Repurpose ExclusiveGroup to ButtonGroup

This is another way of solving the naming clash with Qt Quick Controls,
and narrows our focus to the types of controls that actually make sense
to have in an "exclusive" group; buttons (Android calls them
"selection controls").

Change-Id: Icf6efe583fe784c3594de8635be84bbf757a55cd
Reviewed-by: J-P Nurmi <jpnurmi@theqtcompany.com>

1 files changed, 379 insertions, 0 deletions

diff --git a/src/templates/qquickbuttongroup.cpp b/src/templates/qquickbuttongroup.cpp
new file mode 100644
index 00000000..6fddcbc4
--- /dev/null
+++ b/src/templates/qquickbuttongroup.cpp
@@ -0,0 +1,379 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the Qt Labs Templates module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPLv3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qquickbuttongroup_p.h"
+
+#include <QtCore/private/qobject_p.h>
+#include <QtCore/qmetaobject.h>
+#include <QtCore/qvariant.h>
+#include <QtQml/qqmlinfo.h>
+
+#include "qquickabstractbutton_p_p.h"
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \qmltype ButtonGroup
+    \inherits QtObject
+    \instantiates QQuickButtonGroup
+    \inqmlmodule Qt.labs.controls
+    \ingroup utilities
+    \brief An exclusive group of checkable controls.
+
+    ButtonGroup is a non-visual, mutually exclusive group of buttons.
+    It is used with controls such as RadioButton, where only one of the options
+    can be selected at a time.
+
+    The most straight-forward way to use ButtonGroup is to assign
+    a list of buttons. For example, the list of children of a
+    \l{Item Positioners}{positioner} or a \l{Qt Quick Layouts}{layout}
+    that manages a group of mutually exclusive buttons.
+
+    \code
+    ButtonGroup {
+        buttons: column.children
+    }
+
+    Column {
+        id: column
+
+        RadioButton {
+            checked: true
+            text: qsTr("DAB")
+        }
+
+        RadioButton {
+            text: qsTr("FM")
+        }
+
+        RadioButton {
+            text: qsTr("AM")
+        }
+    }
+    \endcode
+
+    Mutually exclusive buttons do not always share the same parent item,
+    or the parent layout may sometimes contain items that should not be
+    included in the button group. Such cases are best handled using
+    the \l group attached property.
+
+    \code
+    ButtonGroup { id: radioGroup }
+
+    Column {
+        Label {
+            text: qsTr("Radio:")
+        }
+
+        RadioButton {
+            checked: true
+            text: qsTr("DAB")
+            ButtonGroup.group: radioGroup
+        }
+
+        RadioButton {
+            text: qsTr("FM")
+            ButtonGroup.group: radioGroup
+        }
+
+        RadioButton {
+            text: qsTr("AM")
+            ButtonGroup.group: radioGroup
+        }
+    }
+    \endcode
+
+    More advanced use cases can be handled using the addButton() and
+    removeButton() methods.
