Resizable child "ImGui" - imgui

I'm having a problem with my project where I can't get my ImGui::Beginchild to be resizable like ImGui::Begin()
I found other ways to do this but it was not to my liking: https://github.com/ocornut/imgui/issues/319
EXAMPLE CODE :
ui::Begin("title"){
ui::BeginChild("child title", child_size);// resize this child_size when i click the bottom of the child and move
{
ui:Text("example");
}
ui::EndChild();
}
ui::End();

Related

Closing Popup and setting button label

I'm writing a C++ wxWidgets calculator application. I want to compress trigonometric function buttons into a single one to save on space, using what's basically a split button. If you left click on it, the current option is used. If you right click, a popup menu is opened, which contains all the buttons; when you click on one of them, it is used and the big button changes.
I've been suggested to use wxComboBox and other stuff for this job, but I preferred using wxPopupTransientWindow because this way I can display the buttons in a grid, making everything - in my opinion - neater.
Problem is, when I choose an option from the menu, the main button's ID changes (because when I reopen the menu the previously clicked button is light up as its ID and the big button's ID match), but the label does not. Furthermore, the popup is supposed to close itself when you left click on one of the buttons, but it does not.
This is the code for the custom button in the popup which is supposed to do all that stuff:
void expandButton::mouseReleased(wxMouseEvent& evt)
{
if (pressed) {
pressed = false;
paintNow();
wxWindow* mBtn = this->GetParent()->GetParent();
mBtn->SetLabel(this->GetLabel());
mBtn->SetId(this->GetId());
this->GetParent()->Close(true);
}
}
This is the code for the custom button in the main frame which opens up the popup (temporary setup just to test if the whole thing is working):
void ikeButton::rightClick(wxMouseEvent& evt) // CREA PANNELLO ESTENSIONE
{
if (flags & EXPANDABLE)
{
std::vector<expandMenuInfo> buttons;
buttons.push_back(expandMenuInfo(L"sin", 3001));
buttons.push_back(expandMenuInfo(L"cos", 3002));
buttons.push_back(expandMenuInfo(L"tan", 3003));
buttons.push_back(expandMenuInfo(L"arcsin", 3004));
buttons.push_back(expandMenuInfo(L"arccos", 3005));
buttons.push_back(expandMenuInfo(L"arctan", 3006));
wxPoint p = this->GetScreenPosition();
size_t sz = this->GetSize().GetHeight() / 1.15;
expandMenu* menu = new expandMenu(this, buttons, sz, wxPoint(
p.x, p.y + this->GetSize().GetHeight() + 2));
menu->SetPosition(wxPoint(
menu->GetPosition().x - ((menu->GetSize().GetWidth() - this->GetSize().GetWidth()) / 2),
menu->GetPosition().y));
menu->Popup();
}
}
Let me know if I need to show more code.
This is probably a terrible way of doing this, but this is basically the first "serious" application I'm creating using the wxWidgets framework. Any help is appreciated.
when I choose an option from the menu, the main button's ID changes
(because when I reopen the menu the previously clicked button is light
up as its ID and the big button's ID match), but the label does not.
If you're creating the popup menu like in your previous post, you had a popup window with a panel as its child and the buttons were then children of the panel layed out with a sizer.
If that's still the case, this->GetParent() and should be the panel, this->GetParent()->GetParent() should be the popup. So this->GetParent()->GetParent()->GetParent() should be the trig function button (assuming you created the popup with the trig function button as the parent).
So I think the line wxWindow* mBtn = this->GetParent()->GetParent(); should be changed to wxWindow* mBtn = this->GetParent()->GetParent()->GetParent();.
Or slightly shorter wxWindow* mBtn = this->GetGrandParent()->GetParent();;
the popup is supposed to close itself when you left click on one of
the buttons, but it does not.
It looks like wxPopupTransientWindow has a special Dismiss method that is supposed to be used to close it.
So I think the line this->GetParent()->Close(true); should be changed to this->GetGrandParent()->Dismiss(); (Assuming as above that the buttons in the popup are children pf a panel).
Alternately, if you want a solution that will work regardless of the parentage of the controls in the popup window, you could have a utility function to find the popup ancestor which would look something like this:
wxPopupTransientWindow* FindPopup(wxWindow* w)
{
wxPopupTransientWindow* popup = NULL;
while ( w != NULL )
{
popup = wxDynamicCast(w, wxPopupTransientWindow);
if ( popup )
{
break;
}
w = w->GetParent();
}
return popup;
}
This uses the wxDynamicCast function which is slightly different from the c++ dynamic_cast expression. wxDynamicCast uses wxWidgets' RTTI system to check if the given pointer can be converted to the given type.
Then the mouseReleased method could use this utility function something like this:
void expandButton::mouseReleased(wxMouseEvent& evt)
{
if (pressed) {
pressed = false;
paintNow();
wxPopupTransientWindow* popup = FindPopup(this);
if (popup ) {
wxWindow* mBtn = popup->GetParent();
mBtn->SetLabel(this->GetLabel());
mBtn->SetId(this->GetId());
mBtn->Refresh();
popup->Dismiss();
}
}
}
I'm not sure why you're setting trig function button to have a new id, but I assume you have a reason.
To make the SetLabel method work in your custom button class, I think the easist thing is to call the SetLabel() method in the button's constructor. This will store the string passed to the constructor in the button's internal label member.
Based on other questions, I think the ikeButton constructor looks something like this:
ikeButton::ikeButton(wxFrame* parent, wxWindowID id, wxString text,...
{
...
this->text = text;
To store the label, you would need to change the line this->text = text; to
SetLabel(text);
And when you draw the button, I think the method you use looks like this:
void ikeButton::render(wxDC& dc)
{
...
dc.DrawText(text, ...);
}
You would need to change, the line dc.DrawText(text, ...); to
dc.DrawText(GetLabel(), ...);
Likewise, any other references to the button's text member should be changed to GetLabel() instead.
Finally, when you set the label in the expandButton::mouseReleased method, it might be a good idea to call button's Refresh() method to force the button to redraw itself. I added that my suggestion for the mouseReleased method above.

