fix (with unknown but apparently beneficial effects) for TAB navigation in radio buttons (patch 1038330)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@32214 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/containr.cpp

@@ -153,6 +153,111 @@ void wxControlContainer::SetLastFocus(wxWindow *win)
     }
 }
 
+// --------------------------------------------------------------------
+// The following four functions are used to find other radio buttons 
+// within the same group. Used by wxSetFocusToChild on wxMSW
+// --------------------------------------------------------------------
+
+#ifdef __WXMSW__
+
+wxRadioButton* wxGetPreviousButtonInGroup(wxRadioButton *btn)
+{
+    if ( btn->HasFlag(wxRB_GROUP) || btn->HasFlag(wxRB_SINGLE) )
+        return NULL;
+
+    const wxWindowList& siblings = btn->GetParent()->GetChildren();
+    wxWindowList::compatibility_iterator nodeThis = siblings.Find(btn);
+    wxCHECK_MSG( nodeThis, NULL, _T("radio button not a child of its parent?") );
+
+    // Iterate over all previous siblings until we find the next radio button
+    wxWindowList::compatibility_iterator nodeBefore = nodeThis->GetPrevious();
+    wxRadioButton *prevBtn = 0;
+    while (nodeBefore)
+    {
+        prevBtn = wxDynamicCast(nodeBefore->GetData(), wxRadioButton);
+        if (prevBtn)
+            break;
+
+        nodeBefore = nodeBefore->GetPrevious();
+    }
+    
+    if (!prevBtn || prevBtn->HasFlag(wxRB_SINGLE))
+    {
+        // no more buttons in group
+        return NULL;
+    }
+    else
+        return prevBtn;
+}
+
+wxRadioButton* wxGetNextButtonInGroup(wxRadioButton *btn)
+{
+    if (btn->HasFlag(wxRB_SINGLE))
+        return NULL;
+
+    const wxWindowList& siblings = btn->GetParent()->GetChildren();
+    wxWindowList::compatibility_iterator nodeThis = siblings.Find(btn);
+    wxCHECK_MSG( nodeThis, NULL, _T("radio button not a child of its parent?") );
+
+    // Iterate over all previous siblings until we find the next radio button
+    wxWindowList::compatibility_iterator nodeNext = nodeThis->GetNext();
+    wxRadioButton *nextBtn = 0;
+    while (nodeNext)
+    {
+        nextBtn = wxDynamicCast(nodeNext->GetData(), wxRadioButton);
+        if (nextBtn)
+            break;
+
+        nodeNext = nodeNext->GetNext();
+    }
+
+    if ( !nextBtn || nextBtn->HasFlag(wxRB_GROUP) || nextBtn->HasFlag(wxRB_SINGLE) )
+    {
+        // no more buttons or the first button of the next group
+        return NULL;
+    }
+    else
+        return nextBtn;
+}
+
+wxRadioButton* wxGetFirstButtonInGroup(wxRadioButton *btn)
+{
+    while (true)
+    {
+        wxRadioButton* prevBtn = wxGetPreviousButtonInGroup(btn);
+        if (!prevBtn)
+            return btn;
+        
+        btn = prevBtn;
+    }
+}
+
+wxRadioButton* wxGetSelectedButtonInGroup(wxRadioButton *btn)
+{
+    // Find currently selected button
+    if (btn->GetValue())
+        return btn;
+
+    if (btn->HasFlag(wxRB_SINGLE))
+        return NULL;
+
+    wxRadioButton *selBtn;
+
+    // First check all previous buttons
+    for (selBtn = wxGetPreviousButtonInGroup(btn); selBtn; selBtn = wxGetPreviousButtonInGroup(selBtn))
+        if (selBtn->GetValue())
+            return selBtn;
+
+    // Now all following buttons
+    for (selBtn = wxGetNextButtonInGroup(btn); selBtn; selBtn = wxGetNextButtonInGroup(selBtn))
+        if (selBtn->GetValue())
+            return selBtn;
+
+    return NULL;
+}
+
+#endif __WXMSW__
+
 // ----------------------------------------------------------------------------
 // Keyboard handling - this is the place where the TAB traversal logic is
 // implemented. As this code is common to all ports, this ensures consistent
@@ -224,6 +329,12 @@ void wxControlContainer::HandleOnNavigationKey( wxNavigationKeyEvent& event )
 
