/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtGui module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
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** $QT_END_LICENSE$
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****************************************************************************/
#include "qpainter.h"
#include "qevent.h"
#include "qdrawutil.h"
#include "qapplication.h"
#include "qabstractbutton.h"
#include "qstyle.h"
#include "qstyleoption.h"
#include <limits.h>
#include "qaction.h"
#include "qclipboard.h"
#include <qdebug.h>
#include <qurl.h>
#include "qlabel_p.h"
#include "private/qstylesheetstyle_p.h"
QT_BEGIN_NAMESPACE
/*!
\class QLabel
\brief The QLabel widget provides a text or image display.
\ingroup basicwidgets
QLabel is used for displaying text or an image. No user
interaction functionality is provided. The visual appearance of
the label can be configured in various ways, and it can be used
for specifying a focus mnemonic key for another widget.
A QLabel can contain any of the following content types:
\table
\header \o Content \o Setting
\row \o Plain text
\o Pass a QString to setText().
\row \o Rich text
\o Pass a QString that contains rich text to setText().
\row \o A pixmap
\o Pass a QPixmap to setPixmap().
\row \o A movie
\o Pass a QMovie to setMovie().
\row \o A number
\o Pass an \e int or a \e double to setNum(), which converts
the number to plain text.
\row \o Nothing
\o The same as an empty plain text. This is the default. Set
by clear().
\endtable
When the content is changed using any of these functions, any
previous content is cleared.
By default, labels display \l{alignment}{left-aligned, vertically-centered}
text and images, where any tabs in the text to be displayed are
\l{Qt::TextExpandTabs}{automatically expanded}. However, the look
of a QLabel can be adjusted and fine-tuned in several ways.
The positioning of the content within the QLabel widget area can
be tuned with setAlignment() and setIndent(). Text content can
also wrap lines along word boundaries with setWordWrap(). For
example, this code sets up a sunken panel with a two-line text in
the bottom right corner (both lines being flush with the right
side of the label):
\snippet doc/src/snippets/code/src_gui_widgets_qlabel.cpp 0
The properties and functions QLabel inherits from QFrame can also
be used to specify the widget frame to be used for any given label.
A QLabel is often used as a label for an interactive widget. For
this use QLabel provides a useful mechanism for adding an
mnemonic (see QKeySequence) that will set the keyboard focus to
the other widget (called the QLabel's "buddy"). For example:
\snippet doc/src/snippets/code/src_gui_widgets_qlabel.cpp 1
In this example, keyboard focus is transferred to the label's
buddy (the QLineEdit) when the user presses Alt+P. If the buddy
was a button (inheriting from QAbstractButton), triggering the
mnemonic would emulate a button click.
\table 100%
\row
\o \inlineimage macintosh-label.png Screenshot of a Macintosh style label
\o A label shown in the \l{Macintosh Style Widget Gallery}{Macintosh widget style}.
\row
\o \inlineimage plastique-label.png Screenshot of a Plastique style label
\o A label shown in the \l{Plastique Style Widget Gallery}{Plastique widget style}.
\row
\o \inlineimage windowsxp-label.png Screenshot of a Windows XP style label
\o A label shown in the \l{Windows XP Style Widget Gallery}{Windows XP widget style}.
\endtable
\sa QLineEdit, QTextEdit, QPixmap, QMovie,
{fowler}{GUI Design Handbook: Label}
*/
#ifndef QT_NO_PICTURE
/*!
Returns the label's picture or 0 if the label doesn't have a
picture.
*/
const QPicture *QLabel::picture() const
{
Q_D(const QLabel);
return d->picture;
}
#endif
/*!
Constructs an empty label.
The \a parent and widget flag \a f, arguments are passed
to the QFrame constructor.
\sa setAlignment(), setFrameStyle(), setIndent()
*/
QLabel::QLabel(QWidget *parent, Qt::WindowFlags f)
: QFrame(*new QLabelPrivate(), parent, f)
{
Q_D(QLabel);
d->init();
}
/*!
Constructs a label that displays the text, \a text.
The \a parent and widget flag \a f, arguments are passed
to the QFrame constructor.
\sa setText(), setAlignment(), setFrameStyle(), setIndent()
*/
QLabel::QLabel(const QString &text, QWidget *parent, Qt::WindowFlags f)
: QFrame(*new QLabelPrivate(), parent, f)
{
Q_D(QLabel);
d->init();
setText(text);
}
#ifdef QT3_SUPPORT
/*! \obsolete
Constructs an empty label.
The \a parent, \a name and widget flag \a f, arguments are passed
to the QFrame constructor.