unhandled exception widget with sdkTrays in Ogre

I have some serious issues with sdkTrays in Ogre.
I have my OgreKinectGame that inherits from BaseApplication. BaseApplication is creating logo etc. using sdkTrayManager. I thought this mTrayMgr was inherited and can be used in my application as well.
I am trying to setup widgets for a HUD, but I'm getting unhandled exception errors.
My setupWidgets() function looks like this.
void OgreKinectGame::setupWidgets()
{
if(!mTrayMgr)
mTrayMgr = new SdkTrayManager("InterfaceName", mWindow, mMouse);
//mTrayMgr->destroyAllWidgets(); this caused exceptions as well
// create check boxes to toggle the visibility of our particle systems
const int WIDTH_UI = 160;
// main menu
mTrayMgr->createLabel(TL_CENTER, "mMainMenuLabel", "Main Menu", WIDTH_UI);
mTrayMgr->createButton(TL_CENTER, "mOptionButton", "Option");
mTrayMgr->createButton(TL_CENTER, "mCreditButton", "About");
mTrayMgr->createButton(TL_CENTER, "mQuitButton", "Quit");
mTrayMgr->showAll();
}
First, where did you initialize your setupWidgets()? , on BaseApplication class, they have setup(), you can create a virtual of this setup() to your main class and then initialize your setupWiget() there, e.g.,
bool OgreKinectGame::setup(void)
{
if (!BaseApplication::setup()) {
return false;
}
// Load fonts for tray captions
FontManager::getSingleton().getByName("SdkTrays/Caption")->load();
setupWidgets();//initialize here for your setupWidget()
}
second, I think your setupWidget() should be like this,
void OgreKinectGame::setupWidgets()
{
const int WIDTH_UI = 160;
// main menu
mTrayMgr->createLabel(TL_CENTER, "mMainMenuLabel", "Main Menu", WIDTH_UI);
mTrayMgr->createButton(TL_CENTER, "mOptionButton", "Option");
mTrayMgr->createButton(TL_CENTER, "mCreditButton", "About");
mTrayMgr->createButton(TL_CENTER, "mQuitButton", "Quit");
}
Can you try this solution and back again if still get crash?

