qlabel.cpp

奇趣公司比较新的qt/emd版本

    d->updateLabel();
}

bool QLabel::wordWrap() const
{
    Q_D(const QLabel);
    return d->align & Qt::TextWordWrap;
}

/*!
    \property QLabel::indent
    \brief the label's text indent in pixels

    If a label displays text, the indent applies to the left edge if
    alignment() is Qt::AlignLeft, to the right edge if alignment() is
    Qt::AlignRight, to the top edge if alignment() is Qt::AlignTop, and
    to to the bottom edge if alignment() is Qt::AlignBottom.

    If indent is negative, or if no indent has been set, the label
    computes the effective indent as follows: If frameWidth() is 0,
    the effective indent becomes 0. If frameWidth() is greater than 0,
    the effective indent becomes half the width of the "x" character
    of the widget's current font().

    \sa alignment, margin, frameWidth(), font()
*/

void QLabel::setIndent(int indent)
{
    Q_D(QLabel);
    d->indent = indent;
    d->updateLabel();
}

int QLabel::indent() const
{
    Q_D(const QLabel);
    return d->indent;
}


/*!
    \property QLabel::margin
    \brief the width of the margin

    The margin is the distance between the innermost pixel of the
    frame and the outermost pixel of contents.

    The default margin is 0.

    \sa indent
*/
int QLabel::margin() const
{
    Q_D(const QLabel);
    return d->margin;
}

void QLabel::setMargin(int margin)
{
    Q_D(QLabel);
    if (d->margin == margin)
        return;
    d->margin = margin;
    d->updateLabel();
}

/*!
    Returns the size that will be used if the width of the label is \a
    w. If \a w is -1, the sizeHint() is returned. If \a w is 0 minimumSizeHint() is returned
*/
QSize QLabelPrivate::sizeForWidth(int w) const
{
    Q_Q(const QLabel);
    QSize contentsMargin(leftmargin + rightmargin, topmargin + bottommargin);

    QRect br;

    int hextra = 2 * margin;
    int vextra = hextra;
    QFontMetrics fm = q->fontMetrics();

    if (pixmap)
        br = pixmap->rect();
#ifndef QT_NO_PICTURE
    else if (picture)
        br = picture->boundingRect();
#endif
#ifndef QT_NO_MOVIE
    else if (movie)
        br = movie->currentPixmap().rect();
#endif
    else if (isTextLabel) {
        int align = QStyle::visualAlignment(q->layoutDirection(), QFlag(this->align));
        // Add indentation
        int m = indent;

        if (m < 0 && q->frameWidth()) // no indent, but we do have a frame
            m = fm.width(QLatin1Char('x')) - margin*2;
        if (m > 0) {
            if ((align & Qt::AlignLeft) || (align & Qt::AlignRight))
                hextra += m;
            if ((align & Qt::AlignTop) || (align & Qt::AlignBottom))
                vextra += m;
        }

        if (control) {
            ensureTextLayouted();
            const qreal oldTextWidth = control->textWidth();
            // Calculate the length of document if w is the width
            if (align & Qt::TextWordWrap) {
                if (w >= 0) {
                    w = qMax(w-hextra-contentsMargin.width(), 0); // strip margin and indent
                    control->setTextWidth(w);
                } else {
                    control->adjustSize();
                }
            } else {
                control->setTextWidth(-1);
            }
            br = QRect(QPoint(0, 0), control->size().toSize());

            // restore state
            control->setTextWidth(oldTextWidth);
        } else {
            int flags = align;
            if (hasShortcut) {
                flags |= Qt::TextShowMnemonic;
                QStyleOption opt;
                opt.initFrom(q);
                if (!q->style()->styleHint(QStyle::SH_UnderlineShortcut, &opt, q))
                    flags |= Qt::TextHideMnemonic;
            }

