use nullptr consistently (clang-tidy)

From now on we prefer nullptr instead of 0 to clarify cases where
we are assigning or testing a pointer rather than a numeric zero.

Also, replaced cases where 0 was passed as Qt::KeyboardModifiers
with Qt::NoModifier (clang-tidy replaced them with nullptr, which
waas wrong, so it was just as well to make the tests more readable
rather than to revert those lines).

Change-Id: I4735d35e4d9f42db5216862ce091429eadc6e65d
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

3 files changed, 3 insertions, 3 deletions

diff --git a/examples/qml/tutorials/extending-qml/chapter4-customPropertyTypes/piechart.cpp b/examples/qml/tutorials/extending-qml/chapter4-customPropertyTypes/piechart.cpp
index 0107a1fc69..066963cf33 100644
--- a/examples/qml/tutorials/extending-qml/chapter4-customPropertyTypes/piechart.cpp
+++ b/examples/qml/tutorials/extending-qml/chapter4-customPropertyTypes/piechart.cpp
@@ -51,7 +51,7 @@
 #include "pieslice.h"
 
 PieChart::PieChart(QQuickItem *parent)
-    : QQuickItem(parent), m_pieSlice(0)
+    : QQuickItem(parent), m_pieSlice(nullptr)
 {
 }
 
diff --git a/examples/qml/tutorials/extending-qml/chapter5-listproperties/piechart.cpp b/examples/qml/tutorials/extending-qml/chapter5-listproperties/piechart.cpp
index 699fce14ca..ac680bb9c9 100644
--- a/examples/qml/tutorials/extending-qml/chapter5-listproperties/piechart.cpp
+++ b/examples/qml/tutorials/extending-qml/chapter5-listproperties/piechart.cpp
@@ -68,7 +68,7 @@ void PieChart::setName(const QString &name)
 //![0]
 QQmlListProperty<PieSlice> PieChart::slices()
 {
-    return QQmlListProperty<PieSlice>(this, 0, &PieChart::append_slice, 0, 0, 0);
+    return QQmlListProperty<PieSlice>(this, nullptr, &PieChart::append_slice, nullptr, nullptr, nullptr);
 }
 
 void PieChart::append_slice(QQmlListProperty<PieSlice> *list, PieSlice *slice)
diff --git a/examples/qml/tutorials/extending-qml/chapter6-plugins/import/piechart.cpp b/examples/qml/tutorials/extending-qml/chapter6-plugins/import/piechart.cpp
index 40b31b32de..1c712c887a 100644
--- a/examples/qml/tutorials/extending-qml/chapter6-plugins/import/piechart.cpp
+++ b/examples/qml/tutorials/extending-qml/chapter6-plugins/import/piechart.cpp
@@ -67,7 +67,7 @@ void PieChart::setName(const QString &name)
 
 QQmlListProperty<PieSlice> PieChart::slices()
 {
-    return QQmlListProperty<PieSlice>(this, 0, &PieChart::append_slice, 0, 0, 0);
+    return QQmlListProperty<PieSlice>(this, nullptr, &PieChart::append_slice, nullptr, nullptr, nullptr);
 }
 
 void PieChart::append_slice(QQmlListProperty<PieSlice> *list, PieSlice *slice)