The inferior stopped because it received signal from the Operating System error on resizable scrollarea

I have a QScrollArea inside QTabWidget and I have a QWidget beside my QTabWidget. I want QScrollArea to be resized when my main window is resized, so I have made this code like this:
void frmSummaryContact::on_btnAddNewContact_clicked()
{
MainWindow *mnWindow = qobject_cast<MainWindow *>(this->parent()->parent()->parent()->parent()->parent()->parent());
QTabWidget *tbWidget = qobject_cast<QTabWidget *>(this->parent()->parent()->parent()->parent());
frmDetailContact *frm = new frmDetailContact(mnWindow, "input", -1, mnWindow->rightPane());
QScrollArea *scrlForm = new QScrollArea;
scrlForm->setWidgetResizable(true);
scrlForm->setWidget(frm);
mnWindow->AddNewTab(tbWidget, scrlForm, "Add Contact");
}
my QTabWidget is in different form, so I cast it with qobject_cast. Meanwhile in another form, I have a toogle button to hide QWidget so my QTabWidget get wider. So in that form I have a code like this:
void frmDetailContactToggle::on_btnSearch_clicked()
{
MainWindow *mnWindow = qobject_cast<MainWindow *>(this->parent()->parent()->parent());
QLayoutItem *child;
while ((child = mnWindow->rightPane()->layout()->takeAt(0)) != 0)
child->widget()->setVisible(false);
mnWindow->rightPane()->setVisible(false);
QScrollArea *scrlContent = qobject_cast<QScrollArea *>(mnWindow->tabContentWidget()->currentWidget());
scrlContent->setWidgetResizable(false);
mnWindow->tabContentWidget()->setGeometry(mnWindow->tabContentWidget()->x(), mnWindow->tabContentWidget()->y(), m_width - mnWindow->tabContentWidget()->x() - 10, mnWindow->tabContentWidget()->height());
scrlContent->setWidgetResizable(true);
m_showRightPane = false;
}
I have realized that I can't change the geometry when WidgetResizable is true. It showed "The inferior stopped because it received signal from the Operating System" error. So I thought about making it false, changing the geometry, and making it true again. But when I want to make it true, I encounter the same error. Could anyone please help me to solve my problem?
if your program used uninitialized pointers,that may causes SIGSEGV.

How to change window title and central widget in Qt?

Hi, I have a problem with changing window title and central widget in Qt.
There is MainWindow:
class MainWindow : public QMainWindow
{
// (...)
QStackedWidget* widgets;
Quiz* widget1, *widget2;
}
and there is a class Quiz:
class Quiz : public QWidget
{
public slots:
void myClicked();
}
I wanted to change MainWindow title after clicking on button, which is a element of Quiz (and it is connected with slot myClicked).
void Quiz::myClicked()
{
static_cast<MainWindow>(parent).myFunction();
}
void MainWindow::myFunction()
{
widget2 = new Quiz(this,2);
widgets->addWidget(widget2);
std::cout<<"current wdgt: " << widgets->currentIndex() << std::endl; // shows: 0
widgets->setCurrentWidget(widget2);
std::cout<<"current wdgt " << widgets->currentIndex() << std::endl; // shows: 1
setWindowTitle("newTitle");
std::cout<<"Title is " << windowTitle().toStdString() << std::endl;
}
So widgets->currentIndex shows index of new widget but nothing is changed in my window. The same problem is with window title - method windowTitle() returns new title, but title on a titlebar is old. Why?
If I change title in Quiz::myClicked by:
parent->setWindowTitle("newTitle");
it works! Why it works how strange? Please help.
it works! Why it works how strange? Please help.
It is not strange. That is how the Qt API is designed. See the documentation for the explanation:
windowTitle : QString
This property holds the window title (caption).
This property only makes sense for top-level widgets, such as windows and dialogs.
Let us analyze the last sentence: your quiz is neither a QMainWindow, nor a QDialog, hence it cannot work. Windows titles only make sense for those based on the documentation. When you call it on the parent, it will work respectively since that is a QMainWindow.
The title bar shows the title of the MainWindow. Your Quiz widgets are "inside" the MainWindow, so their titles are not shown.
If you want to change the title bar text, you must call MainWindow::setWindowTitle().

