Adjust horizontal gap between icons in grid view to equal distribute

icons over space.
Issue #1169

widgets/listview.cpp

@@ -40,6 +40,7 @@ ListView::ListView(QWidget *parent)
     , eventFilter(nullptr)
     , menu(nullptr)
     , zoomLevel(1.0)
+    , prevWidth(0)
 {
     setDragEnabled(true);
     setContextMenuPolicy(Qt::NoContextMenu);
@@ -140,6 +141,15 @@ void ListView::paintEvent(QPaintEvent *e)
     QListView::paintEvent(e);
 }
 
+void ListView::resizeEvent(QResizeEvent *e)
+{
+    QListView::resizeEvent(e);
+    if (IconMode==viewMode() && width()!=prevWidth) {
+        emit widthChanged();
+        prevWidth=width();
+    }
+}
+
 // Workaround for https://bugreports.qt-project.org/browse/QTBUG-18009
 void ListView::correctSelection()
 {