Dynamically set number of columns to show in character widget

based on widget width, and avoid unnecessary horizontal scroll bar

python/gui/auto_generated/symbology/characterwidget.sip.in

@@ -128,6 +128,8 @@ Emitted when a character is selected in the widget.
 
     virtual void paintEvent( QPaintEvent *event );
 
+    virtual void resizeEvent( QResizeEvent *event );
+
 
 };
 

src/gui/qgsscrollarea.cpp

@@ -16,6 +16,7 @@
 #include <QEvent>
 #include <QMouseEvent>
 #include "qgsscrollarea.h"
+#include <QScrollBar>
 
 // milliseconds to swallow child wheel events for after a scroll occurs
 #define TIMEOUT 1000

src/gui/symbology/characterwidget.cpp

@@ -256,3 +256,9 @@ void CharacterWidget::paintEvent( QPaintEvent *event )
     }
   }
 }
+
+void CharacterWidget::resizeEvent( QResizeEvent *event )
+{
+  mColumns = event->size().width() / mSquareSize;
+  QWidget::resizeEvent( event );
+}

src/gui/symbology/characterwidget.h

@@ -161,6 +161,7 @@ class GUI_EXPORT CharacterWidget : public QWidget
     void mouseMoveEvent( QMouseEvent *event ) override;
     void mousePressEvent( QMouseEvent *event ) override;
     void paintEvent( QPaintEvent *event ) override;
+    void resizeEvent( QResizeEvent *event ) override;
 
   private:
     QFont mDisplayFont;

src/gui/symbology/qgssymbollayerwidget.cpp

@@ -3253,6 +3253,7 @@ QgsFontMarkerSymbolLayerWidget::QgsFontMarkerSymbolLayerWidget( QgsVectorLayer *
 
   widgetChar = new CharacterWidget();
   scrollArea->setWidget( widgetChar );
+  scrollArea->setVerticalOnly( true );
 
   btnColor->setAllowOpacity( true );
   btnColor->setColorDialogTitle( tr( "Select Symbol Fill Color" ) );

src/ui/symbollayer/widget_fontmarker.ui

@@ -360,7 +360,7 @@
        </property>
        <property name="sizeHint" stdset="0">
         <size>
-         <width>20</width>
+         <width>0</width>
          <height>40</height>
         </size>
        </property>