qquicktabbar.cpp

Go to the documentation of this file.

// Copyright (C) 2017 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qquicktabbar_p.h"
#include "qquicktabbutton_p.h"
#include "qquickcontainer_p_p.h"
 
QT_BEGIN_NAMESPACE
 
 
class QQuickTabBarPrivate : public QQuickContainerPrivate
{
public:
    Q_DECLARE_PUBLIC(QQuickTabBar)
 
    void updateCurrentItem();
    void updateCurrentIndex();
    void updateLayout();
 
    qreal getContentWidth() const override;
    qreal getContentHeight() const override;
 
    void itemGeometryChanged(QQuickItem *item, QQuickGeometryChange change, const QRectF &diff) override;
    void itemImplicitWidthChanged(QQuickItem *item) override;
    void itemImplicitHeightChanged(QQuickItem *item) override;
 
    QPalette defaultPalette() const override { return QQuickTheme::palette(QQuickTheme::TabBar); }
 
    bool updatingLayout = false;
    QQuickTabBar::Position position = QQuickTabBar::Header;
#if QT_CONFIG(wheelevent)
    QPoint accumulatedAngleDelta;
#endif
};
 
class QQuickTabBarAttachedPrivate : public QObjectPrivate
{
    Q_DECLARE_PUBLIC(QQuickTabBarAttached)
 
public:
    static QQuickTabBarAttachedPrivate *get(QQuickTabBarAttached *attached)
    {
        return attached->d_func();
    }
 
    void update(QQuickTabBar *tabBar, int index);
 
    int index = -1;
    QQuickTabBar *tabBar = nullptr;
};
 
void QQuickTabBarPrivate::updateCurrentItem()
{
    QQuickTabButton *button = qobject_cast<QQuickTabButton *>(contentModel->get(currentIndex));
    if (button)
        button->setChecked(true);
}
 
void QQuickTabBarPrivate::updateCurrentIndex()
{
    Q_Q(QQuickTabBar);
    QQuickTabButton *button = qobject_cast<QQuickTabButton *>(q->sender());
    if (button && button->isChecked())
        q->setCurrentIndex(contentModel->indexOf(button, nullptr));
}
 
void QQuickTabBarPrivate::updateLayout()
{
    Q_Q(QQuickTabBar);
    const int count = contentModel->count();
    if (count <= 0 || !contentItem)
        return;
 
    qreal reservedWidth = 0;
    int resizableCount = 0;
 
    QList<QQuickItem *> allItems;
    allItems.reserve(count);
 
    for (int i = 0; i < count; ++i) {
        QQuickItem *item = q->itemAt(i);
        if (item) {
            QQuickItemPrivate *p = QQuickItemPrivate::get(item);
            if (!p->widthValid())
                ++resizableCount;
            else
                reservedWidth += item->width();
            allItems += item;
        }
    }
 
    const qreal totalSpacing = qMax(0, count - 1) * spacing;
    const qreal itemWidth = (contentItem->width() - reservedWidth - totalSpacing) / qMax(1, resizableCount);
 
    updatingLayout = true;
    for (QQuickItem *item : std::as_const(allItems)) {
        QQuickItemPrivate *p = QQuickItemPrivate::get(item);
        if (!p->widthValid()) {
            item->setWidth(itemWidth);
            p->widthValidFlag = false;
        }
        if (!p->heightValid()) {
            item->setHeight(contentHeight);
            p->heightValidFlag = false;
        } else {
            item->setY((contentHeight - item->height()) / 2);
        }
    }
    updatingLayout = false;
}
 
qreal QQuickTabBarPrivate::getContentWidth() const
{
    Q_Q(const QQuickTabBar);
    const int count = contentModel->count();
    qreal totalWidth = qMax(0, count - 1) * spacing;
    for (int i = 0; i < count; ++i) {
        QQuickItem *item = q->itemAt(i);
        if (item) {
            QQuickItemPrivate *p = QQuickItemPrivate::get(item);
            if (!p->widthValid())
                totalWidth += item->implicitWidth();
            else
                totalWidth += item->width();
        }
    }
    return totalWidth;
}
 
