Allow columns with percentage width

src/blackgui/models/columns.cpp

@@ -185,6 +185,58 @@ namespace BlackGui
             return column >= 0 && column < m_columns.size();
         }
 
+        bool CColumns::hasAnyWidthPercentage() const
+        {
+            for (const CColumn &c : m_columns) { if (c.hasWidthPercentage()) { return true; }}
+            return false;
+        }
+
+        void CColumns::setWidthPercentages(const QList<int> percentages)
+        {
+            if (percentages.isEmpty())
+            {
+                for (CColumn &column : m_columns) { column.setWidthPercentage(-1); }
+                return;
+            }
+
+            int c = 0;
+            for (CColumn &column : m_columns)
+            {
+                column.setWidthPercentage(percentages.at(c++));
+            }
+        }
+
+        QList<int> CColumns::calculateWidths(int totalWidth) const
+        {
+            if (m_columns.isEmpty() || !this->hasAnyWidthPercentage()) { return {}; }
+
+            int totalPercentage = 0;
+            const int averagePercentage = 100 / m_columns.size();
+
+            for (const CColumn &c : m_columns)
+            {
+                totalPercentage += c.hasWidthPercentage() ? c.getWidthPercentage() : averagePercentage;
+            }
+
+            if (totalPercentage < 1) { return {}; }
+
+            // ideally totalPercentage would be 100%, but there is no guarantee
+            const double part = static_cast<double>(totalWidth) / totalPercentage;
+            QList<int> widths;
+
+            int usedWidth = 0;
+            for (const CColumn &c : m_columns)
+            {
+                const int percentage = c.hasWidthPercentage() ? c.getWidthPercentage() : averagePercentage;
+                const int restWidth = totalWidth - usedWidth;
+                const int width = qMin(restWidth, qRound(part * percentage));
+                widths.push_back(width);
+                usedWidth += width;
+            }
+
+            return widths;
+        }
+
         const CDefaultFormatter *CColumns::getFormatter(const QModelIndex &index) const
         {
             if (!isValidColumn(index)) { return nullptr; }

src/blackgui/models/columns.h

@@ -92,6 +92,15 @@ namespace BlackGui
             //! Translation context
             void setTranslationContext(const QString &translationContext) { m_translationContext = translationContext; }
 
+            //! Width in percentage
+            int getWidthPercentage() const { return m_widthPercentage; }
+
+            //! Having a width percentage
+            bool hasWidthPercentage() const { return m_widthPercentage > 0; }
+
+            //! Width percentage
+            void setWidthPercentage(int width) { m_widthPercentage = width; }
+
             //! Get a standard value object formatted column
             static CColumn standardValueObject(const QString &headerName, const BlackMisc::CPropertyIndex &propertyIndex, int alignment = CDefaultFormatter::alignDefault());
 
@@ -114,6 +123,7 @@ namespace BlackGui
             QString m_translationContext;
             QString m_columnName;
             QString m_columnToolTip;
+            int m_widthPercentage = -1;
             QSharedPointer<CDefaultFormatter> m_formatter; //!< Used formatter
             BlackMisc::CPropertyIndex m_propertyIndex;     //!< Property index for column
             BlackMisc::CPropertyIndex m_sortPropertyIndex; //!< Property index used when sorted (optional alternative)
@@ -202,6 +212,15 @@ namespace BlackGui
             //! Columns
             const QList<CColumn> &columns() const { return m_columns; }
 
+            //! Any column with width percentage?
+            bool hasAnyWidthPercentage() const;
+
+            //! Set the width percentages
+            void setWidthPercentages(const QList<int> percentages);
+
+            //! Calculate the absolute width
+            QList<int> calculateWidths(int totalWidth) const;
+
         private:
             QList<CColumn> m_columns;
             QString m_translationContext; //!< for future usage