qtdeclarative/src/quicktemplates2/qquickspinbox.cpp

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** Copyright (C) 2016 The Qt Company Ltd.
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** This file is part of the Qt Quick Templates 2 module of the Qt Toolkit.
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#include "qquickspinbox_p.h"
#include "qquickcontrol_p_p.h"

#include <QtGui/qguiapplication.h>
#include <QtGui/qstylehints.h>

#include <QtQml/qqmlinfo.h>
#include <QtQml/private/qqmllocale_p.h>
#include <QtQml/private/qqmlengine_p.h>

QT_BEGIN_NAMESPACE

// copied from qabstractbutton.cpp
static const int AUTO_REPEAT_DELAY = 300;
static const int AUTO_REPEAT_INTERVAL = 100;

/*!
    \qmltype SpinBox
    \inherits Control
    \instantiates QQuickSpinBox
    \inqmlmodule QtQuick.Controls
    \since 5.7
    \ingroup input
    \brief A spinbox control that allows the user to select from a set of preset values.

    \image qtquickcontrols2-spinbox.png

    SpinBox allows the user to choose an integer value by clicking the up
    or down indicator buttons, or by pressing up or down on the keyboard.
    Optionally, SpinBox can be also made \l editable, so the user can enter
    a text value in the input field.

    By default, SpinBox provides discrete values in the range of \c [0-99]
    with a \l stepSize of \c 1.

    \snippet qtquickcontrols2-spinbox.qml 1

    \section2 Custom Values

    \image qtquickcontrols2-spinbox-textual.png

    Even though SpinBox works on integer values, it can be customized to
    accept arbitrary input values. The following snippet demonstrates how
    \l validator, \l textFromValue and \l valueFromText can be used to
    customize the default behavior.

    \snippet qtquickcontrols2-spinbox-textual.qml 1

    In the same manner, SpinBox can be customized to accept floating point
    numbers:

    \image qtquickcontrols2-spinbox-double.png

    \snippet qtquickcontrols2-spinbox-double.qml 1

    \sa Tumbler, {Customizing SpinBox}
*/

class QQuickSpinBoxPrivate : public QQuickControlPrivate
{
    Q_DECLARE_PUBLIC(QQuickSpinBox)

public:
    QQuickSpinBoxPrivate() : editable(false), from(0), to(99), value(0), stepSize(1),
        delayTimer(0), repeatTimer(0), up(nullptr), down(nullptr), validator(nullptr) { }

    int boundValue(int value) const;
    void updateValue();

    int effectiveStepSize() const;

    bool upEnabled() const;
    void updateUpEnabled();
    bool downEnabled() const;
    void updateDownEnabled();

    void startRepeatDelay();
    void startPressRepeat();
    void stopPressRepeat();

    bool handleMousePressEvent(QQuickItem *child, QMouseEvent *event);
    bool handleMouseMoveEvent(QQuickItem *child, QMouseEvent *event);
    bool handleMouseReleaseEvent(QQuickItem *child, QMouseEvent *event);
    bool handleMouseUngrabEvent(QQuickItem *child);

    bool editable;
    int from;
    int to;
    int value;
    int stepSize;
    int delayTimer;
    int repeatTimer;
    QQuickSpinButton *up;
    QQuickSpinButton *down;
    QValidator *validator;
    mutable QJSValue textFromValue;
    mutable QJSValue valueFromText;
};

int QQuickSpinBoxPrivate::boundValue(int value) const
{
    return from > to ? qBound(to, value, from) : qBound(from, value, to);
}

void QQuickSpinBoxPrivate::updateValue()
{
    Q_Q(QQuickSpinBox);
    if (contentItem) {
        QVariant text = contentItem->property("text");
        if (text.isValid()) {
            QQmlEngine *engine = qmlEngine(q);
            if (engine) {
                QV4::ExecutionEngine *v4 = QQmlEnginePrivate::getV4Engine(engine);
                QJSValue loc(v4, QQmlLocale::wrap(v4, locale));
                QJSValue val = q->valueFromText().call(QJSValueList() << text.toString() << loc);
                q->setValue(val.toInt());
            }
        }
    }
}

int QQuickSpinBoxPrivate::effectiveStepSize() const
{
    return from > to ? -1 * stepSize : stepSize;
}

bool QQuickSpinBoxPrivate::upEnabled() const
{
    const QQuickItem *upIndicator = up->indicator();
    return upIndicator && upIndicator->isEnabled();
}

