Merge branch 'qt-radio-groups'

Fix radio button grouping in Qt.

See https://github.com/wxWidgets/wxWidgets/pull/1212

include/wx/qt/radiobut.h

@@ -37,8 +37,6 @@ public:
 
     virtual QWidget *GetHandle() const;
 
-protected:
-
 private:
     QRadioButton *m_qtRadioButton;
 

src/qt/radiobut.cpp

@@ -13,6 +13,53 @@
 #include "wx/qt/private/winevent.h"
 
 #include <QtWidgets/QRadioButton>
+#include <QtWidgets/QButtonGroup>
+
+namespace
+{
+
+// Tiny helper applying a safe cast to return the handle of wxRadioButton as
+// its actual type.
+inline
+QRadioButton* QtGetRadioButton(wxRadioButton* radioBtn)
+{
+    return static_cast<QRadioButton*>(radioBtn->GetHandle());
+}
+
+void QtStartNewGroup(QRadioButton* qtRadioButton)
+{
+    // Note that the QButtonGroup created here will be deallocated when its
+    // parent // QRadioButton is destroyed.
+    QButtonGroup* qtButtonGroup = new QButtonGroup(qtRadioButton);
+    qtButtonGroup->addButton(qtRadioButton);
+}
+
+bool QtTryJoiningExistingGroup(wxRadioButton* radioBtnThis)
+{
+    for ( wxWindow* previous = radioBtnThis->GetPrevSibling();
+          previous;
+          previous = previous->GetPrevSibling() )
+    {
+        if ( wxRadioButton* radioBtn = wxDynamicCast(previous, wxRadioButton) )
+        {
+            // We should never join the exclusive group of wxRB_SINGLE button.
+            if ( !radioBtn->HasFlag(wxRB_SINGLE) )
+            {
+                if ( QButtonGroup *qtGroup = QtGetRadioButton(radioBtn)->group() )
+                {
+                    qtGroup->addButton(QtGetRadioButton(radioBtnThis));
+                    return true;
+                }
+            }
+
+            break;
+        }
+    }
+
+    return false;
+}
+
+} // anonymous namespace
 
 class wxQtRadioButton : public wxQtEventSignalHandler< QRadioButton, wxRadioButton >
 {
@@ -65,7 +112,27 @@ bool wxRadioButton::Create( wxWindow *parent,
     m_qtRadioButton = new wxQtRadioButton( parent, this );
     m_qtRadioButton->setText( wxQtConvertString( label ));
 
-    return QtCreateControl( parent, id, pos, size, style, validator, name );
+    if ( !QtCreateControl(parent, id, pos, size, style, validator, name) )
+        return false;
+
+    // Check if we need to create a new button group: this must be done when
+    // explicitly requested to do so (wxRB_GROUP) but also for wxRB_SINGLE
+    // buttons to prevent them implicitly becoming part of an existing group.
+    if ( (style & wxRB_GROUP) || (style & wxRB_SINGLE) )
+    {
+        QtStartNewGroup(m_qtRadioButton);
+    }
+    else
+    {
+        // Otherwise try to join an already existing group. Currently we don't
+        // do anything if joining it fails, i.e. if there is no current group
+        // yet, because the radio buttons not explicitly associated with some
+        // group still work as if they were part of one, so we just ignore the
+        // return value of this function.
+        QtTryJoiningExistingGroup(this);
+    }
+
+    return true;
 }
 
 void wxRadioButton::SetValue(bool value)

tests/controls/radiobuttontest.cpp

@@ -17,6 +17,7 @@
 #ifndef WX_PRECOMP
     #include "wx/app.h"
     #include "wx/radiobut.h"
+    #include "wx/stattext.h"
 #endif // WX_PRECOMP
 
 #include "wx/uiaction.h"
@@ -105,22 +106,25 @@ void RadioButtonTestCase::Value()
 
 void RadioButtonTestCase::Group()
 {
-    //Add another button to the first group and create another of two buttons
-    wxRadioButton* g1radio0 = new wxRadioButton(wxTheApp->GetTopWindow(),
-                                                wxID_ANY, "wxRadioButton",
-                                                wxDefaultPosition,
-                                                wxDefaultSize, wxRB_GROUP);
+    wxWindow* const parent = wxTheApp->GetTopWindow();
 
-    wxRadioButton* g1radio1 = new wxRadioButton(wxTheApp->GetTopWindow(),
-                                                wxID_ANY, "wxRadioButton");
+    // Create two different radio groups.
+    wxRadioButton* g1radio0 = new wxRadioButton(parent, wxID_ANY, "radio 1.0",
+                                                wxDefaultPosition, wxDefaultSize,
+                                                wxRB_GROUP);
 
-    wxRadioButton* g2radio0 = new wxRadioButton(wxTheApp->GetTopWindow(),
-                                                wxID_ANY, "wxRadioButton",
-                                                wxDefaultPosition,
-                                                wxDefaultSize, wxRB_GROUP);
+    wxRadioButton* g1radio1 = new wxRadioButton(parent, wxID_ANY, "radio 1.1");
 
-    wxRadioButton* g2radio1 = new wxRadioButton(wxTheApp->GetTopWindow(),
-                                                wxID_ANY, "wxRadioButton");
+    wxRadioButton* g2radio0 = new wxRadioButton(parent, wxID_ANY, "radio 2.0",
+                                                wxDefaultPosition, wxDefaultSize,
+                                                wxRB_GROUP);
+
+    wxRadioButton* g2radio1 = new wxRadioButton(parent, wxID_ANY, "radio 2.1");
+
+    // Check that having another control between radio buttons doesn't break
+    // grouping.
+    wxStaticText* text = new wxStaticText(parent, wxID_ANY, "Label");
+    wxRadioButton* g2radio2 = new wxRadioButton(parent, wxID_ANY, "radio 2.1");
 
     g1radio0->SetValue(true);
     g2radio0->SetValue(true);
@@ -138,6 +142,11 @@ void RadioButtonTestCase::Group()
     CPPUNIT_ASSERT(!g2radio0->GetValue());
     CPPUNIT_ASSERT(g2radio1->GetValue());
 
+    g2radio2->SetValue(true);
+    CPPUNIT_ASSERT(!g2radio0->GetValue());
+    CPPUNIT_ASSERT(!g2radio1->GetValue());
+    CPPUNIT_ASSERT(g2radio2->GetValue());
+
     g1radio0->SetValue(true);
     g2radio0->SetValue(true);
 
@@ -150,6 +159,8 @@ void RadioButtonTestCase::Group()
     wxDELETE(g1radio1);
     wxDELETE(g2radio0);
     wxDELETE(g2radio1);
+    wxDELETE(g2radio2);
+    wxDELETE(text);
 }
 
 void RadioButtonTestCase::Single()