            bool tryWidth = (w < 0) && (align & Qt::TextWordWrap);
            if (tryWidth)
                w = fm.averageCharWidth() * 80;
            else if (w < 0)
                w = 2000;
            w -= (hextra + contentsMargin.width());
            br = fm.boundingRect(0, 0, w ,2000, flags, text);
            if (tryWidth && br.height() < 4*fm.lineSpacing() && br.width() > w/2)
                br = fm.boundingRect(0, 0, w/2, 2000, flags, text);
            if (tryWidth && br.height() < 2*fm.lineSpacing() && br.width() > w/4)
                br = fm.boundingRect(0, 0, w/4, 2000, flags, text);
        }
    } else {
        br = QRect(QPoint(0, 0), QSize(fm.averageCharWidth(), fm.lineSpacing()));
    }

    const QSize contentsSize(br.width() + hextra, br.height() + vextra);
    return contentsSize + contentsMargin;
}


/*!
  \reimp
*/

int QLabel::heightForWidth(int w) const
{
    Q_D(const QLabel);
    if (d->isTextLabel)
        return d->sizeForWidth(w).height();
    return QWidget::heightForWidth(w);
}

/*!
    \property QLabel::openExternalLinks
    \since 4.2

    Specifies whether QLabel should automatically open links using
    QDesktopServices::openUrl() instead of emitting the
    anchorClicked() signal.

    \bold{Note:} The textInteractionFlags set on the label need to include
    either LinksAccessibleByMouse or LinksAccessibleByKeyboard.

    The default value is false.

    \sa textInteractionFlags()
*/
bool QLabel::openExternalLinks() const
{
    Q_D(const QLabel);
    return d->openExternalLinks;
}

void QLabel::setOpenExternalLinks(bool open)
{
    Q_D(QLabel);
    d->openExternalLinks = open;
    if (d->control)
        d->control->setOpenExternalLinks(open);
}

/*!
    \property QLabel::textInteractionFlags
    \since 4.2

    Specifies how the label should interact with user input if it displays text.

    If the flags contain Qt::LinksAccessibleByKeyboard the focus policy is also
    automatically set to Qt::StrongFocus. If Qt::TextSelectableByKeyboard is set
    then the focus policy is set to Qt::ClickFocus.

    The default value is Qt::LinksAccessibleByMouse.
*/
void QLabel::setTextInteractionFlags(Qt::TextInteractionFlags flags)
{
    Q_D(QLabel);
    if (d->textInteractionFlags == flags)
        return;
    d->textInteractionFlags = flags;
    if (flags & Qt::LinksAccessibleByKeyboard)
        setFocusPolicy(Qt::StrongFocus);
    else if (flags & (Qt::TextSelectableByKeyboard | Qt::TextSelectableByMouse))
        setFocusPolicy(Qt::ClickFocus);
    else
        setFocusPolicy(Qt::NoFocus);

    if (d->needTextControl()) {
        d->ensureTextControl();
    } else {
        delete d->control;
        d->control = 0;
    }

    if (d->control)
        d->control->setTextInteractionFlags(d->textInteractionFlags);
}

Qt::TextInteractionFlags QLabel::textInteractionFlags() const
{
    Q_D(const QLabel);
    return d->textInteractionFlags;
}

/*!\reimp
*/
QSize QLabel::sizeHint() const
{
    Q_D(const QLabel);
    if (!d->valid_hints)
        (void) QLabel::minimumSizeHint();
    return d->sh;
}

/*!
  \reimp
*/
QSize QLabel::minimumSizeHint() const
{
    Q_D(const QLabel);
    if (d->valid_hints) {
        if (d->sizePolicy == sizePolicy())
            return d->msh;
    }

    ensurePolished();
    d->valid_hints = true;
    d->sh = d->sizeForWidth(-1); // wrap ? golden ratio : min doc size
    QSize msh(-1, -1);

    if (!d->isTextLabel) {
        msh = d->sh;
    } else {
        msh.rheight() = d->sizeForWidth(QWIDGETSIZE_MAX).height(); // height for one line
        msh.rwidth() = d->sizeForWidth(0).width(); // wrap ? size of biggest word : min doc size
        if (d->sh.height() < msh.height())
            msh.rheight() = d->sh.height();
    }
    d->msh = msh;
    d->sizePolicy = sizePolicy();
    return msh;
}