void QQuickSpinBoxPrivate::updateUpEnabled()
{
    QQuickItem *upIndicator = up->indicator();
    if (!upIndicator)
        return;

    upIndicator->setEnabled(from < to ? value < to : value > to);
}

bool QQuickSpinBoxPrivate::downEnabled() const
{
    const QQuickItem *downIndicator = down->indicator();
    return downIndicator && downIndicator->isEnabled();
}

void QQuickSpinBoxPrivate::updateDownEnabled()
{
    QQuickItem *downIndicator = down->indicator();
    if (!downIndicator)
        return;

    downIndicator->setEnabled(from < to ? value > from : value < from);
}

void QQuickSpinBoxPrivate::startRepeatDelay()
{
    Q_Q(QQuickSpinBox);
    stopPressRepeat();
    delayTimer = q->startTimer(AUTO_REPEAT_DELAY);
}

void QQuickSpinBoxPrivate::startPressRepeat()
{
    Q_Q(QQuickSpinBox);
    stopPressRepeat();
    repeatTimer = q->startTimer(AUTO_REPEAT_INTERVAL);
}

void QQuickSpinBoxPrivate::stopPressRepeat()
{
    Q_Q(QQuickSpinBox);
    if (delayTimer > 0) {
        q->killTimer(delayTimer);
        delayTimer = 0;
    }
    if (repeatTimer > 0) {
        q->killTimer(repeatTimer);
        repeatTimer = 0;
    }
}

bool QQuickSpinBoxPrivate::handleMousePressEvent(QQuickItem *child, QMouseEvent *event)
{
    Q_Q(QQuickSpinBox);
    QQuickItem *ui = up->indicator();
    QQuickItem *di = down->indicator();
    up->setPressed(ui && ui->isEnabled() && ui->contains(ui->mapFromItem(child, event->pos())));
    down->setPressed(di && di->isEnabled() && di->contains(di->mapFromItem(child, event->pos())));

    bool pressed = up->isPressed() || down->isPressed();
    q->setAccessibleProperty("pressed", pressed);
    if (pressed)
        startRepeatDelay();
    return pressed;
}

bool QQuickSpinBoxPrivate::handleMouseMoveEvent(QQuickItem *child, QMouseEvent *event)
{
    Q_Q(QQuickSpinBox);
    QQuickItem *ui = up->indicator();
    QQuickItem *di = down->indicator();
    up->setPressed(ui && ui->isEnabled() && ui->contains(ui->mapFromItem(child, event->pos())));
    down->setPressed(di && di->isEnabled() && di->contains(di->mapFromItem(child, event->pos())));

    bool pressed = up->isPressed() || down->isPressed();
    q->setAccessibleProperty("pressed", pressed);
    stopPressRepeat();
    return pressed;
}

bool QQuickSpinBoxPrivate::handleMouseReleaseEvent(QQuickItem *child, QMouseEvent *event)
{
    Q_Q(QQuickSpinBox);
    QQuickItem *ui = up->indicator();
    QQuickItem *di = down->indicator();
    bool wasPressed = up->isPressed() || down->isPressed();
    if (up->isPressed()) {
        up->setPressed(false);
        if (repeatTimer <= 0 && ui && ui->contains(ui->mapFromItem(child, event->pos())))
            q->increase();
    } else if (down->isPressed()) {
        down->setPressed(false);
        if (repeatTimer <= 0 && di && di->contains(di->mapFromItem(child, event->pos())))
            q->decrease();
    }

    q->setAccessibleProperty("pressed", false);
    stopPressRepeat();
    return wasPressed;
}

bool QQuickSpinBoxPrivate::handleMouseUngrabEvent(QQuickItem *)
{
    Q_Q(QQuickSpinBox);
    up->setPressed(false);
    down->setPressed(false);

    q->setAccessibleProperty("pressed", false);
    stopPressRepeat();
    return false;
}

QQuickSpinBox::QQuickSpinBox(QQuickItem *parent) :
    QQuickControl(*(new QQuickSpinBoxPrivate), parent)
{
    Q_D(QQuickSpinBox);
    d->up = new QQuickSpinButton(this);
    d->down = new QQuickSpinButton(this);

    setFlag(ItemIsFocusScope);
    setFiltersChildMouseEvents(true);
    setAcceptedMouseButtons(Qt::LeftButton);
}

/*!
    \qmlproperty int QtQuick.Controls::SpinBox::from

    This property holds the starting value for the range. The default value is \c 0.