My MFC Application Freezes if I Switch to Another App

Commence V 2.0 of this question.
My VC++ MFC application compiles and runs just fine. That is, until I switch to another window. As soon as my program loses focus, it freezes; I cannot switch back to it and if I move a window that is in front of it, my app window displays white in the space that the other window was covering.
Since I first posted this question I have been able to pinpoint what portion of my program is causing this behavior, but I still don't know what lines of code are wrong or why.
The main dialog of my MFC application contains a CTabCtrl called m_MainTabControl. This main tab control holds onto two tabs labeled "Basic Design" and "Advanced Design", each of which are tied to their own dialogs. Both dialogs contain a CTabCtrl with several tabs. And thus my problem is born.
When I first created this tab-within-tab structure, I was having problems with my program freezing up when I tried to switch between inner tabs. Needless to say I was puzzled by this, until I noticed that if I first clicked on a control on one of the inner tabs I could then switch tabs just fine. So without fully understanding what the problem was, I set the focus to the first inner tab of the first inner tab on program startup. Problem half solved. When I ran the program I could click around on the first set of inner tabs just fine; if I switched to the second outer tab and tried clicking around its inner tabs without first clicking on a dialog control, it would freeze again. So I made a Focus function to focus the currently selected inner tab of the currently selected outer tab and called that in my tab change event (the one that goes off when you click on another tab).
That is how I got to the point I was at when I first asked this question. I thought my program was working just fine, until I played around with it a bit more and noticed it wasn't playing nicely when I flipped back and forth between it and another window or program. More specifically, as soon as my program goes out of focus some process goes haywire and takes up an entire CPU's worth of processing.
And now, the reason I explained my little tab structure and focus problems in such great detail: after much experimentation, I found that if I commented out the second tab on my outer tab structure (i.e. the "Advanced Design" dialog and all of its little children tabs) the remaining bit of my program runs fine, and I can switch to another window and back without a fight. "Great," I thought, "that's only about 90% of my program that I just commented out to get this working. Let's try and pare it down further." I put the "Advanced Design" tabbed dialog back in, but commented out the tabbed dialogs created by the tab control within "Advanced Design" and everything still worked fine. One by one I put back the tabbed dialogs belonging to "Advanced Design"'s tab control and every time I reintroduced The Error regardless of what tab I uncommented. I should also point out that one of the first tabs I tried putting back in (alone, of course) was my "Margins" tab, which is a MarginDlg class that I ALSO USE UNDER MY "Basic Design" TAB WITHOUT TROUBLE. This leads me to believe that there is something specific I have to do when creating tabbed dialogs within tabbed dialogs that I am not doing, or am doing incorrectly, kind of like how I had to mess with focusing to make it work at first.
I would be EXTREMELY grateful for any light that can be shed on the situation. I am including what I think are relevant snippets of code; as always, let me know if more is needed.
variable declarations from main dialog's .h file:
//tab stuff
CTabCtrl m_MainTabControl;
vector<CDialog*> m_tabPages;
SimpDesDlg* simpDesDlg;
AdvDesDlg* advDesDlg;
When my application starts up, it creates my main dialog, and the OnInitDialog() is called:
(everything above the TODO: comment is default VS stuff dealing with the stupid about dialog)
BOOL CspAceDlg::OnInitDialog()
{
CDialog::OnInitDialog();
// Add "About..." menu item to system menu.
