qquicklabel.cpp

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// 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 "qquicklabel_p.h"
#include "qquicklabel_p_p.h"
#include "qquickcontrol_p.h"
#include "qquickcontrol_p_p.h"
#include "qquickdeferredexecute_p_p.h"
 
#include <QtQuick/private/qquickitem_p.h>
#include <QtQuick/private/qquicktext_p.h>
 
#if QT_CONFIG(accessibility)
#include <QtQuick/private/qquickaccessibleattached_p.h>
#endif
 
QT_BEGIN_NAMESPACE
 
/*!
    \qmltype Label
    \inherits Text
//!     \nativetype QQuickLabel
    \inqmlmodule QtQuick.Controls
    \since 5.7
    \ingroup text
    \brief Styled text label with inherited font.
 
    Label extends \l Text with styling and \l {Control::font}{font}
    inheritance. The default colors and font are style specific. Label
    can also have a visual \l background item.
 
    \image qtquickcontrols-label.png
 
    \snippet qtquickcontrols-label.qml 1
 
    You can use the properties of \l Text to change the appearance of the text as desired:
 
    \qml
     Label {
         text: "Hello world"
         font.pixelSize: 22
         font.italic: true
     }
    \endqml
 
    \sa {Customizing Label}
*/
 
QQuickLabelPrivate::QQuickLabelPrivate()
{
#if QT_CONFIG(accessibility)
    QAccessible::installActivationObserver(this);
#endif
}
 
QQuickLabelPrivate::~QQuickLabelPrivate()
{
#if QT_CONFIG(accessibility)
    QAccessible::removeActivationObserver(this);
#endif
}
 
void QQuickLabelPrivate::setTopInset(qreal value, bool reset)
{
    Q_Q(QQuickLabel);
    const QMarginsF oldInset = getInset();
    extra.value().topInset = value;
    extra.value().hasTopInset = !reset;
    if (!qFuzzyCompare(oldInset.top(), value)) {
        emit q->topInsetChanged();
        q->insetChange(getInset(), oldInset);
    }
}
 
void QQuickLabelPrivate::setLeftInset(qreal value, bool reset)
{
    Q_Q(QQuickLabel);
    const QMarginsF oldInset = getInset();
    extra.value().leftInset = value;
    extra.value().hasLeftInset = !reset;
    if (!qFuzzyCompare(oldInset.left(), value)) {
        emit q->leftInsetChanged();
        q->insetChange(getInset(), oldInset);
    }
}
 
void QQuickLabelPrivate::setRightInset(qreal value, bool reset)
{
    Q_Q(QQuickLabel);
    const QMarginsF oldInset = getInset();
    extra.value().rightInset = value;
    extra.value().hasRightInset = !reset;
    if (!qFuzzyCompare(oldInset.right(), value)) {
        emit q->rightInsetChanged();
        q->insetChange(getInset(), oldInset);
    }
}
 
void QQuickLabelPrivate::setBottomInset(qreal value, bool reset)
{
    Q_Q(QQuickLabel);
    const QMarginsF oldInset = getInset();
    extra.value().bottomInset = value;
    extra.value().hasBottomInset = !reset;
    if (!qFuzzyCompare(oldInset.bottom(), value)) {
        emit q->bottomInsetChanged();
        q->insetChange(getInset(), oldInset);
    }
}
 
void QQuickLabelPrivate::resizeBackground()
{
    if (!background)
        return;
 
    resizingBackground = true;
 
    QQuickItemPrivate *p = QQuickItemPrivate::get(background);
    if (((!p->widthValid() || !extra.isAllocated() || !extra->hasBackgroundWidth) && qFuzzyIsNull(background->x()))
            || (extra.isAllocated() && (extra->hasLeftInset || extra->hasRightInset))) {
        background->setX(getLeftInset());
        background->setWidth(width - getLeftInset() - getRightInset());
    }
    if (((!p->heightValid() || !extra.isAllocated() || !extra->hasBackgroundHeight) && qFuzzyIsNull(background->y()))
            || (extra.isAllocated() && (extra->hasTopInset || extra->hasBottomInset))) {
        background->setY(getTopInset());
        background->setHeight(height - getTopInset() - getBottomInset());
    }
 
