Examples: Add equality an operator to Extending Qml Advanced tutorials

This allows for more meaningful checks for identical assignment in
Person::setShoe().

Amends: 405bd42998

Change-Id: Id731f3f9163fb311ff9b04e2bbf4786a3022a11b
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
(cherry picked from commit 8fab8cf39c)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

examples/qml/tutorials/extending-qml-advanced/advanced4-Grouped-properties/person.cpp

@@ -60,6 +60,12 @@ void ShoeDescription::setPrice(qreal price)
     }
 }
 
+bool ShoeDescription::operatorEqualsImpl(const ShoeDescription &lhs, const ShoeDescription &rhs)
+{
+    return lhs.m_size == rhs.m_size && lhs.m_color == rhs.m_color && lhs.m_brand == rhs.m_brand
+            && lhs.m_price == rhs.m_price;
+}
+
 QString Person::name() const
 {
     return m_name;
@@ -80,7 +86,10 @@ ShoeDescription *Person::shoe() const
 
 void Person::setShoe(ShoeDescription *shoe)
 {
-    if (m_shoe != shoe) {
+    if (!shoe)
+        return;
+
+    if (*m_shoe != *shoe) {
         m_shoe = shoe;
         emit shoeChanged();
     }

examples/qml/tutorials/extending-qml-advanced/advanced4-Grouped-properties/person.h

@@ -31,10 +31,21 @@ public:
     qreal price() const;
     void setPrice(qreal);
 
+    friend bool operator==(const ShoeDescription &lhs, const ShoeDescription &rhs)
+    {
+        return operatorEqualsImpl(lhs, rhs);
+    }
+    friend bool operator!=(const ShoeDescription &lhs, const ShoeDescription &rhs)
+    {
+        return !operatorEqualsImpl(lhs, rhs);
+    }
+
 signals:
     void shoeChanged();
 
 private:
+    static bool operatorEqualsImpl(const ShoeDescription &, const ShoeDescription &);
+
     int m_size = 0;
     QColor m_color;
     QString m_brand;

examples/qml/tutorials/extending-qml-advanced/advanced5-Attached-properties/person.cpp

@@ -60,6 +60,12 @@ void ShoeDescription::setPrice(qreal price)
     }
 }
 
+bool ShoeDescription::operatorEqualsImpl(const ShoeDescription &lhs, const ShoeDescription &rhs)
+{
+    return lhs.m_size == rhs.m_size && lhs.m_color == rhs.m_color && lhs.m_brand == rhs.m_brand
+            && lhs.m_price == rhs.m_price;
+}
+
 QString Person::name() const
 {
     return m_name;
@@ -80,7 +86,10 @@ ShoeDescription *Person::shoe() const
 
 void Person::setShoe(ShoeDescription *shoe)
 {
-    if (m_shoe != shoe) {
+    if (!shoe)
+        return;
+
+    if (*m_shoe != *shoe) {
         m_shoe = shoe;
         emit shoeChanged();
     }

examples/qml/tutorials/extending-qml-advanced/advanced5-Attached-properties/person.h

@@ -31,10 +31,21 @@ public:
     qreal price() const;
     void setPrice(qreal);
 
+    friend bool operator==(const ShoeDescription &lhs, const ShoeDescription &rhs)
+    {
+        return operatorEqualsImpl(lhs, rhs);
+    }
+    friend bool operator!=(const ShoeDescription &lhs, const ShoeDescription &rhs)
+    {
+        return !operatorEqualsImpl(lhs, rhs);
+    }
+
 signals:
     void shoeChanged();
 
 private:
+    static bool operatorEqualsImpl(const ShoeDescription &, const ShoeDescription &);
+
     int m_size = 0;
     QColor m_color;
     QString m_brand;

examples/qml/tutorials/extending-qml-advanced/advanced6-Property-value-source/person.cpp

@@ -60,6 +60,12 @@ void ShoeDescription::setPrice(qreal price)
     }
 }
 
+bool ShoeDescription::operatorEqualsImpl(const ShoeDescription &lhs, const ShoeDescription &rhs)
+{
+    return lhs.m_size == rhs.m_size && lhs.m_color == rhs.m_color && lhs.m_brand == rhs.m_brand
+            && lhs.m_price == rhs.m_price;
+}
+
 QString Person::name() const
 {
     return m_name;
@@ -80,7 +86,10 @@ ShoeDescription *Person::shoe() const
 
 void Person::setShoe(ShoeDescription *shoe)
 {
-    if (m_shoe != shoe) {
+    if (!shoe)
+        return;
+
+    if (*m_shoe != *shoe) {
         m_shoe = shoe;
         emit shoeChanged();
     }

examples/qml/tutorials/extending-qml-advanced/advanced6-Property-value-source/person.h

@@ -31,10 +31,21 @@ public:
     qreal price() const;
     void setPrice(qreal);
 
+    friend bool operator==(const ShoeDescription &lhs, const ShoeDescription &rhs)
+    {
+        return operatorEqualsImpl(lhs, rhs);
+    }
+    friend bool operator!=(const ShoeDescription &lhs, const ShoeDescription &rhs)
+    {
+        return !operatorEqualsImpl(lhs, rhs);
+    }
+
 signals:
     void shoeChanged();
 
 private:
+    static bool operatorEqualsImpl(const ShoeDescription &, const ShoeDescription &);
+
     int m_size = 0;
     QColor m_color;
     QString m_brand;

examples/qml/tutorials/extending-qml-advanced/advanced7-Foreign-objects-integration/person.cpp

@@ -60,6 +60,12 @@ void ShoeDescription::setPrice(qreal price)
     }
 }
 
+bool ShoeDescription::operatorEqualsImpl(const ShoeDescription &lhs, const ShoeDescription &rhs)
+{
+    return lhs.m_size == rhs.m_size && lhs.m_color == rhs.m_color && lhs.m_brand == rhs.m_brand
+            && lhs.m_price == rhs.m_price;
+}
+
 QString Person::name() const
 {
     return m_name;
@@ -80,7 +86,10 @@ ShoeDescription *Person::shoe() const
 
 void Person::setShoe(ShoeDescription *shoe)
 {
-    if (m_shoe != shoe) {
+    if (!shoe)
+        return;
+
+    if (*m_shoe != *shoe) {
         m_shoe = shoe;
         emit shoeChanged();
     }

examples/qml/tutorials/extending-qml-advanced/advanced7-Foreign-objects-integration/person.h

@@ -31,10 +31,21 @@ public:
     qreal price() const;
     void setPrice(qreal);
 
+    friend bool operator==(const ShoeDescription &lhs, const ShoeDescription &rhs)
+    {
+        return operatorEqualsImpl(lhs, rhs);
+    }
+    friend bool operator!=(const ShoeDescription &lhs, const ShoeDescription &rhs)
+    {
+        return !operatorEqualsImpl(lhs, rhs);
+    }
+
 signals:
     void shoeChanged();
 
 private:
+    static bool operatorEqualsImpl(const ShoeDescription &, const ShoeDescription &);
+
     int m_size = 0;
     QColor m_color;
     QString m_brand;