tdf#130857 qt weld: Evaluate radio button groups

Add support for radio button groups by implementing
QtBuilder::setRadioButtonGroup.

Qt provides QButtonGroup [1] to explicitly group
buttons. Quoting from the QRadioButton doc [2]:

> Radio buttons are autoExclusive by default. If auto-exclusive is
> enabled, radio buttons that belong to the same parent widget behave as
> if they were part of the same exclusive button group. If you need
> multiple exclusive button groups for radio buttons that belong to the
> same parent widget, put them into a QButtonGroup.

To make sure exactly one button group exists and it gets
freed automatically, make the radio button whose ID is set for
the GtkRadioButton::group property [3] the parent (and thus the
owner) of the group.
Set a pointer of the group as a property for that button,
so it can be retrieved directly from the button without requiring
another map/... to keep track.

With this in place, the radio buttons in Writer's
"Tools" -> "Options" -> "LibreOfficeDev Writer"
-> "Mail Merge Email" -> "Server Authentication"
dialog are now grouped into 2 groups as expected in
a WIP branch, rather than all of them being in one group (because
they all have the same grid as a parent).
Support for that dialog will be declared in an
upcoming commit.

[1] https://doc.qt.io/qt-6/qbuttongroup.html
[2] https://doc.qt.io/qt-6/qradiobutton.html
[3] https://docs.gtk.org/gtk3/property.RadioButton.group.html

Change-Id: I60e8b5b525411c299ac50a8712361cc8572cc403
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/178444
Tested-by: Jenkins
Reviewed-by: Michael Weghorn <m.weghorn@posteo.de>

1 files changed, 25 insertions, 2 deletions

diff --git a/vcl/qt5/QtBuilder.cxx b/vcl/qt5/QtBuilder.cxx
index 963d8e71e861..7d78acb281f8 100644
--- a/vcl/qt5/QtBuilder.cxx
+++ b/vcl/qt5/QtBuilder.cxx
@@ -20,6 +20,7 @@
 #include <vcl/qt/QtUtils.hxx>
 
 #include <QtGui/QStandardItemModel>
+#include <QtWidgets/QButtonGroup>
 #include <QtWidgets/QCheckBox>
 #include <QtWidgets/QComboBox>
 #include <QtWidgets/QDialog>
@@ -275,6 +276,7 @@ QObject* QtBuilder::makeObject(QObject* pParent, std::u16string_view sName, std:
     else if (sName == u"GtkRadioButton")
     {
         pObject = new QRadioButton(pParentWidget);
+        extractRadioButtonGroup(sID, rMap);
     }
     else if (sName == u"GtkScrolledWindow")
     {
@@ -473,9 +475,30 @@ void QtBuilder::setMnemonicWidget(const OUString& rLabelId, const OUString& rMne
     pLabel->setBuddy(static_cast<QWidget*>(pBuddy));
 }
 
-void QtBuilder::setRadioButtonGroup(const OUString&, const OUString&)
+void QtBuilder::setRadioButtonGroup(const OUString& rRadioButtonId, const OUString& rRadioGroupId)
 {
-    SAL_WARN("vcl.qt", "Not implemented yet");
+    // insert all buttons into a button group owned by button whose matches the group's
+    QRadioButton* pGroupOwner = get<QRadioButton>(rRadioGroupId);
+    assert(pGroupOwner && "No radio button with the given group name");
+
+    QButtonGroup* pButtonGroup = nullptr;
+    static const char* const pPropertyKey = "PROPERTY_BUTTONGROUP";
+    QVariant aVariant = pGroupOwner->property(pPropertyKey);
+    if (aVariant.canConvert<QButtonGroup*>())
+    {
+        pButtonGroup = aVariant.value<QButtonGroup*>();
+    }
+    else
+    {
+        pButtonGroup = new QButtonGroup(pGroupOwner);
+        pButtonGroup->addButton(pGroupOwner);
+    }
+
+    QRadioButton* pRadioButton = get<QRadioButton>(rRadioButtonId);
+    assert(pRadioButton && "No radio button with given ID");
+    pButtonGroup->addButton(pRadioButton);
+
+    pGroupOwner->setProperty(pPropertyKey, QVariant::fromValue(pButtonGroup));
 }
 
 void QtBuilder::setPriority(QObject*, int) { SAL_WARN("vcl.qt", "Ignoring priority"); }