    resizingBackground = false;
}
 
/*!
    \internal
 
    Determine which font is implicitly imposed on this control by its ancestors
    and QGuiApplication::font, resolve this against its own font (attributes from
    the implicit font are copied over). Then propagate this font to this
    control's children.
*/
void QQuickLabelPrivate::resolveFont()
{
    Q_Q(QQuickLabel);
    inheritFont(QQuickControlPrivate::parentFont(q));
}
 
void QQuickLabelPrivate::inheritFont(const QFont &font)
{
    QFont parentFont = extra.isAllocated() ? extra->requestedFont.resolve(font) : font;
    parentFont.setResolveMask(extra.isAllocated() ? extra->requestedFont.resolveMask() | font.resolveMask() : font.resolveMask());
 
    const QFont defaultFont = QQuickTheme::font(QQuickTheme::Label);
    QFont resolvedFont = parentFont.resolve(defaultFont);
 
    setFont_helper(resolvedFont);
}
 
/*!
    \internal
 
    Assign \a font to this control, and propagate it to all children.
*/
void QQuickLabelPrivate::updateFont(const QFont &font)
{
    Q_Q(QQuickLabel);
    QFont oldFont = sourceFont;
    q->QQuickText::setFont(font);
 
    QQuickControlPrivate::updateFontRecur(q, font);
 
    if (oldFont != font)
        emit q->fontChanged();
}
 
void QQuickLabelPrivate::textChanged(const QString &text)
{
#if QT_CONFIG(accessibility)
    maybeSetAccessibleName(text);
#else
    Q_UNUSED(text);
#endif
}
 
#if QT_CONFIG(accessibility)
void QQuickLabelPrivate::accessibilityActiveChanged(bool active)
{
    if (!active)
        return;
 
    Q_Q(QQuickLabel);
    QQuickAccessibleAttached *accessibleAttached = qobject_cast<QQuickAccessibleAttached *>(qmlAttachedPropertiesObject<QQuickAccessibleAttached>(q, true));
    Q_ASSERT(accessibleAttached);
    accessibleAttached->setRole(effectiveAccessibleRole());
    maybeSetAccessibleName(text);
}
 
QAccessible::Role QQuickLabelPrivate::accessibleRole() const
{
    return QAccessible::StaticText;
}
 
void QQuickLabelPrivate::maybeSetAccessibleName(const QString &name)
{
    Q_Q(QQuickLabel);
    auto accessibleAttached = qobject_cast<QQuickAccessibleAttached *>(
        qmlAttachedPropertiesObject<QQuickAccessibleAttached>(q, true));
    if (accessibleAttached) {
        if (!accessibleAttached->wasNameExplicitlySet())
            accessibleAttached->setNameImplicitly(name);
    }
}
#endif
 
void QQuickLabelPrivate::cancelBackground()
{
    Q_Q(QQuickLabel);
    quickCancelDeferred(q, backgroundName());
}
 
void QQuickLabelPrivate::executeBackground(bool complete)
{
    Q_Q(QQuickLabel);
    if (background.wasExecuted())
        return;
 
    if (!background || complete)
        quickBeginDeferred(q, backgroundName(), background);
    if (complete)
        quickCompleteDeferred(q, backgroundName(), background);
}
 
void QQuickLabelPrivate::itemGeometryChanged(QQuickItem *item, QQuickGeometryChange change, const QRectF &diff)
{
    Q_UNUSED(diff);
    if (resizingBackground || item != background || !change.sizeChange())
        return;
 
    QQuickItemPrivate *p = QQuickItemPrivate::get(item);
    extra.value().hasBackgroundWidth = p->widthValid();
    extra.value().hasBackgroundHeight = p->heightValid();
    resizeBackground();
}
 
void QQuickLabelPrivate::itemImplicitWidthChanged(QQuickItem *item)
{
    Q_Q(QQuickLabel);
    if (item == background)
        emit q->implicitBackgroundWidthChanged();
}
 
void QQuickLabelPrivate::itemImplicitHeightChanged(QQuickItem *item)
{
    Q_Q(QQuickLabel);
    if (item == background)
        emit q->implicitBackgroundHeightChanged();
}
 
void QQuickLabelPrivate::itemDestroyed(QQuickItem *item)
{
    Q_Q(QQuickLabel);
    if (item == background) {
        background = nullptr;
        emit q->implicitBackgroundWidthChanged();
        emit q->implicitBackgroundHeightChanged();
    }
}
 
QPalette QQuickLabelPrivate::defaultPalette() const
{
    return QQuickTheme::palette(QQuickTheme::Label);
}
 
