[processing] Constrain model item resizing to prevent items being res…

…ized to a too small size
qgis · Mar 18, 2020 · 7614de4 · 7614de4
1 parent d64cafe
commit 7614de4
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Showing 7 changed files with 37 additions and 12 deletions.
diff --git a/python/gui/auto_generated/processing/models/qgsmodelcomponentgraphicitem.sip.in b/python/gui/auto_generated/processing/models/qgsmodelcomponentgraphicitem.sip.in
@@ -108,7 +108,7 @@ Shows a preview of moving the item from its stored position by ``dx``, ``dy``.
 Sets a new scene ``rect`` for the item.
 %End
 
-    void previewItemRectChange( QRectF rect );
+    QRectF previewItemRectChange( QRectF rect );
 %Docstring
 Shows a preview of setting a new ``rect`` for the item.
 %End

diff --git a/src/gui/processing/models/qgsmodelcomponentgraphicitem.cpp b/src/gui/processing/models/qgsmodelcomponentgraphicitem.cpp
@@ -146,15 +146,24 @@ void QgsModelComponentGraphicItem::setItemRect( QRectF )
   emit updateArrowPaths();
 }
 
-void QgsModelComponentGraphicItem::previewItemRectChange( QRectF rect )
+QRectF QgsModelComponentGraphicItem::previewItemRectChange( QRectF rect )
 {
   rect = rect.normalized();
+
+  if ( rect.width() < MIN_COMPONENT_WIDTH )
+    rect.setWidth( MIN_COMPONENT_WIDTH );
+  if ( rect.height() < MIN_COMPONENT_HEIGHT )
+    rect.setHeight( MIN_COMPONENT_HEIGHT );
+
   setPos( rect.center() );
   prepareGeometryChange();
+
   mTempSize = rect.size();
 
   updateButtonPositions();
   emit updateArrowPaths();
+
+  return rect;
 }
 
 void QgsModelComponentGraphicItem::modelHoverEnterEvent( QgsModelViewMouseEvent *event )

diff --git a/src/gui/processing/models/qgsmodelcomponentgraphicitem.h b/src/gui/processing/models/qgsmodelcomponentgraphicitem.h
@@ -133,7 +133,7 @@ class GUI_EXPORT QgsModelComponentGraphicItem : public QGraphicsObject
     /**
      * Shows a preview of setting a new \a rect for the item.
      */
-    void previewItemRectChange( QRectF rect );
+    QRectF previewItemRectChange( QRectF rect );
 
 #ifndef SIP_RUN
 
@@ -358,6 +358,9 @@ class GUI_EXPORT QgsModelComponentGraphicItem : public QGraphicsObject
     QgsModelDesignerFlatButtonGraphicItem *mEditButton = nullptr;
     QgsModelDesignerFlatButtonGraphicItem *mDeleteButton = nullptr;
 
+    static constexpr double MIN_COMPONENT_WIDTH = 70;
+    static constexpr double MIN_COMPONENT_HEIGHT = 50;
+
     static constexpr double DEFAULT_BUTTON_WIDTH = 16;
     static constexpr double DEFAULT_BUTTON_HEIGHT = 16;
     static constexpr double BUTTON_MARGIN = 2;

diff --git a/src/gui/processing/models/qgsmodelviewmousehandles.cpp b/src/gui/processing/models/qgsmodelviewmousehandles.cpp
@@ -141,12 +141,13 @@ void QgsModelViewMouseHandles::setItemRect( QGraphicsItem *item, QRectF rect )
   }
 }
 
-void QgsModelViewMouseHandles::previewSetItemRect( QGraphicsItem *item, QRectF rect )
+QRectF QgsModelViewMouseHandles::previewSetItemRect( QGraphicsItem *item, QRectF rect )
 {
   if ( QgsModelComponentGraphicItem *componentItem = dynamic_cast<QgsModelComponentGraphicItem *>( item ) )
   {
-    componentItem->previewItemRectChange( rect );
+    return componentItem->previewItemRectChange( rect );
   }
+  return rect;
 }
 
 void QgsModelViewMouseHandles::startMacroCommand( const QString &text )

