[partition] Introduce post-reset slot for boot loader selection

src/modules/partition/gui/PartitionPage.cpp

@@ -79,6 +79,7 @@ PartitionPage::PartitionPage( PartitionCoreModule* core, QWidget* parent )
                     value( "alwaysShowPartitionLabels" ).toBool() );
     m_ui->deviceComboBox->setModel( m_core->deviceModel() );
     m_ui->bootLoaderComboBox->setModel( m_core->bootLoaderModel() );
+    connect( m_core->bootLoaderModel(), &QAbstractItemModel::modelReset, this, &PartitionPage::restoreSelectedBootLoader );
     PartitionBarsView::NestedPartitionsMode mode = Calamares::JobQueue::instance()->globalStorage()->
                                                    value( "drawNestedPartitions" ).toBool() ?
                                                        PartitionBarsView::DrawNestedPartitions :
@@ -505,6 +506,12 @@ PartitionPage::updateSelectedBootLoaderIndex()
     cDebug() << "Selected bootloader index" << m_lastSelectedBootLoaderIndex;
 }
 
+void
+PartitionPage::restoreSelectedBootLoader()
+{
+}
+
+
 void
 PartitionPage::updateFromCurrentDevice()
 {

src/modules/partition/gui/PartitionPage.h

@@ -57,6 +57,8 @@ private slots:
     void updateBootLoaderInstallPath();
     /// @brief Explicitly selected boot loader path
     void updateSelectedBootLoaderIndex();
+    /// @brief After boot loader model changes, try to preserve previously set value
+    void restoreSelectedBootLoader();
 
 private:
     QScopedPointer< Ui_PartitionPage > m_ui;