+
+    \sa RadioButton
+*/
+
+class QQuickButtonGroupPrivate : public QObjectPrivate
+{
+    Q_DECLARE_PUBLIC(QQuickButtonGroup)
+
+public:
+    QQuickButtonGroupPrivate() : checkedButton(Q_NULLPTR) { }
+
+    void clear();
+    void updateCurrent();
+
+    static void buttons_append(QQmlListProperty<QQuickAbstractButton> *prop, QQuickAbstractButton *obj);
+    static int buttons_count(QQmlListProperty<QQuickAbstractButton> *prop);
+    static QQuickAbstractButton *buttons_at(QQmlListProperty<QQuickAbstractButton> *prop, int index);
+    static void buttons_clear(QQmlListProperty<QQuickAbstractButton> *prop);
+
+    QQuickAbstractButton *checkedButton;
+    QVector<QQuickAbstractButton*> buttons;
+};
+
+void QQuickButtonGroupPrivate::clear()
+{
+    foreach (QQuickAbstractButton *button, buttons) {
+        QQuickAbstractButtonPrivate::get(button)->group = Q_NULLPTR;
+        QObjectPrivate::disconnect(button, &QQuickAbstractButton::checkedChanged, this, &QQuickButtonGroupPrivate::updateCurrent);
+    }
+    buttons.clear();
+}
+
+void QQuickButtonGroupPrivate::updateCurrent()
+{
+    Q_Q(QQuickButtonGroup);
+    QQuickAbstractButton *button = qobject_cast<QQuickAbstractButton*>(q->sender());
+    if (button && button->isChecked())
+        q->setCheckedButton(button);
+}
+
+void QQuickButtonGroupPrivate::buttons_append(QQmlListProperty<QQuickAbstractButton> *prop, QQuickAbstractButton *obj)
+{
+    QQuickButtonGroup *q = static_cast<QQuickButtonGroup *>(prop->object);
+    q->addButton(obj);
+}
+
+int QQuickButtonGroupPrivate::buttons_count(QQmlListProperty<QQuickAbstractButton> *prop)
+{
+    QQuickButtonGroupPrivate *p = static_cast<QQuickButtonGroupPrivate *>(prop->data);
+    return p->buttons.count();
+}
+
+QQuickAbstractButton *QQuickButtonGroupPrivate::buttons_at(QQmlListProperty<QQuickAbstractButton> *prop, int index)
+{
+    QQuickButtonGroupPrivate *p = static_cast<QQuickButtonGroupPrivate *>(prop->data);
+    return p->buttons.value(index);
+}
+
+void QQuickButtonGroupPrivate::buttons_clear(QQmlListProperty<QQuickAbstractButton> *prop)
+{
+    QQuickButtonGroupPrivate *p = static_cast<QQuickButtonGroupPrivate *>(prop->data);
+    if (!p->buttons.isEmpty()) {
+        p->clear();
+        QQuickButtonGroup *q = static_cast<QQuickButtonGroup *>(prop->object);
+        q->setCheckedButton(Q_NULLPTR);
+        emit q->buttonsChanged();
+    }
+}
+
+QQuickButtonGroup::QQuickButtonGroup(QObject *parent)
+    : QObject(*(new QQuickButtonGroupPrivate), parent)
+{
+}
+
+QQuickButtonGroup::~QQuickButtonGroup()
+{
+    Q_D(QQuickButtonGroup);
+    d->clear();
+}
+
+QQuickButtonGroupAttached *QQuickButtonGroup::qmlAttachedProperties(QObject *object)
+{
+    return new QQuickButtonGroupAttached(object);
+}
+
+/*!
+    \qmlproperty AbstractButton Qt.labs.controls::ButtonGroup::current
+
+    This property holds the currently selected button, or \c null if there is none.
+
+    By default, it is the first checked button added to the button group.
+*/
+QQuickAbstractButton *QQuickButtonGroup::checkedButton() const
+{
+    Q_D(const QQuickButtonGroup);
+    return d->checkedButton;
+}
+
+void QQuickButtonGroup::setCheckedButton(QQuickAbstractButton *checkedButton)
+{
+    Q_D(QQuickButtonGroup);
+    if (d->checkedButton != checkedButton) {
+        if (d->checkedButton)
+            d->checkedButton->setChecked(false);
+        d->checkedButton = checkedButton;
+        if (checkedButton)
+            checkedButton->setChecked(true);
+        emit checkedButtonChanged();
+    }
+}
+
+/*!
+    \qmlproperty list<Object> Qt.labs.controls::ButtonGroup::buttons
+    \default
+
+    This property holds the list of buttons.
+
+    \code
+    ButtonGroup {
+        buttons: column.children
+    }
+
+    Column {
+        id: column
+
+        RadioButton {
+            checked: true
+            text: qsTr("Option A")
+        }
+
+        RadioButton {
+            text: qsTr("Option B")
+        }
+    }
+    \endcode
+
+    \sa group
+*/
+QQmlListProperty<QQuickAbstractButton> QQuickButtonGroup::buttons()
+{
+    Q_D(QQuickButtonGroup);
+    return QQmlListProperty<QQuickAbstractButton>(this, d,
+        QQuickButtonGroupPrivate::buttons_append,
+        QQuickButtonGroupPrivate::buttons_count,
+        QQuickButtonGroupPrivate::buttons_at,
+        QQuickButtonGroupPrivate::buttons_clear);
+}
+
+/*!