    \sa to, value
*/
int QQuickSpinBox::from() const
{
    Q_D(const QQuickSpinBox);
    return d->from;
}

void QQuickSpinBox::setFrom(int from)
{
    Q_D(QQuickSpinBox);
    if (d->from == from)
        return;

    d->from = from;
    emit fromChanged();
    if (isComponentComplete())
        setValue(d->value);
}

/*!
    \qmlproperty int QtQuick.Controls::SpinBox::to

    This property holds the end value for the range. The default value is \c 99.

    \sa from, value
*/
int QQuickSpinBox::to() const
{
    Q_D(const QQuickSpinBox);
    return d->to;
}

void QQuickSpinBox::setTo(int to)
{
    Q_D(QQuickSpinBox);
    if (d->to == to)
        return;

    d->to = to;
    emit toChanged();
    if (isComponentComplete())
        setValue(d->value);
}

/*!
    \qmlproperty int QtQuick.Controls::SpinBox::value

    This property holds the value in the range \c from - \c to. The default value is \c 0.
*/
int QQuickSpinBox::value() const
{
    Q_D(const QQuickSpinBox);
    return d->value;
}

void QQuickSpinBox::setValue(int value)
{
    Q_D(QQuickSpinBox);
    if (isComponentComplete())
        value = d->boundValue(value);

    if (d->value == value)
        return;

    d->value = value;

    d->updateUpEnabled();
    d->updateDownEnabled();

    emit valueChanged();
}

/*!
    \qmlproperty int QtQuick.Controls::SpinBox::stepSize

    This property holds the step size. The default value is \c 1.

    \sa increase(), decrease()
*/
int QQuickSpinBox::stepSize() const
{
    Q_D(const QQuickSpinBox);
    return d->stepSize;
}

void QQuickSpinBox::setStepSize(int step)
{
    Q_D(QQuickSpinBox);
    if (d->stepSize == step)
        return;

    d->stepSize = step;
    emit stepSizeChanged();
}

/*!
    \qmlproperty bool QtQuick.Controls::SpinBox::editable

    This property holds whether the spinbox is editable. The default value is \c false.

    \sa validator
*/
bool QQuickSpinBox::isEditable() const
{
    Q_D(const QQuickSpinBox);
    return d->editable;
}

void QQuickSpinBox::setEditable(bool editable)
{
    Q_D(QQuickSpinBox);
    if (d->editable == editable)
        return;

    d->editable = editable;
    emit editableChanged();
}

/*!
    \qmlproperty Validator QtQuick.Controls::SpinBox::validator

    This property holds the input text validator for editable spinboxes. By
    default, SpinBox uses \l IntValidator to accept input of integer numbers.

    \snippet SpinBox.qml validator

    \sa editable, textFromValue, valueFromText, {Control::locale}{locale}
*/
QValidator *QQuickSpinBox::validator() const
{
    Q_D(const QQuickSpinBox);
    return d->validator;
}

void QQuickSpinBox::setValidator(QValidator *validator)
{
    Q_D(QQuickSpinBox);
    if (d->validator == validator)
        return;

    d->validator = validator;
    emit validatorChanged();
}

/*!
    \qmlproperty function QtQuick.Controls::SpinBox::textFromValue

    This property holds a callback function that is called whenever
    an integer value needs to be converted to display text.

    The callback function signature is \c {string function(value, locale)}.
    The function can have one or two arguments, where the first argument
    is the value to be converted, and the optional second argument is the
    locale that should be used for the conversion, if applicable.

    The default implementation does the conversion using \l {QtQml::Locale}{Number.toLocaleString()}:

    \code
    textFromValue: function(value, locale) { return Number(value).toLocaleString(locale, 'f', 0); }
    \endcode

    \sa valueFromText, validator, {Control::locale}{locale}
*/
QJSValue QQuickSpinBox::textFromValue() const
{
    Q_D(const QQuickSpinBox);
    if (!d->textFromValue.isCallable()) {
        QQmlEngine *engine = qmlEngine(this);
        if (engine)
            d->textFromValue = engine->evaluate(QStringLiteral("function(value, locale) { return Number(value).toLocaleString(locale, 'f', 0); }"));
    }
    return d->textFromValue;
}

void QQuickSpinBox::setTextFromValue(const QJSValue &callback)
{
    Q_D(QQuickSpinBox);
    if (!callback.isCallable()) {
        qmlInfo(this) << "textFromValue must be a callable function";
        return;
    }
    d->textFromValue = callback;
    emit textFromValueChanged();
}

/*!
    \qmlproperty function QtQuick.Controls::SpinBox::valueFromText

    This property holds a callback function that is called whenever
    input text needs to be converted to an integer value.