QQuickLabel::QQuickLabel(QQuickItem *parent)
    : QQuickText(*(new QQuickLabelPrivate), parent)
{
    Q_D(QQuickLabel);
    QObjectPrivate::connect(this, &QQuickText::textChanged, d, &QQuickLabelPrivate::textChanged);
}
 
QQuickLabel::~QQuickLabel()
{
    Q_D(QQuickLabel);
    QQuickControlPrivate::removeImplicitSizeListener(d->background, d, QQuickControlPrivate::ImplicitSizeChanges | QQuickItemPrivate::Geometry);
}
 
QFont QQuickLabel::font() const
{
    Q_D(const QQuickLabel);
    QFont font = QQuickText::font();
    // The resolve mask should inherit from the requestedFont
    font.setResolveMask(d->extra.value().requestedFont.resolveMask());
    return font;
}
 
void QQuickLabel::setFont(const QFont &font)
{
    Q_D(QQuickLabel);
    if (d->extra.value().requestedFont.resolveMask() == font.resolveMask() && d->extra.value().requestedFont == font)
        return;
 
    d->extra.value().requestedFont = font;
    d->resolveFont();
}
 
/*!
    \qmlproperty Item QtQuick.Controls::Label::background
 
    This property holds the background item.
 
    \note If the background item has no explicit size specified, it automatically
          follows the control's size. In most cases, there is no need to specify
          width or height for a background item.
 
    \sa {Customizing Label}
*/
QQuickItem *QQuickLabel::background() const
{
    QQuickLabelPrivate *d = const_cast<QQuickLabelPrivate *>(d_func());
    if (!d->background)
        d->executeBackground();
    return d->background;
}
 
void QQuickLabel::setBackground(QQuickItem *background)
{
    Q_D(QQuickLabel);
    if (d->background == background)
        return;
 
    if (!d->background.isExecuting())
        d->cancelBackground();
 
    const qreal oldImplicitBackgroundWidth = implicitBackgroundWidth();
    const qreal oldImplicitBackgroundHeight = implicitBackgroundHeight();
 
    if (d->extra.isAllocated()) {
        d->extra.value().hasBackgroundWidth = false;
        d->extra.value().hasBackgroundHeight = false;
    }
 
    QQuickControlPrivate::removeImplicitSizeListener(d->background, d, QQuickControlPrivate::ImplicitSizeChanges | QQuickItemPrivate::Geometry);
    QQuickControlPrivate::hideOldItem(d->background);
    d->background = background;
 
    if (background) {
        background->setParentItem(this);
        if (qFuzzyIsNull(background->z()))
            background->setZ(-1);
        QQuickItemPrivate *p = QQuickItemPrivate::get(background);
        if (p->widthValid() || p->heightValid()) {
            d->extra.value().hasBackgroundWidth = p->widthValid();
            d->extra.value().hasBackgroundHeight = p->heightValid();
        }
        if (isComponentComplete())
            d->resizeBackground();
        QQuickControlPrivate::addImplicitSizeListener(background, d, QQuickControlPrivate::ImplicitSizeChanges | QQuickItemPrivate::Geometry);
    }
 
    if (!qFuzzyCompare(oldImplicitBackgroundWidth, implicitBackgroundWidth()))
        emit implicitBackgroundWidthChanged();
    if (!qFuzzyCompare(oldImplicitBackgroundHeight, implicitBackgroundHeight()))
        emit implicitBackgroundHeightChanged();
    if (!d->background.isExecuting())
        emit backgroundChanged();
}
 
/*!
    \since QtQuick.Controls 2.5 (Qt 5.12)
    \qmlproperty real QtQuick.Controls::Label::implicitBackgroundWidth
    \readonly
 
    This property holds the implicit background width.
 
    The value is equal to \c {background ? background.implicitWidth : 0}.
 
    \sa implicitBackgroundHeight
*/
qreal QQuickLabel::implicitBackgroundWidth() const
{
    Q_D(const QQuickLabel);
    if (!d->background)
        return 0;
    return d->background->implicitWidth();
}
 
/*!
    \since QtQuick.Controls 2.5 (Qt 5.12)
    \qmlproperty real QtQuick.Controls::Label::implicitBackgroundHeight
    \readonly
 
    This property holds the implicit background height.
 
    The value is equal to \c {background ? background.implicitHeight : 0}.
 