+    \qmlmethod void Qt.labs.controls::ButtonGroup::addButton(AbstractButton button)
+
+    Adds a \a button to the button group.
+
+    \note Manually adding objects to a button group is typically unnecessary.
+          The \l buttons property and the \l group attached property provide a
+          convenient and declarative syntax.
+
+    \sa buttons, group
+*/
+void QQuickButtonGroup::addButton(QQuickAbstractButton *button)
+{
+    Q_D(QQuickButtonGroup);
+    if (!button || d->buttons.contains(button))
+        return;
+
+    QQuickAbstractButtonPrivate::get(button)->group = this;
+    QObjectPrivate::connect(button, &QQuickAbstractButton::checkedChanged, d, &QQuickButtonGroupPrivate::updateCurrent);
+
+    if (button->isChecked())
+        setCheckedButton(button);
+
+    d->buttons.append(button);
+    emit buttonsChanged();
+}
+
+/*!
+    \qmlmethod void Qt.labs.controls::ButtonGroup::removeButton(AbstractButton button)
+
+    Removes a \a button from the button group.
+
+    \note Manually removing objects from a button group is typically unnecessary.
+          The \l buttons property and the \l group attached property provide a
+          convenient and declarative syntax.
+
+    \sa buttons, group
+*/
+void QQuickButtonGroup::removeButton(QQuickAbstractButton *button)
+{
+    Q_D(QQuickButtonGroup);
+    if (!button || !d->buttons.contains(button))
+        return;
+
+    QQuickAbstractButtonPrivate::get(button)->group = Q_NULLPTR;
+    QObjectPrivate::disconnect(button, &QQuickAbstractButton::checkedChanged, d, &QQuickButtonGroupPrivate::updateCurrent);
+
+    if (d->checkedButton == button)
+        setCheckedButton(Q_NULLPTR);
+
+    d->buttons.removeOne(button);
+    emit buttonsChanged();
+}
+
+class QQuickButtonGroupAttachedPrivate : public QObjectPrivate
+{
+public:
+    QQuickButtonGroupAttachedPrivate() : group(Q_NULLPTR) { }
+
+    QQuickButtonGroup *group;
+};
+
+QQuickButtonGroupAttached::QQuickButtonGroupAttached(QObject *parent) :
+    QObject(*(new QQuickButtonGroupAttachedPrivate), parent)
+{
+}
+
+/*!
+    \qmlattachedproperty ButtonGroup Qt.labs.controls::ButtonGroup::group
+
+    This property attaches a button to a button group.
+
+    \code
+    ButtonGroup { id: group }
+
+    RadioButton {
+        checked: true
+        text: qsTr("Option A")
+        ButtonGroup.group: group
+    }
+
+    RadioButton {
+        text: qsTr("Option B")
+        ButtonGroup.group: group
+    }
+    \endcode
+
+    \sa buttons
+*/
+QQuickButtonGroup *QQuickButtonGroupAttached::group() const
+{
+    Q_D(const QQuickButtonGroupAttached);
+    return d->group;
+}
+
+void QQuickButtonGroupAttached::setGroup(QQuickButtonGroup *group)
+{
+    Q_D(QQuickButtonGroupAttached);
+    if (d->group != group) {
+        if (d->group)
+            d->group->removeButton(qobject_cast<QQuickAbstractButton*>(parent()));
+        d->group = group;
+        if (group)
+            group->addButton(qobject_cast<QQuickAbstractButton*>(parent()));
+        emit groupChanged();
+    }
+}
+
+QT_END_NAMESPACE
+
+#include "moc_qquickbuttongroup_p.cpp"