// IDM_ABOUTBOX must be in the system command range.
ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);
ASSERT(IDM_ABOUTBOX < 0xF000);
CMenu* pSysMenu = GetSystemMenu(FALSE);
if (pSysMenu != NULL)
{
CString strAboutMenu;
strAboutMenu.LoadString(IDS_ABOUTBOX);
if (!strAboutMenu.IsEmpty())
{
pSysMenu->AppendMenu(MF_SEPARATOR);
pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);
}
}
// Set the icon for this dialog. The framework does this automatically
// when the application's main window is not a dialog
SetIcon(m_hIcon, TRUE); // Set big icon
SetIcon(m_hIcon, FALSE); // Set small icon
// TODO: Add extra initialization here
///////////////////////////////////////
DrawResultsArea();
DrawTabs();
theApp.Calculate();
Focus();
//simpDesDlg->Focus();
//DrawToolbar();
return FALSE; // return TRUE unless you set the focus to a control
}
DrawTabs() is where I create the tabs for my outer tab control:
void CspAceDlg::DrawTabs()
{
simpDesDlg = new SimpDesDlg;
m_tabPages.push_back(simpDesDlg);
advDesDlg = new AdvDesDlg;
m_tabPages.push_back(advDesDlg);
// create a tcItem to hold the name of each tab during creation
// and then get inserted, and arrays holding the tab names and IDs of
// the dialogs they refer to
TC_ITEM tcItem;
PSTR pszTabNames[] = {"Basic Design", "Advanced Design"};
UINT pszTabItems[] = {IDD_SIMPLEDESIGNTAB, IDD_ADVANCEDDESIGNTAB};
//every member of m_tabPages[] will become a tab
for (int i = 0; i < int(m_tabPages.size()); i++)
{
//set up the tab name
tcItem.mask = TCIF_TEXT;
tcItem.pszText = pszTabNames[i];
tcItem.cchTextMax = int(strlen(pszTabNames[i]));
//insert the new tab into the tab control and create the dialog window
m_MainTabControl.InsertItem(i, &tcItem);
m_tabPages[i]->Create(pszTabItems[i], &m_MainTabControl);
}
//redraw so that the dialogs don't appear in upper left corner and cover the tabs
CRect tabRect, itemRect;
int nX, nY, nXc, nYc;
m_MainTabControl.GetClientRect(&tabRect);
m_MainTabControl.GetItemRect(0, &itemRect);
nX=itemRect.left;
nY=itemRect.bottom+1;
nXc=tabRect.right-itemRect.left-1;
nYc=tabRect.bottom-nY-1;
m_tabPages[0]->SetWindowPos(&wndTop, nX, nY, nXc, nYc, SWP_SHOWWINDOW);
for(int nCount=1; nCount < int(m_tabPages.size()); nCount++){
m_tabPages[nCount]->SetWindowPos(&wndTop, nX, nY, nXc, nYc, SWP_HIDEWINDOW);
}
}
Main dialog's Focus() method:
void CspAceDlg::Focus()
{
int curSel = m_MainTabControl.GetCurSel();
m_tabPages[curSel]->SetFocus();
//if it's the basic design, we need to focus its first tab
if (curSel == 0)
{
simpDesDlg->Focus();
}
//if it's the advanced design, we need to focus its first tab
else if (curSel == 1)
{
advDesDlg->Focus();
}
}
code for m_MainTabControl's tab selection change event:
void CspAceDlg::OnTcnSelchangeBuildtabs(NMHDR *pNMHDR, LRESULT *pResult)
{
for (int i = 0; i < int(m_tabPages.size()); i++)
{
m_tabPages[i]->ShowWindow(m_MainTabControl.GetCurSel() == i ? SW_SHOW :
SW_HIDE);
}
Focus();
*pResult = 0;
}
SimpDesDlg and AdvDesDlg's tabs use identical code except for tab initialization (just creating different tabs for each) so here's the code for AdvDesDlg:
OnInitDialog():
BOOL AdvDesDlg::OnInitDialog()
{
CDialog::OnInitDialog();
DrawTabs();
return false;
}
adding in the tabbed dialogs:
void AdvDesDlg::DrawTabs()
{
//Make the dialogs for the tabs
antennaDlg = new AntennaDlg;
commSEDlg = new CommSEDlg;
encryptorDlg = new EncryptorDlg;
marginDlg = new MarginDlg;
miscDlg = new MiscDlg;
transRecDlg = new TransRecDlg;
//add them all to the tabPages vector
m_tabPages.push_back(antennaDlg);
m_tabPages.push_back(commSEDlg);
m_tabPages.push_back(encryptorDlg);
m_tabPages.push_back(marginDlg);
m_tabPages.push_back(miscDlg);
m_tabPages.push_back(transRecDlg);
//m_tabPages[0] = new AntennaDlg;
//m_tabPages[1] = new CommSEDlg;
//m_tabPages[2] = new EncryptorDlg;
//m_tabPages[3] = new MarginDlg;
//m_tabPages[4] = new MiscDlg;
//m_tabPages[5] = new TransRecDlg;
//antennaDlg = (AntennaDlg*) m_tabPages[0];
//commSEDlg = (CommSEDlg*) m_tabPages[1];
//encryptorDlg = (EncryptorDlg*) m_tabPages[2];
//marginDlg = (MarginDlg*) m_tabPages[3];
//miscDlg = (MiscDlg*) m_tabPages[4];
