1 files changed, 79 insertions, 0 deletions
diff --git a/examples/corelib/bindableproperties/subscription/subscription.cpp b/examples/corelib/bindableproperties/subscription/subscription.cpp
new file mode 100644
index 0000000000..85cc5798cc
--- /dev/null
+++ b/examples/corelib/bindableproperties/subscription/subscription.cpp
@@ -0,0 +1,79 @@
+// Copyright (C) 2021 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#include "subscription.h"
+#include "user.h"
+
+Subscription::Subscription(User *user) : m_user(user)
+{
+    Q_ASSERT(user);
+}
+
+//! [calculate-price]
+
+void Subscription::calculatePrice()
+{
+    const auto oldPrice = m_price;
+
+    m_price = qRound(calculateDiscount() * int(m_duration) * basePrice());
+    if (m_price != oldPrice)
+        emit priceChanged();
+}
+
+//! [calculate-price]
+
+//! [set-duration]
+
+void Subscription::setDuration(Duration newDuration)
+{
+    if (newDuration != m_duration) {
+        m_duration = newDuration;
+        calculatePrice();
+        emit durationChanged();
+    }
+}
+
+//! [set-duration]
+
+//! [calculate-discount]
+
+double Subscription::calculateDiscount() const
+{
+    switch (m_duration) {
+    case Monthly:
+        return 1;
+    case Quarterly:
+        return 0.9;
+    case Yearly:
+        return 0.6;
+    }
+    Q_ASSERT(false);
+    return -1;
+}
+
+//! [calculate-discount]
+
+//! [calculate-base-price]
+
+int Subscription::basePrice() const
+{
+    if (m_user->country() == User::Country::AnyTerritory)
+        return 0;
+
+    return (m_user->country() == User::Country::Norway) ? 100 : 80;
+}
+
+//! [calculate-base-price]
+
+//! [update-validity]
+
+void Subscription::updateValidity()
+{
+    bool isValid = m_isValid;
+    m_isValid = m_user->country() != User::Country::AnyTerritory && m_user->age() > 12;
+
+    if (m_isValid != isValid)
+        emit isValidChanged();
+}
+
+//! [update-validity]