[plasmalnf] Prevent duplicate widgets

- Only create widgets for themes once
 - Update visible texts as needed

src/modules/plasmalnf/PlasmaLnfPage.cpp

@@ -30,6 +30,7 @@ ThemeInfo::ThemeInfo( const KPluginMetaData& data )
     : id( data.pluginId() )
     , name( data.name() )
     , description( data.description() )
+    , widget( nullptr )
 {
 }
 
@@ -136,18 +137,27 @@ void PlasmaLnfPage::fillUi()
         return;
     }
 
-    if ( m_buttonGroup )
-        delete m_buttonGroup;
-    m_buttonGroup = new QButtonGroup( this );
-    m_buttonGroup->setExclusive( true );
+    if ( !m_buttonGroup )
+    {
+        m_buttonGroup = new QButtonGroup( this );
+        m_buttonGroup->setExclusive( true );
+    }
 
     int c = 1; // After the general explanation
     for ( auto& theme : m_enabledThemes )
     {
-        ThemeWidget* w = new ThemeWidget( theme );
-        m_buttonGroup->addButton( w->button() );
-        ui->verticalLayout->insertWidget( c, w );
-        connect( w, &ThemeWidget::themeSelected, this, &PlasmaLnfPage::plasmaThemeSelected);
+        if ( !theme.widget )
+        {
+            ThemeWidget* w = new ThemeWidget( theme );
+            m_buttonGroup->addButton( w->button() );
+            ui->verticalLayout->insertWidget( c, w );
+            connect( w, &ThemeWidget::themeSelected, this, &PlasmaLnfPage::plasmaThemeSelected);
+            theme.widget = w;
+        }
+        else
+        {
+            theme.widget->updateThemeName( theme );
+        }
         ++c;
     }
 }

src/modules/plasmalnf/ThemeInfo.h

@@ -23,6 +23,7 @@
 #include <QString>
 
 class KPluginMetaData;
+class ThemeWidget;
 
 /** @brief describes a single plasma LnF theme.
  *
@@ -37,18 +38,22 @@ struct ThemeInfo
     QString name;
     QString description;
     QString imagePath;
+    ThemeWidget* widget;
 
     ThemeInfo()
+        : widget( nullptr )
     {}
 
     explicit ThemeInfo( const QString& _id )
         : id( _id )
+        , widget( nullptr )
     {
     }
 
     explicit ThemeInfo( const QString& _id, const QString& image )
         : id( _id )
         , imagePath( image )
+        , widget( nullptr )
     {}
 
     // Defined in PlasmaLnfPage.cpp

src/modules/plasmalnf/ThemeWidget.cpp

@@ -29,6 +29,7 @@
 ThemeWidget::ThemeWidget(const ThemeInfo& info, QWidget* parent)
     : QWidget( parent )
     , m_check( new QRadioButton( info.name.isEmpty() ? info.id : info.name, parent ) )
+    , m_description( new QLabel( info.description, parent ) )
     , m_id( info.id )
 {
     QHBoxLayout* layout = new QHBoxLayout( this );
@@ -44,7 +45,7 @@ ThemeWidget::ThemeWidget(const ThemeInfo& info, QWidget* parent)
         // Not found or not specified, so convert the name into some (horrible, likely)
         // color instead.
         image = QPixmap( image_size );
-        uint hash_color = qHash( info.imagePath );
+        uint hash_color = qHash( info.imagePath.isEmpty() ? info.id : info.imagePath );
         cDebug() << "Theme image" << info.imagePath << "not found, hash" << hash_color;
         image.fill( QColor( QRgb( hash_color ) ) );
     }
@@ -54,7 +55,7 @@ ThemeWidget::ThemeWidget(const ThemeInfo& info, QWidget* parent)
     QLabel* image_label = new QLabel( this );
     image_label->setPixmap( image );
     layout->addWidget( image_label, 1 );
-    layout->addWidget( new QLabel( info.description, this ), 3 );
+    layout->addWidget( m_description, 3 );
 
     connect( m_check, &QRadioButton::clicked, this, &ThemeWidget::clicked );
 }
@@ -71,3 +72,9 @@ ThemeWidget::button() const
 {
     return m_check;
 }
+
+void ThemeWidget::updateThemeName(const ThemeInfo& info)
+{
+    m_check->setText( info.name );
+    m_description->setText( info.description );
+}

src/modules/plasmalnf/ThemeWidget.h

@@ -22,6 +22,7 @@
 #include <QWidget>
 
 class QAbstractButton;
+class QLabel;
 class QRadioButton;
 
 struct ThemeInfo;
@@ -34,6 +35,8 @@ public:
 
     QAbstractButton* button() const;
 
+    void updateThemeName( const ThemeInfo& info );
+
 signals:
     void themeSelected( const QString& id );
 
@@ -43,6 +46,7 @@ public slots:
 private:
     QString m_id;
     QRadioButton* m_check;
+    QLabel* m_description;
 } ;
 
 #endif