Add ButtonGroup::clicked(AbstractButton) signal

[ChangeLog][ButtonGroup] Added clicked(AbstractButton) signal
for centralized click handling for grouped buttons.

Change-Id: Ib64d360db211d2763f6237e411152a2a395fd2b5
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

5 files changed, 72 insertions, 0 deletions

diff --git a/src/imports/controls/qtquickcontrols2plugin.cpp b/src/imports/controls/qtquickcontrols2plugin.cpp
index 756467e5..db12cbb5 100644
--- a/src/imports/controls/qtquickcontrols2plugin.cpp
+++ b/src/imports/controls/qtquickcontrols2plugin.cpp
@@ -136,6 +136,7 @@ void QtQuickControls2Plugin::registerTypes(const char *uri)
     qmlRegisterType(selector.select(QStringLiteral("Tumbler.qml")), uri, 2, 0, "Tumbler");
 
     // QtQuick.Controls 2.1 (Qt 5.8)
+    qmlRegisterType<QQuickButtonGroup,1 >(uri, 2, 1, "ButtonGroup");
     qmlRegisterType(selector.select(QStringLiteral("StackView.qml")), uri, 2, 1, "StackView");
     qmlRegisterType(selector.select(QStringLiteral("SwipeView.qml")), uri, 2, 1, "SwipeView");
 }
diff --git a/src/imports/templates/qtquicktemplates2plugin.cpp b/src/imports/templates/qtquicktemplates2plugin.cpp
index bfd3a71b..92082f8a 100644
--- a/src/imports/templates/qtquicktemplates2plugin.cpp
+++ b/src/imports/templates/qtquicktemplates2plugin.cpp
@@ -173,6 +173,7 @@ void QtQuickTemplates2Plugin::registerTypes(const char *uri)
     qmlRegisterRevision<QQuickTextEdit, 7>(uri, 2, 0);
 
     // QtQuick.Controls 2.1 (Qt 5.8)
+    qmlRegisterType<QQuickButtonGroup>(uri, 2, 1, "ButtonGroup");
     qmlRegisterType<QQuickStackView>(uri, 2, 1, "StackView");
     qmlRegisterType<QQuickSwipeView>(uri, 2, 1, "SwipeView");
 }
diff --git a/src/quicktemplates2/qquickbuttongroup.cpp b/src/quicktemplates2/qquickbuttongroup.cpp
index 0b134267..bc9a092f 100644
--- a/src/quicktemplates2/qquickbuttongroup.cpp
+++ b/src/quicktemplates2/qquickbuttongroup.cpp
@@ -123,6 +123,32 @@ QT_BEGIN_NAMESPACE
     \sa RadioButton
 */
 
+/*!
+    \qmlsignal QtQuick.Controls::ButtonGroup::clicked(AbstractButton button)
+    \since QtQuick.Controls 2.1
+
+    This signal is emitted when a \a button in the group has been clicked.
+
+    This signal is convenient for implementing a common signal handler for
+    all buttons in the same group.
+
+    \code
+    ButtonGroup {
+        buttons: column.children
+        onClicked: console.log("clicked:", button.text)
+    }
+
+    Column {
+        id: column
+        Button { text: "First" }
+        Button { text: "Second" }
+        Button { text: "Third" }
+    }
+    \endcode
+
+    \sa AbstractButton::clicked()
+*/
+
 class QQuickButtonGroupPrivate : public QObjectPrivate
 {
     Q_DECLARE_PUBLIC(QQuickButtonGroup)
@@ -131,6 +157,7 @@ public:
     QQuickButtonGroupPrivate() : checkedButton(nullptr) { }
 
     void clear();
+    void buttonClicked();
     void _q_updateCurrent();
 
     static void buttons_append(QQmlListProperty<QQuickAbstractButton> *prop, QQuickAbstractButton *obj);
@@ -146,11 +173,20 @@ void QQuickButtonGroupPrivate::clear()
 {
     for (QQuickAbstractButton *button : qAsConst(buttons)) {
         QQuickAbstractButtonPrivate::get(button)->group = nullptr;
+        QObjectPrivate::disconnect(button, &QQuickAbstractButton::clicked, this, &QQuickButtonGroupPrivate::buttonClicked);
         QObjectPrivate::disconnect(button, &QQuickAbstractButton::checkedChanged, this, &QQuickButtonGroupPrivate::_q_updateCurrent);
     }
     buttons.clear();
 }
 
