Clicking on a panel doesn't restore focus to correct child in wxGTK

[shaurz]

The current implementation wxWindowGTK::SetFocus() calls gtk_widget_child_focus(widget, GTK_DIR_TAB_FORWARD). Unfortunately this causes the *next* child widget (in tab order) of the container to be focused if a child widget had already been previously focused. The fix is to focus GtkContainer::focus_child if has been set.

Fix attached.

[vadz]

So do I understand correctly that calling SetFocus() on the container when the focus is on one of its children moves the focus to the next child? If so, why do we need to call gtk_widget_grab_focus() at all, couldn't we just do nothing in this case?

[shaurz]

For example, if you have a panel with 2 controls on it. Click on one of the controls, then focus another panel, then click on the original panel. It should focus the control that was previously focused, but instead it focuses the second control that was never clicked. The focus_child member is how GTK remember which child to refocus in a container (since a container itself never gets focus unless it has no child controls).

We discovered this problem with the HyperTreeList control with checkboxes. Every time you clicked the tree control it would cycle through the checkboxes.

[vadz]

I don't think the problem is in this function at all, in particular modifying it as suggested doesn't fix it for me. The real problem is that when using "generic" (i.e. implemented by wx itself) focus handling, we remember last focused child in each of the panels. But when using native support for it, we don't do this at all, see src/common/containr.cpp. And so every time you set focus to a panel, it's set to its first child. Which is exactly what I see with this simple example:

samples/minimal/minimal.cpp

@@ -172 +172 @@
     CreateStatusBar(2);
     SetStatusText("Welcome to wxWidgets!");
 #endif // wxUSE_STATUSBAR
+
+    wxSizer* sizer = new wxBoxSizer(wxHORIZONTAL);
+
+    wxPanel* p1 = new wxPanel(this);
+    wxSizer* sizer1 = new wxBoxSizer(wxVERTICAL);
+    sizer1->Add(new wxButton(p1, wxID_OK), wxSizerFlags().Border());
+    sizer1->Add(new wxButton(p1, wxID_CANCEL), wxSizerFlags().Border());
+    p1->SetSizer(sizer1);
+    sizer->Add(p1);
+
+    wxPanel* p2 = new wxPanel(this);
+    wxSizer* sizer2 = new wxBoxSizer(wxVERTICAL);
+    sizer2->Add(new wxButton(p2, wxID_OPEN), wxSizerFlags().Border());
+    sizer2->Add(new wxButton(p2, wxID_SAVE), wxSizerFlags().Border());
+    p2->SetSizer(sizer2);
+    sizer->Add(p2);
+
+    SetSizerAndFit(sizer);
 }
 
 

To be honest I don't really see how could this work at all... The only possibility I see is to not do anything at all when the panel is clicked in wxGTK but this hardly seems ideal neither.

Any other/better ideas?