/*!\reimp
*/
void QLabel::mousePressEvent(QMouseEvent *ev)
{
    Q_D(QLabel);
    d->sendControlEvent(ev);
}

/*!\reimp
*/
void QLabel::mouseMoveEvent(QMouseEvent *ev)
{
    Q_D(QLabel);
    d->sendControlEvent(ev);
}

/*!\reimp
*/
void QLabel::mouseReleaseEvent(QMouseEvent *ev)
{
    Q_D(QLabel);
    d->sendControlEvent(ev);
}

/*!\reimp
*/
void QLabel::contextMenuEvent(QContextMenuEvent *ev)
{
#ifdef QT_NO_CONTEXTMENU
    Q_UNUSED(ev);
#else
    Q_D(QLabel);
    if (!d->isTextLabel) {
        ev->ignore();
        return;
    }
    QMenu *menu = d->createStandardContextMenu(ev->pos());
    if (!menu) {
        ev->ignore();
        return;
    }
    ev->accept();
    menu->exec(ev->globalPos());
    delete menu;
#endif
}

/*!
    \reimp
*/
void QLabel::focusInEvent(QFocusEvent *ev)
{
    Q_D(QLabel);
    if (d->isTextLabel) {
        d->ensureTextControl();
        d->sendControlEvent(ev);
    }
    QFrame::focusInEvent(ev);
}

/*!
    \reimp
*/
void QLabel::focusOutEvent(QFocusEvent *ev)
{
    Q_D(QLabel);
    d->sendControlEvent(ev);
    QFrame::focusOutEvent(ev);
}

/*!\reimp
*/
bool QLabel::focusNextPrevChild(bool next)
{
    Q_D(QLabel);
    if (d->control && d->control->setFocusToNextOrPreviousAnchor(next))
        return true;
    return QFrame::focusNextPrevChild(next);
}

/*!\reimp
*/
void QLabel::keyPressEvent(QKeyEvent *ev)
{
    Q_D(QLabel);
    d->sendControlEvent(ev);
}

/*!\reimp
*/
bool QLabel::event(QEvent *e)
{
    Q_D(QLabel);
    QEvent::Type type = e->type();

#ifndef QT_NO_SHORTCUT
    if (type == QEvent::Shortcut) {
        QShortcutEvent *se = static_cast<QShortcutEvent *>(e);
        if (se->shortcutId() == d->shortcutId) {
            QWidget * w = d->buddy;
            QAbstractButton *button = qobject_cast<QAbstractButton *>(w);
            if (w->focusPolicy() != Qt::NoFocus)
                w->setFocus(Qt::ShortcutFocusReason);
            if (button && !se->isAmbiguous())
                button->animateClick();
            else
                window()->setAttribute(Qt::WA_KeyboardFocusChange);
            return true;
        }
    } else
#endif
    if (type == QEvent::Resize) {
        if (d->control)
            d->textLayoutDirty = true;
    } else if (e->type() == QEvent::StyleChange
#ifdef Q_WS_MAC
               || e->type() == QEvent::MacSizeChange
#endif
               ) {
        d->setLayoutItemMargins(QStyle::SE_LabelLayoutItem);
        d->updateLabel();
    }

    return QFrame::event(e);
}

/*!\reimp
*/
void QLabel::paintEvent(QPaintEvent *)
{
    Q_D(QLabel);
    QStyle *style = QWidget::style();
    QPainter painter(this);
    drawFrame(&painter);
    QRect cr = contentsRect();
    cr.adjust(d->margin, d->margin, -d->margin, -d->margin);
    int align = QStyle::visualAlignment(layoutDirection(), QFlag(d->align));