diff --git a/src/gui/processing/models/qgsmodelviewmousehandles.h b/src/gui/processing/models/qgsmodelviewmousehandles.h
@@ -62,7 +62,7 @@ class GUI_EXPORT QgsModelViewMouseHandles: public QgsGraphicsViewMouseHandles
     void moveItem( QGraphicsItem *item, double deltaX, double deltaY ) override;
     void previewItemMove( QGraphicsItem *item, double deltaX, double deltaY ) override;
     void setItemRect( QGraphicsItem *item, QRectF rect ) override;
-    void previewSetItemRect( QGraphicsItem *item, QRectF rect ) override;
+    QRectF previewSetItemRect( QGraphicsItem *item, QRectF rect ) override;
     void startMacroCommand( const QString &text ) override;
     void endMacroCommand() override;
 

diff --git a/src/gui/qgsgraphicsviewmousehandles.cpp b/src/gui/qgsgraphicsviewmousehandles.cpp
@@ -65,9 +65,9 @@ void QgsGraphicsViewMouseHandles::previewItemMove( QGraphicsItem *, double, doub
 
 }
 
-void QgsGraphicsViewMouseHandles::previewSetItemRect( QGraphicsItem *, QRectF )
+QRectF QgsGraphicsViewMouseHandles::previewSetItemRect( QGraphicsItem *, QRectF )
 {
-
+  return QRectF();
 }
 
 void QgsGraphicsViewMouseHandles::startMacroCommand( const QString & )
@@ -1025,19 +1025,21 @@ void QgsGraphicsViewMouseHandles::resizeMouseMove( QPointF currentPosition, bool
     mResizeRect = QRectF( QPointF( -( mBeginHandleWidth + rx ), -( mBeginHandleHeight + ry ) ), QPointF( 0, 0 ) );
   }
 
-  setRect( 0, 0, std::fabs( mBeginHandleWidth + rx ), std::fabs( mBeginHandleHeight + ry ) );
-
   const QList<QGraphicsItem *> selectedItems = selectedSceneItems( false );
+  QRectF newHandleBounds;
   for ( QGraphicsItem *item : selectedItems )
   {
     //get stored item bounds in mouse handle item's coordinate system
     QRectF thisItemRect = mapRectFromScene( storedItemRect( item ) );
     //now, resize it relative to the current resized dimensions of the mouse handles
     relativeResizeRect( thisItemRect, QRectF( -mResizeMoveX, -mResizeMoveY, mBeginHandleWidth, mBeginHandleHeight ), mResizeRect );
 
-    previewSetItemRect( item, mapRectToScene( thisItemRect ) );
+    thisItemRect = mapRectFromScene( previewSetItemRect( item, mapRectToScene( thisItemRect ) ) );
+    newHandleBounds = newHandleBounds.isValid() ? newHandleBounds.united( thisItemRect ) : thisItemRect;
   }
 
+  setRect( newHandleBounds.isValid() ? newHandleBounds : QRectF( 0, 0, std::fabs( mBeginHandleWidth + rx ), std::fabs( mBeginHandleHeight + ry ) ) );
+
   //show current size of selection in status bar
   showStatusMessage( tr( "width: %1 mm height: %2 mm" ).arg( rect().width() ).arg( rect().height() ) );
 

diff --git a/src/gui/qgsgraphicsviewmousehandles.h b/src/gui/qgsgraphicsviewmousehandles.h
@@ -120,7 +120,17 @@ class GUI_EXPORT QgsGraphicsViewMouseHandles: public QObject, public QGraphicsRe
     virtual void moveItem( QGraphicsItem *item, double deltaX, double deltaY ) = 0;
     virtual void previewItemMove( QGraphicsItem *item, double deltaX, double deltaY );
     virtual void setItemRect( QGraphicsItem *item, QRectF rect ) = 0;
-    virtual void previewSetItemRect( QGraphicsItem *item, QRectF rect );
+
+    /**
+     * Called when a resize or move action is in progress and the effects can be previewed for the specified \a item. The
+     * \a rect argument gives the new "transient" rectangular bounds of \a item (in item coordinates).
+     *
+     * If implemented, the method should return the item's calculated desired rect given the specified \a rect. This allows
+     * an item to override the rect results, e.g. by applying a minimum size constraint. The returned value
+     * should be in the item's coordinates.
+     */
+    virtual QRectF previewSetItemRect( QGraphicsItem *item, QRectF rect );
+
     virtual void startMacroCommand( const QString &text );
     virtual void endMacroCommand();
     virtual void createItemCommand( QGraphicsItem *item );