qt-creator/src/libs/utils/elidinglabel.cpp

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#include "elidinglabel.h"
#include <QFontMetrics>
#include <QPainter>
#include <QStyle>

/*!
    \class Utils::ElidingLabel

    \brief The ElidingLabel class is a label suitable for displaying elided
    text.
*/

namespace Utils {

ElidingLabel::ElidingLabel(QWidget *parent)
    : QLabel(parent), m_elideMode(Qt::ElideRight)
{
    setSizePolicy(QSizePolicy(QSizePolicy::Ignored, QSizePolicy::Preferred, QSizePolicy::Label));
}

ElidingLabel::ElidingLabel(const QString &text, QWidget *parent)
    : QLabel(text, parent), m_elideMode(Qt::ElideRight)
{
    setSizePolicy(QSizePolicy(QSizePolicy::Ignored, QSizePolicy::Preferred, QSizePolicy::Label));
}

Qt::TextElideMode ElidingLabel::elideMode() const
{
    return m_elideMode;
}

void ElidingLabel::setElideMode(const Qt::TextElideMode &elideMode)
{
    m_elideMode = elideMode;
    update();
}

void ElidingLabel::paintEvent(QPaintEvent *)
{
    const int m = margin();
    QRect contents = contentsRect().adjusted(m, m, -m, -m);
    QFontMetrics fm = fontMetrics();
    QString txt = text();
    if (txt.length() > 4 && fm.horizontalAdvance(txt) > contents.width()) {
        setToolTip(txt);
        txt = fm.elidedText(txt, m_elideMode, contents.width());
    } else {
        setToolTip(QString());
    }
    int flags = QStyle::visualAlignment(layoutDirection(), alignment()) | Qt::TextSingleLine;

    QPainter painter(this);
    drawFrame(&painter);
    painter.drawText(contents, flags, txt);
}

} // namespace Utils