Move more functionality to c++ base class

python/gui/auto_generated/processing/models/qgsmodelcomponentgraphicitem.sip.in

@@ -47,6 +47,20 @@ Returns the model component associated with this item.
     QgsProcessingModelAlgorithm *model();
 %Docstring
 Returns the model associated with this item.
+%End
+
+    QFont font() const;
+%Docstring
+Returns the font used to render text in the item.
+
+.. seealso:: :py:func:`setFont`
+%End
+
+    void setFont( const QFont &font );
+%Docstring
+Sets the ``font`` used to render text in the item.
+
+.. seealso:: :py:func:`font`
 %End
 
   signals:
@@ -78,6 +92,14 @@ The default implementation does nothing.
 Called when the component should be deleted.
 
 The default implementation does nothing.
+%End
+
+  protected:
+
+    QString truncatedTextForItem( const QString &text ) const;
+%Docstring
+Truncates a ``text`` string so that it fits nicely within the item's width,
+accounting for margins and interactive buttons.
 %End
 
 };

python/plugins/processing/modeler/ModelerGraphicItem.py

@@ -48,21 +48,17 @@ pluginPath = os.path.split(os.path.dirname(__file__))[0]
 
 class ModelerGraphicItem(QgsModelComponentGraphicItem):
 
-    BUTTON_WIDTH = 16
-
     repaintArrows = pyqtSignal()
     updateArrowPaths = pyqtSignal()
 
     def __init__(self, element, model):
         super().__init__(element, model, None)
-        self.item_font = QFont()
-        self.item_font.setPixelSize(12)
         self.pixmap = None
         self.picture = None
         self.hover_over_item = False
 
     def boundingRect(self):
-        fm = QFontMetricsF(self.item_font)
+        fm = QFontMetricsF(self.font())
         unfolded = isinstance(self.component(),
                               QgsProcessingModelChildAlgorithm) and not self.component().parametersCollapsed()
         numParams = len([a for a in self.component().algorithm().parameterDefinitions() if
@@ -107,19 +103,6 @@ class ModelerGraphicItem(QgsModelComponentGraphicItem):
             self.update()
             self.repaintArrows.emit()
 
-    def getAdjustedText(self, text):
-        fm = QFontMetricsF(self.item_font)
-        w = fm.width(text)
-        if w < self.component().size().width() - 25 - ModelerGraphicItem.BUTTON_WIDTH:
-            return text
-
-        text = text[0:-3] + '…'
-        w = fm.width(text)
-        while w > self.component().size().width() - 25 - ModelerGraphicItem.BUTTON_WIDTH:
-            text = text[0:-4] + '…'
-            w = fm.width(text)
-        return text
-
     def itemRect(self):
         return QRectF(-(self.component().size().width() + 2) / 2.0,
                       -(self.component().size().height() + 2) / 2.0,
@@ -149,14 +132,14 @@ class ModelerGraphicItem(QgsModelComponentGraphicItem):
         painter.setPen(QPen(stroke, 0))  # 0 width "cosmetic" pen
         painter.setBrush(QBrush(color, Qt.SolidPattern))
         painter.drawRect(rect)
-        painter.setFont(self.item_font)
+        painter.setFont(self.font())
         painter.setPen(QPen(Qt.black))
-        text = self.getAdjustedText(self.text)
+        text = self.truncatedTextForItem(self.text)
         if isinstance(self.component(), QgsProcessingModelChildAlgorithm) and not self.component().isActive():
             painter.setPen(QPen(Qt.gray))
             text = text + "\n(deactivated)"
-        fm = QFontMetricsF(self.item_font)
-        text = self.getAdjustedText(self.text)
+        fm = QFontMetricsF(self.font())
+        text = self.truncatedTextForItem(self.text)
         h = fm.ascent()
         pt = QPointF(-self.component().size().width() / 2 + 25, self.component().size().height() / 2.0 - h + 1)
         painter.drawText(pt, text)
@@ -170,7 +153,7 @@ class ModelerGraphicItem(QgsModelComponentGraphicItem):
             if not self.component().parametersCollapsed():
                 for param in [p for p in self.component().algorithm().parameterDefinitions() if not p.isDestination()]:
                     if not param.flags() & QgsProcessingParameterDefinition.FlagHidden:
-                        text = self.getAdjustedText(param.description())
+                        text = self.truncatedTextForItem(param.description())
                         h = -(fm.height() * 1.2) * (i + 1)
                         h = h - self.component().size().height() / 2.0 + 5
                         pt = QPointF(-self.component().size().width() / 2 + 33, h)
@@ -182,7 +165,7 @@ class ModelerGraphicItem(QgsModelComponentGraphicItem):
             painter.drawText(pt, 'Out')
             if not self.component().outputsCollapsed():
                 for i, out in enumerate(self.component().algorithm().outputDefinitions()):
-                    text = self.getAdjustedText(out.description())
+                    text = self.truncatedTextForItem(out.description())
                     h = fm.height() * 1.2 * (i + 2)
                     h = h + self.component().size().height() / 2.0
                     pt = QPointF(-self.component().size().width() / 2 + 33, h)
@@ -202,7 +185,7 @@ class ModelerGraphicItem(QgsModelComponentGraphicItem):
         if isinstance(self.component(), QgsProcessingModelParameter):
             paramIndex = -1
             offsetX = 0
-        fm = QFontMetricsF(self.item_font)
+        fm = QFontMetricsF(self.font())
         if isinstance(self.component(), QgsProcessingModelChildAlgorithm):
             h = -(fm.height() * 1.2) * (paramIndex + 2) - fm.height() / 2.0 + 8
             h = h - self.component().size().height() / 2.0
@@ -214,8 +197,8 @@ class ModelerGraphicItem(QgsModelComponentGraphicItem):
         if isinstance(self.component(),
                       QgsProcessingModelChildAlgorithm) and self.component().algorithm().outputDefinitions():
             outputIndex = (outputIndex if not self.component().outputsCollapsed() else -1)
-            text = self.getAdjustedText(self.component().algorithm().outputDefinitions()[outputIndex].description())
-            fm = QFontMetricsF(self.item_font)
+            text = self.truncatedTextForItem(self.component().algorithm().outputDefinitions()[outputIndex].description())
+            fm = QFontMetricsF(self.font())
             w = fm.width(text)
             h = fm.height() * 1.2 * (outputIndex + 1) + fm.height() / 2.0
             y = h + self.component().size().height() / 2.0 + 5