#ifndef QT_NO_MOVIE
    if (d->movie) {
        if (d->scaledcontents)
            style->drawItemPixmap(&painter, cr, align, d->movie->currentPixmap().scaled(cr.size()));
        else
            style->drawItemPixmap(&painter, cr, align, d->movie->currentPixmap());
    }
    else
#endif
    if (d->isTextLabel) {
        QRectF lr = d->layoutRect();
        if (d->control) {
#ifndef QT_NO_SHORTCUT
            const bool underline = (bool)style->styleHint(QStyle::SH_UnderlineShortcut, 0, this, 0);
            if (d->shortcutId != 0
                && underline != d->shortcutCursor.charFormat().fontUnderline()) {
                QTextCharFormat fmt;
                fmt.setFontUnderline(underline);
                d->shortcutCursor.mergeCharFormat(fmt);
            }
#endif
            d->ensureTextLayouted();

            QAbstractTextDocumentLayout::PaintContext context;
            QStyleOption opt(0);
            opt.init(this);

            if (!isEnabled() && style->styleHint(QStyle::SH_EtchDisabledText, &opt, this)) {
                context.palette = palette();
                context.palette.setColor(QPalette::Text, context.palette.light().color());
                painter.save();
                painter.translate(lr.x() + 1, lr.y() + 1);
                painter.setClipRect(lr.translated(-lr.x() - 1, -lr.y() - 1));
                QAbstractTextDocumentLayout *layout = d->control->document()->documentLayout();
                layout->draw(&painter, context);
                painter.restore();
            }

            // Adjust the palette
            context.palette = palette();
            if (foregroundRole() != QPalette::Text && isEnabled())
                context.palette.setColor(QPalette::Text, context.palette.color(foregroundRole()));

            painter.save();
            painter.translate(lr.topLeft());
            painter.setClipRect(lr.translated(-lr.x(), -lr.y()));
            d->control->setPalette(context.palette);
            d->control->drawContents(&painter, QRectF(), this);
            painter.restore();
        } else {
            int flags = align;
            if (d->hasShortcut) {
                flags |= Qt::TextShowMnemonic;
                QStyleOption opt;
                opt.initFrom(this);
                if (!style->styleHint(QStyle::SH_UnderlineShortcut, &opt, this))
                    flags |= Qt::TextHideMnemonic;
            }
            style->drawItemText(&painter, lr.toRect(), flags, palette(), isEnabled(), d->text, foregroundRole());
        }
    } else
#ifndef QT_NO_PICTURE
    if (d->picture) {
        QRect br = d->picture->boundingRect();
        int rw = br.width();
        int rh = br.height();
        if (d->scaledcontents) {
            painter.save();
            painter.translate(cr.x(), cr.y());
            painter.scale((double)cr.width()/rw, (double)cr.height()/rh);
            painter.drawPicture(-br.x(), -br.y(), *d->picture);
            painter.restore();
        } else {
            int xo = 0;
            int yo = 0;
            if (align & Qt::AlignVCenter)
                yo = (cr.height()-rh)/2;
            else if (align & Qt::AlignBottom)
                yo = cr.height()-rh;
            if (align & Qt::AlignRight)
                xo = cr.width()-rw;
            else if (align & Qt::AlignHCenter)
                xo = (cr.width()-rw)/2;
            painter.drawPicture(cr.x()+xo-br.x(), cr.y()+yo-br.y(), *d->picture);
        }
    } else
#endif
    if (d->pixmap && !d->pixmap->isNull()) {
        QPixmap pix;
        if (d->scaledcontents) {
            if (!d->scaledpixmap || d->scaledpixmap->size() != cr.size()) {
                if (!d->cachedimage)
                    d->cachedimage = new QImage(d->pixmap->toImage());
                delete d->scaledpixmap;
                d->scaledpixmap = new QPixmap(QPixmap::fromImage(d->cachedimage->scaled(cr.size(),Qt::IgnoreAspectRatio,Qt::SmoothTransformation)));
            }
            pix = *d->scaledpixmap;
        } else
            pix = *d->pixmap;
        QStyleOption opt;
        opt.initFrom(this);
        if (!isEnabled())
            pix = style->generatedIconPixmap(QIcon::Disabled, pix, &opt);
        style->drawItemPixmap(&painter, cr, align, pix);
    }
}


/*!
    Updates the label, but not the frame.
*/