    \sa implicitBackgroundWidth
*/
qreal QQuickLabel::implicitBackgroundHeight() const
{
    Q_D(const QQuickLabel);
    if (!d->background)
        return 0;
    return d->background->implicitHeight();
}
 
/*!
    \since QtQuick.Controls 2.5 (Qt 5.12)
    \qmlproperty real QtQuick.Controls::Label::topInset
 
    This property holds the top inset for the background.
 
    \sa {Control Layout}, bottomInset
*/
qreal QQuickLabel::topInset() const
{
    Q_D(const QQuickLabel);
    return d->getTopInset();
}
 
void QQuickLabel::setTopInset(qreal inset)
{
    Q_D(QQuickLabel);
    d->setTopInset(inset);
}
 
void QQuickLabel::resetTopInset()
{
    Q_D(QQuickLabel);
    d->setTopInset(0, true);
}
 
/*!
    \since QtQuick.Controls 2.5 (Qt 5.12)
    \qmlproperty real QtQuick.Controls::Label::leftInset
 
    This property holds the left inset for the background.
 
    \sa {Control Layout}, rightInset
*/
qreal QQuickLabel::leftInset() const
{
    Q_D(const QQuickLabel);
    return d->getLeftInset();
}
 
void QQuickLabel::setLeftInset(qreal inset)
{
    Q_D(QQuickLabel);
    d->setLeftInset(inset);
}
 
void QQuickLabel::resetLeftInset()
{
    Q_D(QQuickLabel);
    d->setLeftInset(0, true);
}
 
/*!
    \since QtQuick.Controls 2.5 (Qt 5.12)
    \qmlproperty real QtQuick.Controls::Label::rightInset
 
    This property holds the right inset for the background.
 
    \sa {Control Layout}, leftInset
*/
qreal QQuickLabel::rightInset() const
{
    Q_D(const QQuickLabel);
    return d->getRightInset();
}
 
void QQuickLabel::setRightInset(qreal inset)
{
    Q_D(QQuickLabel);
    d->setRightInset(inset);
}
 
void QQuickLabel::resetRightInset()
{
    Q_D(QQuickLabel);
    d->setRightInset(0, true);
}
 
/*!
    \since QtQuick.Controls 2.5 (Qt 5.12)
    \qmlproperty real QtQuick.Controls::Label::bottomInset
 
    This property holds the bottom inset for the background.
 
    \sa {Control Layout}, topInset
*/
qreal QQuickLabel::bottomInset() const
{
    Q_D(const QQuickLabel);
    return d->getBottomInset();
}
 
void QQuickLabel::setBottomInset(qreal inset)
{
    Q_D(QQuickLabel);
    d->setBottomInset(inset);
}
 
void QQuickLabel::resetBottomInset()
{
    Q_D(QQuickLabel);
    d->setBottomInset(0, true);
}
 
void QQuickLabel::classBegin()
{
    Q_D(QQuickLabel);
    QQuickText::classBegin();
    d->resolveFont();
}
 
void QQuickLabel::componentComplete()
{
    Q_D(QQuickLabel);
    d->executeBackground(true);
    QQuickText::componentComplete();
    d->resizeBackground();
#if QT_CONFIG(accessibility)
    if (QAccessible::isActive())
        d->accessibilityActiveChanged(true);
#endif
}
 
void QQuickLabel::itemChange(QQuickItem::ItemChange change, const QQuickItem::ItemChangeData &value)
{
    Q_D(QQuickLabel);
    QQuickText::itemChange(change, value);
    switch (change) {
    case ItemEnabledHasChanged:
        break;
    case ItemSceneChange:
    case ItemParentHasChanged:
        if ((change == ItemParentHasChanged && value.item) || (change == ItemSceneChange && value.window)) {
            d->resolveFont();
        }
        break;
    default:
        break;
    }
}
 
void QQuickLabel::geometryChange(const QRectF &newGeometry, const QRectF &oldGeometry)
{
    Q_D(QQuickLabel);
    QQuickText::geometryChange(newGeometry, oldGeometry);
    d->resizeBackground();
}
 
void QQuickLabel::insetChange(const QMarginsF &newInset, const QMarginsF &oldInset)
{
    Q_D(QQuickLabel);
    Q_UNUSED(newInset);
    Q_UNUSED(oldInset);
    d->resizeBackground();
}
 
QT_END_NAMESPACE
 
#include "moc_qquicklabel_p.cpp"