qreal QQuickTabBarPrivate::getContentHeight() const
{
    Q_Q(const QQuickTabBar);
    const int count = contentModel->count();
    qreal maxHeight = 0;
    for (int i = 0; i < count; ++i) {
        QQuickItem *item = q->itemAt(i);
        if (item)
            maxHeight = qMax(maxHeight, item->implicitHeight());
    }
    return maxHeight;
}
 
void QQuickTabBarPrivate::itemGeometryChanged(QQuickItem *item, QQuickGeometryChange change, const QRectF &diff)
{
    QQuickContainerPrivate::itemGeometryChanged(item, change, diff);
    if (!updatingLayout) {
        if (change.sizeChange())
            updateImplicitContentSize();
        updateLayout();
    }
}
 
void QQuickTabBarPrivate::itemImplicitWidthChanged(QQuickItem *item)
{
    QQuickContainerPrivate::itemImplicitWidthChanged(item);
    if (item != contentItem)
        updateImplicitContentWidth();
}
 
void QQuickTabBarPrivate::itemImplicitHeightChanged(QQuickItem *item)
{
    QQuickContainerPrivate::itemImplicitHeightChanged(item);
    if (item != contentItem)
        updateImplicitContentHeight();
}
 
QQuickTabBar::QQuickTabBar(QQuickItem *parent)
    : QQuickContainer(*(new QQuickTabBarPrivate), parent)
{
    Q_D(QQuickTabBar);
    d->changeTypes |= QQuickItemPrivate::Geometry | QQuickItemPrivate::ImplicitWidth | QQuickItemPrivate::ImplicitHeight;
    setFlag(ItemIsFocusScope);
    QObjectPrivate::connect(this, &QQuickTabBar::currentIndexChanged, d, &QQuickTabBarPrivate::updateCurrentItem);
}
 
QQuickTabBar::Position QQuickTabBar::position() const
{
    Q_D(const QQuickTabBar);
    return d->position;
}
 
void QQuickTabBar::setPosition(Position position)
{
    Q_D(QQuickTabBar);
    if (d->position == position)
        return;
 
    d->position = position;
    emit positionChanged();
}
 
QQuickTabBarAttached *QQuickTabBar::qmlAttachedProperties(QObject *object)
{
    return new QQuickTabBarAttached(object);
}
 
void QQuickTabBar::updatePolish()
{
    Q_D(QQuickTabBar);
    QQuickContainer::updatePolish();
    d->updateLayout();
}
 
void QQuickTabBar::componentComplete()
{
    Q_D(QQuickTabBar);
    QQuickContainer::componentComplete();
    d->updateCurrentItem();
    d->updateLayout();
}
 
void QQuickTabBar::geometryChange(const QRectF &newGeometry, const QRectF &oldGeometry)
{
    Q_D(QQuickTabBar);
    QQuickContainer::geometryChange(newGeometry, oldGeometry);
    d->updateLayout();
}
 
bool QQuickTabBar::isContent(QQuickItem *item) const
{
    return qobject_cast<QQuickTabButton *>(item);
}
 
void QQuickTabBar::itemAdded(int index, QQuickItem *item)
{
    Q_D(QQuickTabBar);
    Q_UNUSED(index);
    QQuickItemPrivate::get(item)->setCulled(true); // QTBUG-55129
    if (QQuickTabButton *button = qobject_cast<QQuickTabButton *>(item))
        QObjectPrivate::connect(button, &QQuickTabButton::checkedChanged, d, &QQuickTabBarPrivate::updateCurrentIndex);
    QQuickTabBarAttached *attached = qobject_cast<QQuickTabBarAttached *>(qmlAttachedPropertiesObject<QQuickTabBar>(item));
    if (attached)
        QQuickTabBarAttachedPrivate::get(attached)->update(this, index);
    d->updateImplicitContentSize();
    if (isComponentComplete())
        polish();
}
 