         if ( winFocus )
         {
+#ifdef __WXMSW__
+            // If we are in a radio button group, start from the first item in the 
+            // group
+            if ( event.IsFromTab() && wxIsKindOf(winFocus, wxRadioButton ) )
+                winFocus = wxGetFirstButtonInGroup((wxRadioButton*)winFocus);
+#endif
             // ok, we found the focus - now is it our child?
             start_node = children.Find( winFocus );
         }
@@ -291,14 +402,40 @@ void wxControlContainer::HandleOnNavigationKey( wxNavigationKeyEvent& event )
 
         wxWindow *child = node->GetData();
 
-#if defined(__WXMSW__)
-        bool is_not_msw_rb = !m_winLastFocused ||
-                                !wxIsKindOf(m_winLastFocused,wxRadioButton);
+#ifdef __WXMSW__
+        bool canSelectRadioButton = true;
+        if (!event.IsFromTab())
+        {
+            // If navigating using cursor keys, make sure not to navigate out of a radio button group.
+            if (m_winLastFocused && wxIsKindOf(m_winLastFocused, wxRadioButton))
+            {
+                if (!wxIsKindOf(child, wxRadioButton))
+                {
+                    child = forward ? 
+                                wxGetNextButtonInGroup((wxRadioButton*)m_winLastFocused) : 
+                                wxGetPreviousButtonInGroup((wxRadioButton*)m_winLastFocused);
+                    if (!child)
+                    {
+                        event.Skip(false);
+                        return;
+                    }
+                }
+            }
+        }
+        else
+        {
+            // If navigating using tabs, skip all but the first radio button in a group.
+            if (wxIsKindOf(child, wxRadioButton))
+            {
+                if (wxGetPreviousButtonInGroup((wxRadioButton*)child))
+                    canSelectRadioButton = false;
+            }
+        }
 #else
-        static const bool is_not_msw_rb = true;
+        static bool canSelectRadioButton = true;
 #endif
 
-        if ( child->AcceptsFocusFromKeyboard() && is_not_msw_rb )
+        if ( child->AcceptsFocusFromKeyboard() && canSelectRadioButton )
         {
             // if we're setting the focus to a child panel we should prevent it
             // from giving it to the child which had the focus the last time
@@ -310,28 +447,11 @@ void wxControlContainer::HandleOnNavigationKey( wxNavigationKeyEvent& event )
             // we need to hop to the next activated
             // radio button, not just the next radio
             // button under MSW
-            if (wxIsKindOf(child,wxRadioButton))
+            if (wxIsKindOf(child, wxRadioButton) && event.IsFromTab())
             {
-                wxRadioButton *rb = (wxRadioButton*) child;
-                if (!rb->GetValue())
-                {
-                    for (;;)
-                    {
-                        wxWindowList::compatibility_iterator node = children.Find( child );
-                        if (forward)
-                            node = node->GetNext();
-                        else
-                            node = node->GetPrevious();
-                        if (!node)
-                            return; // this would probably an error
-                        child = node->GetData();
-                        if (!wxIsKindOf(child,wxRadioButton))
-                            continue;
-                        rb = (wxRadioButton*) child;
-                        if (rb->GetValue())
-                            break;
-                    }
-                }
+                wxRadioButton *rb = wxGetSelectedButtonInGroup((wxRadioButton*)child);
+                if (rb)
+                    child = rb;
             }
 #endif // __WXMSW__
 
@@ -475,6 +595,18 @@ bool wxSetFocusToChild(wxWindow *win, wxWindow **childLastFocused)
 
         if ( child->AcceptsFocusFromKeyboard() && !child->IsTopLevel() )
         {
+#ifdef __WXMSW__
+            // If a radiobutton is the first focusable child, search for the 
+            // selected radiobutton in the same group
+            wxRadioButton* btn = wxDynamicCast(child, wxRadioButton);
+            if (btn)
+            {
+                wxRadioButton* selected = wxGetSelectedButtonInGroup(btn);
+                if (selected)
+                    child = selected;
+            }
+#endif
+
             wxLogTrace(_T("focus"),
                        _T("SetFocusToChild() => first child (0x%08lx)."),
                        (unsigned long)child->GetHandle());