QFD2/QFD/widgets/MixWithComboxInput.cpp

#include "MixWithComboxInput.h"

#include <QComboBox>
#include <QLabel>
#include <QHBoxLayout>
#include <QPainter>
#include <QAbstractItemView>
#include <QKeyEvent>

class MixWithComboxInput::Private
{
public:
    QComboBox *combo;
    QLabel *label;
    bool inside;
    bool isFlat;
};

MixWithComboxInput::MixWithComboxInput(QWidget *parent) : QStackedWidget(parent), d(new Private)
{
#ifdef Q_OS_MACOS
    setAttribute(Qt::WA_MacMiniSize, true);
#endif

    QWidget *first      = new QWidget(this);
    QHBoxLayout *layout = new QHBoxLayout(first);
    layout->setSpacing(0);
    layout->setMargin(0);
    d->label = new QLabel(first);
    d->label->setAlignment(Qt::AlignRight | Qt::AlignVCenter);
    layout->addWidget(d->label, 10);
    QLabel *icon = new QLabel(first);
    QStyleOption option;
    option.state = QStyle::State_Enabled;
    QPixmap pixmap(16, 16);
    pixmap.fill(QColor(255, 255, 255, 0));
    QPainter painter(&pixmap);
    painter.translate(8, 8);
    style()->drawPrimitive(QStyle::PE_IndicatorArrowDown, &option, &painter);
    icon->setPixmap(pixmap);
    layout->addWidget(icon);
    addWidget(first);
    d->combo = new QComboBox(this);
    d->combo->setMaxVisibleItems(15);
    d->combo->setEditable(true);
    d->combo->installEventFilter(this);
    addWidget(d->combo);
    d->inside = false;
    d->isFlat = true;

    connect(d->combo, SIGNAL(activated(QString)), this, SIGNAL(inputLevelChanged(QString)));
    connect(d->combo, SIGNAL(activated(QString)), this, SLOT(setCurrentInputLevel(QString)));
}

MixWithComboxInput::~MixWithComboxInput()
{
    delete d;
}

void MixWithComboxInput::enterEvent(QEvent *event)
{
    Q_UNUSED(event);

    d->inside = true;
    if (!isFlat()) {
        return;
    }

    if (d->combo->view()) {
        d->combo->view()->removeEventFilter(this);
    }

    setCurrentIndex(1);
}

void MixWithComboxInput::leaveEvent(QEvent *event)
{
    Q_UNUSED(event);

    d->inside = false;
    if (!isFlat()) {
        return;
    }

    if (d->combo->view() && d->combo->view()->isVisible()) {
        d->combo->view()->installEventFilter(this);
        return;
    }

    if (!d->combo->hasFocus())
        setCurrentIndex(0);
}

void MixWithComboxInput::keyPressEvent(QKeyEvent *event)
{
    if (event->key() == Qt::Key_Return || event->key() == Qt::Key_Enter) {
        focusNextChild();
    }
}

bool MixWithComboxInput::isFlat() const
{
    return d->isFlat;
}

void MixWithComboxInput::setFlat(bool flat)
{
    if (flat == d->isFlat) {
        return;
    }

    d->isFlat = flat;

    if (flat) {
        d->combo->installEventFilter(this);
        if (d->inside) {
            enterEvent(nullptr);
        } else {
            leaveEvent(nullptr);
        }
        d->combo->setEditable(true);
    } else {
        d->combo->removeEventFilter(this);
        if (d->combo->view()) {
            d->combo->view()->removeEventFilter(this);
        }
        d->combo->setCurrentIndex(d->combo->findText(d->label->text()));
        d->combo->setEditable(false);
        setCurrentIndex(1);
    }
}

void MixWithComboxInput::setInputLevels(const QStringList &levels)
{
    d->combo->clear();
    d->combo->addItems(levels);
}

void MixWithComboxInput::setCurrentInputLevel(const QString &level)
{
    d->combo->setCurrentIndex(d->combo->findText(level));
    d->label->setText(level);
}

bool MixWithComboxInput::eventFilter(QObject *watched, QEvent *event)
{
    if (watched == d->combo->view() && event->type() == QEvent::Hide) {
        focusNextChild();
        setCurrentIndex(0);
    } else if (watched == d->combo && event->type() == QEvent::FocusOut
               && (d->combo->view() && !d->combo->view()->hasFocus()) && !d->inside) {
        setCurrentIndex(0);
    }
    return false;
}