src/gui/processing/models/qgsmodelcomponentgraphicitem.cpp

@@ -38,6 +38,8 @@ QgsModelComponentGraphicItem::QgsModelComponentGraphicItem( QgsProcessingModelCo
   setFlag( QGraphicsItem::ItemSendsGeometryChanges, true );
   setZValue( QgsModelGraphicsScene::ZValues::ModelComponent );
 
+  mFont.setPixelSize( 12 );
+
   QSvgRenderer svg( QgsApplication::iconPath( QStringLiteral( "mActionEditModelComponent.svg" ) ) );
   QPicture editPicture;
   QPainter painter( &editPicture );
@@ -69,6 +71,36 @@ QgsProcessingModelAlgorithm *QgsModelComponentGraphicItem::model()
   return mModel;
 }
 
+QFont QgsModelComponentGraphicItem::font() const
+{
+  return mFont;
+}
+
+void QgsModelComponentGraphicItem::setFont( const QFont &font )
+{
+  mFont = font;
+  update();
+}
+
+QString QgsModelComponentGraphicItem::truncatedTextForItem( const QString &text ) const
+{
+  QFontMetricsF fm( mFont );
+  double width = fm.boundingRect( text ).width();
+  if ( width < mComponent->size().width() - 25 - mButtonSize.width() )
+    return text;
+
+  QString t = text;
+  t = t.left( t.length() - 3 ) + QChar( 0x2026 );
+  width = fm.boundingRect( t ).width();
+  while ( width > mComponent->size().width() - 25 - mButtonSize.width() )
+  {
+    t = t.left( t.length() - 4 ) + QChar( 0x2026 );
+    width = fm.boundingRect( t ).width();
+  }
+  return t;
+}
+
+
 QgsModelParameterGraphicItem::QgsModelParameterGraphicItem( QgsProcessingModelParameter *parameter, QgsProcessingModelAlgorithm *model, QGraphicsItem *parent )
   : QgsModelComponentGraphicItem( parameter, model, parent )
 {

src/gui/processing/models/qgsmodelcomponentgraphicitem.h

@@ -19,6 +19,7 @@
 #include "qgis.h"
 #include "qgis_gui.h"
 #include <QGraphicsObject>
+#include <QFont>
 
 class QgsProcessingModelComponent;
 class QgsProcessingModelParameter;
@@ -63,6 +64,18 @@ class GUI_EXPORT QgsModelComponentGraphicItem : public QGraphicsObject
      */
     QgsProcessingModelAlgorithm *model();
 
+    /**
+     * Returns the font used to render text in the item.
+     * \see setFont()
+     */
+    QFont font() const;
+
+    /**
+     * Sets the \a font used to render text in the item.
+     * \see font()
+     */
+    void setFont( const QFont &font );
+
   signals:
 
     // TEMPORARY ONLY during refactoring
@@ -96,6 +109,14 @@ class GUI_EXPORT QgsModelComponentGraphicItem : public QGraphicsObject
      */
     virtual void deleteComponent() {}
 
+  protected:
+
+    /**
+     * Truncates a \a text string so that it fits nicely within the item's width,
+     * accounting for margins and interactive buttons.
+     */
+    QString truncatedTextForItem( const QString &text ) const;
+
   private:
 
     std::unique_ptr< QgsProcessingModelComponent > mComponent;
@@ -108,6 +129,8 @@ class GUI_EXPORT QgsModelComponentGraphicItem : public QGraphicsObject
     static constexpr double DEFAULT_BUTTON_HEIGHT = 16;
     QSizeF mButtonSize { DEFAULT_BUTTON_WIDTH, DEFAULT_BUTTON_HEIGHT };
 
+    QFont mFont;
+
 };
 
 /**