    The callback function signature is \c {int function(text, locale)}.
    The function can have one or two arguments, where the first argument
    is the text to be converted, and the optional second argument is the
    locale that should be used for the conversion, if applicable.

    The default implementation does the conversion using \l {QtQml::Locale}{Number.fromLocaleString()}:

    \code
    valueFromText: function(text, locale) { return Number.fromLocaleString(locale, text); }
    \endcode

    \sa textFromValue, validator, {Control::locale}{locale}
*/
QJSValue QQuickSpinBox::valueFromText() const
{
    Q_D(const QQuickSpinBox);
    if (!d->valueFromText.isCallable()) {
        QQmlEngine *engine = qmlEngine(this);
        if (engine)
            d->valueFromText = engine->evaluate(QStringLiteral("function(text, locale) { return Number.fromLocaleString(locale, text); }"));
    }
    return d->valueFromText;
}

void QQuickSpinBox::setValueFromText(const QJSValue &callback)
{
    Q_D(QQuickSpinBox);
    if (!callback.isCallable()) {
        qmlInfo(this) << "valueFromText must be a callable function";
        return;
    }
    d->valueFromText = callback;
    emit valueFromTextChanged();
}

/*!
    \qmlpropertygroup QtQuick.Controls::SpinBox::up
    \qmlproperty bool QtQuick.Controls::SpinBox::up.pressed
    \qmlproperty Item QtQuick.Controls::SpinBox::up.indicator

    These properties hold the up indicator item and whether it is pressed.

    \sa increase()
*/
QQuickSpinButton *QQuickSpinBox::up() const
{
    Q_D(const QQuickSpinBox);
    return d->up;
}

/*!
    \qmlpropertygroup QtQuick.Controls::SpinBox::down
    \qmlproperty bool QtQuick.Controls::SpinBox::down.pressed
    \qmlproperty Item QtQuick.Controls::SpinBox::down.indicator

    These properties hold the down indicator item and whether it is pressed.

    \sa decrease()
*/
QQuickSpinButton *QQuickSpinBox::down() const
{
    Q_D(const QQuickSpinBox);
    return d->down;
}

/*!
    \qmlmethod void QtQuick.Controls::SpinBox::increase()

    Increases the value by \l stepSize.

    \sa stepSize
*/
void QQuickSpinBox::increase()
{
    Q_D(QQuickSpinBox);
    setValue(d->value + d->effectiveStepSize());
}

/*!
    \qmlmethod void QtQuick.Controls::SpinBox::decrease()

    Decreases the value by \l stepSize.

    \sa stepSize
*/
void QQuickSpinBox::decrease()
{
    Q_D(QQuickSpinBox);
    setValue(d->value - d->effectiveStepSize());
}

void QQuickSpinBox::keyPressEvent(QKeyEvent *event)
{
    Q_D(QQuickSpinBox);
    QQuickControl::keyPressEvent(event);

    switch (event->key()) {
    case Qt::Key_Up:
        if (d->upEnabled()) {
            increase();
            d->up->setPressed(true);
            event->accept();
        }
        break;

    case Qt::Key_Down:
        if (d->downEnabled()) {
            decrease();
            d->down->setPressed(true);
            event->accept();
        }
        break;

    default:
        break;
    }

    setAccessibleProperty("pressed", d->up->isPressed() || d->down->isPressed());
}

void QQuickSpinBox::keyReleaseEvent(QKeyEvent *event)
{
    Q_D(QQuickSpinBox);
    QQuickControl::keyReleaseEvent(event);

    if (d->editable && (event->key() == Qt::Key_Enter || event->key() == Qt::Key_Return))
        d->updateValue();

    d->up->setPressed(false);
    d->down->setPressed(false);
    setAccessibleProperty("pressed", false);
}

bool QQuickSpinBox::childMouseEventFilter(QQuickItem *child, QEvent *event)
{
    Q_D(QQuickSpinBox);
    switch (event->type()) {
    case QEvent::MouseButtonPress:
        return d->handleMousePressEvent(child, static_cast<QMouseEvent *>(event));
    case QEvent::MouseMove:
        return d->handleMouseMoveEvent(child, static_cast<QMouseEvent *>(event));
    case QEvent::MouseButtonRelease:
        return d->handleMouseReleaseEvent(child, static_cast<QMouseEvent *>(event));
    case QEvent::UngrabMouse:
        return d->handleMouseUngrabEvent(child);
    default:
        return false;
    }
}