+void QQuickButtonGroupPrivate::buttonClicked()
+{
+    Q_Q(QQuickButtonGroup);
+    QQuickAbstractButton *button = qobject_cast<QQuickAbstractButton*>(q->sender());
+    if (button)
+        emit q->clicked(button);
+}
+
 void QQuickButtonGroupPrivate::_q_updateCurrent()
 {
     Q_Q(QQuickButtonGroup);
@@ -289,6 +325,7 @@ void QQuickButtonGroup::addButton(QQuickAbstractButton *button)
         return;
 
     QQuickAbstractButtonPrivate::get(button)->group = this;
+    QObjectPrivate::connect(button, &QQuickAbstractButton::clicked, d, &QQuickButtonGroupPrivate::buttonClicked);
     QObjectPrivate::connect(button, &QQuickAbstractButton::checkedChanged, d, &QQuickButtonGroupPrivate::_q_updateCurrent);
 
     if (button->isChecked())
@@ -316,6 +353,7 @@ void QQuickButtonGroup::removeButton(QQuickAbstractButton *button)
         return;
 
     QQuickAbstractButtonPrivate::get(button)->group = nullptr;
+    QObjectPrivate::disconnect(button, &QQuickAbstractButton::clicked, d, &QQuickButtonGroupPrivate::buttonClicked);
     QObjectPrivate::disconnect(button, &QQuickAbstractButton::checkedChanged, d, &QQuickButtonGroupPrivate::_q_updateCurrent);
 
     if (d->checkedButton == button)
diff --git a/src/quicktemplates2/qquickbuttongroup_p.h b/src/quicktemplates2/qquickbuttongroup_p.h
index baf4e13f..2202ae2f 100644
--- a/src/quicktemplates2/qquickbuttongroup_p.h
+++ b/src/quicktemplates2/qquickbuttongroup_p.h
@@ -83,6 +83,7 @@ public Q_SLOTS:
 Q_SIGNALS:
     void checkedButtonChanged();
     void buttonsChanged();
+    Q_REVISION(1) void clicked(QQuickAbstractButton *button);
 
 private:
     Q_DISABLE_COPY(QQuickButtonGroup)
diff --git a/tests/auto/controls/data/tst_buttongroup.qml b/tests/auto/controls/data/tst_buttongroup.qml
index bb0ffe00..91bc3aa1 100644
--- a/tests/auto/controls/data/tst_buttongroup.qml
+++ b/tests/auto/controls/data/tst_buttongroup.qml
@@ -65,6 +65,11 @@ TestCase {
         signalName: "buttonsChanged"
     }
 
+    SignalSpy {
+        id: clickedSpy
+        signalName: "clicked"
+    }
+
     function init() {
         verify(!checkedButtonSpy.target)
         compare(checkedButtonSpy.count, 0)
@@ -217,6 +222,32 @@ TestCase {
         group.destroy()
     }
 
+    function test_clicked() {
+        var group = buttonGroup.createObject(testCase)
+        verify(group)
+
+        clickedSpy.target = group
+        verify(clickedSpy.valid)
+
+        var button1 = button.createObject(testCase)
+        var button2 = button.createObject(testCase)
+
+        group.addButton(button1)
+        group.addButton(button2)
+
+        button1.clicked()
+        compare(clickedSpy.count, 1)
+        compare(clickedSpy.signalArguments[0][0], button1)
+
+        button2.clicked()
+        compare(clickedSpy.count, 2)
+        compare(clickedSpy.signalArguments[1][0], button2)
+
+        group.destroy()
+        button1.destroy()
+        button2.destroy()
+    }
+
     Component {
         id: checkBoxes
         Item {