//transRecDlg = (TransRecDlg*) m_tabPages[5];
// create a tcItem to hold the name of each tab during creation
// and then get inserted, and arrays holding the tab names and IDs of
// the dialogs they refer to
TC_ITEM tcItem;
PSTR pszTabNames[] = {"Antenna", "Comm Support", "Encryptor", "Margins", "Misc", "Trasmitter/Receiver"};
UINT pszTabItems[] = {IDD_ANTENNATAB, IDD_COMMSETAB, IDD_ENCRYPTORTAB, IDD_MARGINTAB, IDD_MISCTAB, IDD_TRANSRECTAB};
//every member of m_tabPages[] will become a tab
for (int i = 0; i < int(m_tabPages.size())/*(sizeof(m_tabPages)/sizeof(m_tabPages[0]))*/; i++)
{
//set up the tab name
tcItem.mask = TCIF_TEXT;
tcItem.pszText = pszTabNames[i];
tcItem.cchTextMax = int(strlen(pszTabNames[i]));
//insert the new tab into the tab control and create the dialog window
advTab.InsertItem(i, &tcItem);
m_tabPages[i]->Create(pszTabItems[i], &advTab);
}
//redraw so that the dialogs don't appear in upper left corner and cover the tabs
CRect tabRect, itemRect;
int nX, nY, nXc, nYc;
advTab.GetClientRect(&tabRect);
advTab.GetItemRect(0, &itemRect);
nX=itemRect.left;
nY=itemRect.bottom+1;
nXc=tabRect.right-itemRect.left-1;
nYc=tabRect.bottom-nY-1;
//m_tabPages[0]->SetWindowPos(&wndTop, nX, nY, nXc, nYc, SWP_SHOWWINDOW);
for(int nCount=/*1*/0; nCount < int(m_tabPages.size())/*(sizeof(m_tabPages)/sizeof(m_tabPages[0]))*/; nCount++){
m_tabPages[nCount]->SetWindowPos(&wndTop, nX, nY, nXc, nYc, SWP_HIDEWINDOW);
}
}
And the Focus() and tab changing:
void AdvDesDlg::Focus()
{
this->SetFocus();
for (int i = 0; i < int(m_tabPages.size())/*(sizeof(m_tabPages)/sizeof(m_tabPages[0]))*/; i++)
{
m_tabPages[i]->ShowWindow(advTab.GetCurSel() == i ? SW_SHOW :
SW_HIDE);
}
int curSel = advTab.GetCurSel();
m_tabPages[curSel]->SetFocus();
}
void AdvDesDlg::OnTcnSelchangeAdvDesign(NMHDR *pNMHDR, LRESULT *pResult)
{
for (int i = 0; i < int(m_tabPages.size())/*(sizeof(m_tabPages)/sizeof(m_tabPages[0]))*/; i++)
{
m_tabPages[i]->ShowWindow(advTab.GetCurSel() == i ? SW_SHOW :
SW_HIDE);
}
int curSel = advTab.GetCurSel();
m_tabPages[curSel]->SetFocus();
*pResult = 0;
}
Debug your app, get it into this state, then go Debug / Break All. Find the main thread in the Threads window, then look at the call stack. Somewhere in the call stack will be your code that's causing the hang.
Note that in order to get a sensible call stack you'll need to point Visual Studio at Microsoft's symbol servers; see http://msdn.microsoft.com/en-us/library/b8ttk8zy.aspx
The behavior you describe usually occurs when you are running some process without allowing the message pump to run.
What does your app do? I assume you start it, and then either hit a button or select a menu item to start some process.
If the program behaves normally when you first start it (before you click to start your processing), but then behaves as you describe after starting the process, then that's your problem.
You'll have to move that processing into another thread to allow the MFC GUI to remain responsive.
I just stumbled about a very similar situation. My setup:
A CPropertySheet containing several CPropertyPages
A CTabCtrl inside one CPropertyPage
Several CDialogs as part of the CTabCtrl
Using a control in one specific CDialog and then switching to another application (e.g. Visual Studio via a hit breakpoint) will stall my application (the respective CPU core ends up at 100% load)
Using a control in the same specific CDialog but then switching to another CPropertyPage before switching to another application will not result in any problems
After some research I found this Knowledge Base article which hinted me to a solution. The specific CDialog which triggered the stall had the line EXSTYLE WS_EX_CONTROLPARENT in its resource definition. Removing the line solved the problem.
This prevents being able to tab into the CDialog, but that problem is slightly less serious and I might come back to it another day.
I had a similar issue. I had multiple nested windows, some with the WS_EX_CONTROLPARENT style, some not. The thing is: Either all inner windows have to have this style, or none of them (at least apparently).