examples: use QSignalBlocker

Examples should show idiomatic Qt, and QSignalBlocker is idiomatic
since it's inception in Qt 5.3. Just updating the examples was
forgotten.

This commit makes good for that.

Fix coding-style issues as a drive-by.

Change-Id: If138e87ea2ab7a444599734113f7cc6df11fb42d
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

1 files changed, 17 insertions, 14 deletions

diff --git a/examples/widgets/mainwindows/mainwindow/colorswatch.cpp b/examples/widgets/mainwindows/mainwindow/colorswatch.cpp
index d746bbe8d3..efc94f7d97 100644
--- a/examples/widgets/mainwindows/mainwindow/colorswatch.cpp
+++ b/examples/widgets/mainwindows/mainwindow/colorswatch.cpp
@@ -44,6 +44,7 @@
 #include <QDialog>
 #include <QDialogButtonBox>
 #include <QGridLayout>
+#include <QSignalBlocker>
 #include <QSpinBox>
 #include <QLabel>
 #include <QPainterPath>
@@ -409,20 +410,22 @@ void ColorSwatch::updateContextMenu()
         allowBottomAction->setEnabled(area != Qt::BottomDockWidgetArea);
     }
 
-    leftAction->blockSignals(true);
-    rightAction->blockSignals(true);
-    topAction->blockSignals(true);
-    bottomAction->blockSignals(true);
-
-    leftAction->setChecked(area == Qt::LeftDockWidgetArea);
-    rightAction->setChecked(area == Qt::RightDockWidgetArea);
-    topAction->setChecked(area == Qt::TopDockWidgetArea);
-    bottomAction->setChecked(area == Qt::BottomDockWidgetArea);
-
-    leftAction->blockSignals(false);
-    rightAction->blockSignals(false);
-    topAction->blockSignals(false);
-    bottomAction->blockSignals(false);
+    {
+        const QSignalBlocker blocker(leftAction);
+        leftAction->setChecked(area == Qt::LeftDockWidgetArea);
+    }
+    {
+        const QSignalBlocker blocker(rightAction);
+        rightAction->setChecked(area == Qt::RightDockWidgetArea);
+    }
+    {
+        const QSignalBlocker blocker(topAction);
+        topAction->setChecked(area == Qt::TopDockWidgetArea);
+    }
+    {
+        const QSignalBlocker blocker(bottomAction);
+        bottomAction->setChecked(area == Qt::BottomDockWidgetArea);
+    }
 
     if (areaActions->isEnabled()) {
         leftAction->setEnabled(areas & Qt::LeftDockWidgetArea);