+ // ::IsDialogMessage() is broken and may sometimes hang the
+ // application by going into an infinite loop, so we try to detect
+ // [some of] the situatations when this may happen and not call it
+ // then
+
+ // assume we can call it by default
+ bool canSafelyCallIsDlgMsg = TRUE;
+
+ HWND hwndFocus = ::GetFocus();
+
+ // if the currently focused window itself has WS_EX_CONTROLPARENT style, ::IsDialogMessage() will also enter
+ // an infinite loop, because it will recursively check the child
+ // windows but not the window itself and so if none of the children
+ // accepts focus it loops forever (as it only stops when it gets
+ // back to the window it started from)
+ //
+ // while it is very unusual that a window with WS_EX_CONTROLPARENT
+ // style has the focus, it can happen. One such possibility is if
+ // all windows are either toplevel, wxDialog, wxPanel or static
+ // controls and no window can actually accept keyboard input.
+#if !defined(__WXWINCE__)
+ if ( ::GetWindowLong(hwndFocus, GWL_EXSTYLE) & WS_EX_CONTROLPARENT )
+ {
+ // passimistic by default
+ canSafelyCallIsDlgMsg = FALSE;
+ for ( wxWindowList::compatibility_iterator node = GetChildren().GetFirst();
+ node;
+ node = node->GetNext() )
+ {
+ wxWindow * const win = node->GetData();
+ if ( win->AcceptsFocus() &&
+ !(::GetWindowLong(GetHwndOf(win), GWL_EXSTYLE) &
+ WS_EX_CONTROLPARENT) )
+ {
+ // it shouldn't hang...
+ canSafelyCallIsDlgMsg = TRUE;
+
+ break;
+ }
+ }
+ }
+#endif // !__WXWINCE__
+
+ if ( canSafelyCallIsDlgMsg )
+ {
+ // ::IsDialogMessage() can enter in an infinite loop when the
+ // currently focused window is disabled or hidden and its
+ // parent has WS_EX_CONTROLPARENT style, so don't call it in
+ // this case
+ while ( hwndFocus )
+ {
+ if ( !::IsWindowEnabled(hwndFocus) ||
+ !::IsWindowVisible(hwndFocus) )
+ {
+ // it would enter an infinite loop if we do this!
+ canSafelyCallIsDlgMsg = FALSE;
+
+ break;
+ }
+
+ if ( !(::GetWindowLong(hwndFocus, GWL_STYLE) & WS_CHILD) )
+ {
+ // it's a top level window, don't go further -- e.g. even
+ // if the parent of a dialog is disabled, this doesn't
+ // break navigation inside the dialog
+ break;
+ }
+
+ hwndFocus = ::GetParent(hwndFocus);
+ }
+ }
+
+ // let IsDialogMessage() have the message if it's safe to call it
+ if ( canSafelyCallIsDlgMsg && ::IsDialogMessage(GetHwnd(), msg) )
+ {
+ // IsDialogMessage() did something...
+ return TRUE;
+ }
+ }
projects / wxWidgets.git / blobdiff