void QQuickTabBar::itemMoved(int index, QQuickItem *item)
{
    QQuickTabBarAttached *attached = qobject_cast<QQuickTabBarAttached *>(qmlAttachedPropertiesObject<QQuickTabBar>(item));
    if (attached)
        QQuickTabBarAttachedPrivate::get(attached)->update(this, index);
}
 
void QQuickTabBar::itemRemoved(int index, QQuickItem *item)
{
    Q_D(QQuickTabBar);
    Q_UNUSED(index);
    if (QQuickTabButton *button = qobject_cast<QQuickTabButton *>(item))
        QObjectPrivate::disconnect(button, &QQuickTabButton::checkedChanged, d, &QQuickTabBarPrivate::updateCurrentIndex);
    QQuickTabBarAttached *attached = qobject_cast<QQuickTabBarAttached *>(qmlAttachedPropertiesObject<QQuickTabBar>(item));
    if (attached)
        QQuickTabBarAttachedPrivate::get(attached)->update(nullptr, -1);
    d->updateImplicitContentSize();
    if (isComponentComplete())
        polish();
}
 
#if QT_CONFIG(wheelevent)
void QQuickTabBar::wheelEvent(QWheelEvent *event)
{
    Q_D(QQuickTabBar);
    QQuickContainer::wheelEvent(event);
    if (d->wheelEnabled) {
        d->accumulatedAngleDelta += event->angleDelta();
        int xSteps = d->accumulatedAngleDelta.x() / QWheelEvent::DefaultDeltasPerStep;
        int ySteps = d->accumulatedAngleDelta.y() / QWheelEvent::DefaultDeltasPerStep;
        if (xSteps > 0 || ySteps > 0) {
            decrementCurrentIndex();
            d->accumulatedAngleDelta = QPoint();
        } else if (xSteps < 0 || ySteps < 0) {
            incrementCurrentIndex();
            d->accumulatedAngleDelta = QPoint();
        }
    }
}
#endif
 
QFont QQuickTabBar::defaultFont() const
{
    return QQuickTheme::font(QQuickTheme::TabBar);
}
 
#if QT_CONFIG(accessibility)
QAccessible::Role QQuickTabBar::accessibleRole() const
{
    return QAccessible::PageTabList;
}
#endif
 
void QQuickTabBarAttachedPrivate::update(QQuickTabBar *newTabBar, int newIndex)
{
    Q_Q(QQuickTabBarAttached);
    const int oldIndex = index;
    const QQuickTabBar *oldTabBar = tabBar;
    const QQuickTabBar::Position oldPos = q->position();
 
    index = newIndex;
    tabBar = newTabBar;
 
    if (oldTabBar != newTabBar) {
        if (oldTabBar)
            QObject::disconnect(oldTabBar, &QQuickTabBar::positionChanged, q, &QQuickTabBarAttached::positionChanged);
        if (newTabBar)
            QObject::connect(newTabBar, &QQuickTabBar::positionChanged, q, &QQuickTabBarAttached::positionChanged);
        emit q->tabBarChanged();
    }
 
    if (oldIndex != newIndex)
        emit q->indexChanged();
    if (oldPos != q->position())
        emit q->positionChanged();
}
 
QQuickTabBarAttached::QQuickTabBarAttached(QObject *parent)
    : QObject(*(new QQuickTabBarAttachedPrivate), parent)
{
}
 
int QQuickTabBarAttached::index() const
{
    Q_D(const QQuickTabBarAttached);
    return d->index;
}
 
QQuickTabBar *QQuickTabBarAttached::tabBar() const
{
    Q_D(const QQuickTabBarAttached);
    return d->tabBar;
}
 
QQuickTabBar::Position QQuickTabBarAttached::position() const
{
    Q_D(const QQuickTabBarAttached);
    if (!d->tabBar)
        return QQuickTabBar::Header;
    return d->tabBar->position();
}
 
QT_END_NAMESPACE
 
#include "moc_qquicktabbar_p.cpp"