void QQuickSpinBox::mousePressEvent(QMouseEvent *event)
{
    Q_D(QQuickSpinBox);
    QQuickControl::mousePressEvent(event);
    d->handleMousePressEvent(this, event);
}

void QQuickSpinBox::mouseMoveEvent(QMouseEvent *event)
{
    Q_D(QQuickSpinBox);
    QQuickControl::mouseMoveEvent(event);
    d->handleMouseMoveEvent(this, event);
}

void QQuickSpinBox::mouseReleaseEvent(QMouseEvent *event)
{
    Q_D(QQuickSpinBox);
    QQuickControl::mouseReleaseEvent(event);
    d->handleMouseReleaseEvent(this, event);
}

void QQuickSpinBox::mouseUngrabEvent()
{
    Q_D(QQuickSpinBox);
    QQuickControl::mouseUngrabEvent();
    d->handleMouseUngrabEvent(this);
}

void QQuickSpinBox::timerEvent(QTimerEvent *event)
{
    Q_D(QQuickSpinBox);
    QQuickControl::timerEvent(event);
    if (event->timerId() == d->delayTimer) {
        d->startPressRepeat();
    } else if (event->timerId() == d->repeatTimer) {
        if (d->up->isPressed())
            increase();
        else if (d->down->isPressed())
            decrease();
    }
}

void QQuickSpinBox::wheelEvent(QWheelEvent *event)
{
    Q_D(QQuickSpinBox);
    QQuickControl::wheelEvent(event);
    if (d->wheelEnabled) {
        const int oldValue = d->value;
        const QPointF angle = event->angleDelta();
        const qreal delta = (qFuzzyIsNull(angle.y()) ? angle.x() : angle.y()) / QWheelEvent::DefaultDeltasPerStep;
        setValue(oldValue + qRound(d->effectiveStepSize() * delta));
        event->setAccepted(d->value != oldValue);
    }
}

void QQuickSpinBox::componentComplete()
{
    Q_D(QQuickSpinBox);
    QQuickControl::componentComplete();
    d->updateUpEnabled();
    d->updateDownEnabled();
}

void QQuickSpinBox::itemChange(ItemChange change, const ItemChangeData &value)
{
    Q_D(QQuickSpinBox);
    QQuickControl::itemChange(change, value);
    if (d->editable && change == ItemActiveFocusHasChanged && !value.boolValue)
        d->updateValue();
}

void QQuickSpinBox::contentItemChange(QQuickItem *newItem, QQuickItem *oldItem)
{
    Q_UNUSED(oldItem);
    if (newItem)
        newItem->setActiveFocusOnTab(true);
}

QFont QQuickSpinBox::defaultFont() const
{
    return QQuickControlPrivate::themeFont(QPlatformTheme::EditorFont);
}

#ifndef QT_NO_ACCESSIBILITY
QAccessible::Role QQuickSpinBox::accessibleRole() const
{
    return QAccessible::SpinBox;
}
#endif

class QQuickSpinButtonPrivate : public QObjectPrivate
{
public:
    QQuickSpinButtonPrivate() : pressed(false), indicator(nullptr) { }
    bool pressed;
    QQuickItem *indicator;
};

QQuickSpinButton::QQuickSpinButton(QQuickSpinBox *parent) :
    QObject(*(new QQuickSpinButtonPrivate), parent)
{
}

bool QQuickSpinButton::isPressed() const
{
    Q_D(const QQuickSpinButton);
    return d->pressed;
}

void QQuickSpinButton::setPressed(bool pressed)
{
    Q_D(QQuickSpinButton);
    if (d->pressed == pressed)
        return;

    d->pressed = pressed;
    emit pressedChanged();
}

QQuickItem *QQuickSpinButton::indicator() const
{
    Q_D(const QQuickSpinButton);
    return d->indicator;
}

void QQuickSpinButton::setIndicator(QQuickItem *indicator)
{
    Q_D(QQuickSpinButton);
    if (d->indicator == indicator)
        return;

    QQuickControl *control = qobject_cast<QQuickControl*>(d->parent);
    if (control)
        QQuickControlPrivate::get(control)->deleteDelegate(d->indicator);
    else
        delete d->indicator;

    d->indicator = indicator;

    if (indicator) {
        if (!indicator->parentItem())
            indicator->setParentItem(static_cast<QQuickItem *>(parent()));
        indicator->setAcceptedMouseButtons(Qt::LeftButton);
    }
    emit indicatorChanged();
}

QT_END_NAMESPACE