.GetTabID(index);
}
AddView(RUNTIME_CLASS(CMyListView), _T("Test"));
tabctrl.HideNoTabs();
return 0;
}
This doesn't (other than adding the tab with a blank window).
afx_msg LRESULT CMyTabView::OnUwmAddMyListViewTab(WPARAM wparam, LPARAM lparam)
{
CString mytabname;
mytabname=_T("My ListView");
// check if tab already exists - if so select it
CBCGPTabWnd &tabcontrol=GetTabControl();
for (int i=0; i<tabcontrol.GetTabsNum(); i++) {
CString tablabel;
if (tabcontrol.GetTabLabel(i, tablabel)) {
if (tablabel==mytabname) {
tabcontrol.SetActiveTab(i);
return 0;
}
}
}
// new tab so add it
int index=AddView(RUNTIME_CLASS(CMyListView), mytabname);
if (index!=-1) {
tabcontrol.SetActiveTab(index);
}
return 0;
}

Answer 1

It turns out you have to call it yourself, version below works:
afx_msg LRESULT CMyTabView::OnUwmAddMyListViewTab(WPARAM wparam, LPARAM lparam)
{
CString mytabname;
mytabname=_T("My ListView");
// check if tab already exists - if so select it
CBCGPTabWnd &tabcontrol=GetTabControl();
for (int i=0; i<tabcontrol.GetTabsNum(); i++) {
CString tablabel;
if (tabcontrol.GetTabLabel(i, tablabel)) {
if (tablabel==mytabname) {
tabcontrol.SetActiveTab(i);
return 0;
}
}
}
// new tab so add it
int index=AddView(RUNTIME_CLASS(CMyListView), mytabname);
if (index!=-1) {
CView* thetabview=GetView(index);
if (thetabview) {
// we need to call OnInitUpdate ourself
thetabview->SendMessage(WM_INITIALUPDATE);
//make sure any child windows of the view get the message too
thetabview->SendMessageToDescendants(WM_INITIALUPDATE, 0, 0, TRUE, TRUE);
}
tabcontrol.SetActiveTab(index);
}
return 0;
}