\sa setAlignment(), setFrameStyle(), setIndent()
*/
QLabel::QLabel(QWidget *parent, const char *name, Qt::WindowFlags f)
: QFrame(*new QLabelPrivate(), parent, f)
{
Q_D(QLabel);
if (name)
setObjectName(QString::fromAscii(name));
d->init();
}
/*! \obsolete
Constructs a label that displays the text, \a text.
The \a parent, \a name and widget flag \a f, arguments are passed
to the QFrame constructor.
\sa setText(), setAlignment(), setFrameStyle(), setIndent()
*/
QLabel::QLabel(const QString &text, QWidget *parent, const char *name,
Qt::WindowFlags f)
: QFrame(*new QLabelPrivate(), parent, f)
{
Q_D(QLabel);
if (name)
setObjectName(QString::fromAscii(name));
d->init();
setText(text);
}
/*! \obsolete
Constructs a label that displays the text \a text. The label has a
buddy widget, \a buddy.
If the \a text contains an underlined letter (a letter preceded by
an ampersand, \&), when the user presses Alt+ the underlined letter,
focus is passed to the buddy widget.
The \a parent, \a name and widget flag, \a f, arguments are passed
to the QFrame constructor.
\sa setText(), setBuddy(), setAlignment(), setFrameStyle(),
setIndent()
*/
QLabel::QLabel(QWidget *buddy, const QString &text,
QWidget *parent, const char *name, Qt::WindowFlags f)
: QFrame(*new QLabelPrivate(), parent, f)
{
Q_D(QLabel);
if (name)
setObjectName(QString::fromAscii(name));
d->init();
#ifndef QT_NO_SHORTCUT
setBuddy(buddy);
#endif
setText(text);
}
#endif //QT3_SUPPORT
/*!
Destroys the label.
*/
QLabel::~QLabel()
{
Q_D(QLabel);
d->clearContents();
}
void QLabelPrivate::init()
{
Q_Q(QLabel);
valid_hints = false;
margin = 0;
#ifndef QT_NO_MOVIE
movie = 0;
#endif
#ifndef QT_NO_SHORTCUT
shortcutId = 0;
#endif
pixmap = 0;
scaledpixmap = 0;
cachedimage = 0;
#ifndef QT_NO_PICTURE
picture = 0;
#endif
align = Qt::AlignLeft | Qt::AlignVCenter | Qt::TextExpandTabs;
indent = -1;
scaledcontents = false;
textLayoutDirty = false;
textDirty = false;
textformat = Qt::AutoText;
control = 0;
textInteractionFlags = Qt::LinksAccessibleByMouse;
isRichText = false;
isTextLabel = false;
q->setSizePolicy(QSizePolicy(QSizePolicy::Preferred, QSizePolicy::Preferred,
QSizePolicy::Label));
#ifndef QT_NO_CURSOR
validCursor = false;
onAnchor = false;
#endif
openExternalLinks = false;
setLayoutItemMargins(QStyle::SE_LabelLayoutItem);
}
/*!
\property QLabel::text
\brief the label's text
If no text has been set this will return an empty string. Setting
the text clears any previous content.
The text will be interpreted either as plain text or as rich
text, depending on the text format setting; see setTextFormat().
The default setting is Qt::AutoText; i.e. QLabel will try to
auto-detect the format of the text set.
If a buddy has been set, the buddy mnemonic key is updated
from the new text.
Note that QLabel is well-suited to display small rich text
documents, such as small documents that get their document
specific settings (font, text color, link color) from the label's
palette and font properties. For large documents, use QTextEdit
in read-only mode instead. QTextEdit can also provide a scroll bar
when necessary.
\note This function enables mouse tracking if \a text contains rich
text.
\sa setTextFormat(), setBuddy(), alignment
*/
void QLabel::setText(const QString &text)
{
Q_D(QLabel);
if (d->text == text)
return;
QTextControl *oldControl = d->control;
d->control = 0;
d->clearContents();
d->text = text;
d->isTextLabel = true;
d->textDirty = true;
d->isRichText = d->textformat == Qt::RichText
|| (d->textformat == Qt::AutoText && Qt::mightBeRichText(d->text));
d->control = oldControl;
if (d->needTextControl()) {
d->ensureTextControl();
} else {
delete d->control;
d->control = 0;
}
if (d->isRichText) {
setMouseTracking(true);
} else {
// Note: mouse tracking not disabled intentionally
}
#ifndef QT_NO_SHORTCUT
if (d->buddy)
d->updateShortcut();
#endif
d->updateLabel();
}
QString QLabel::text() const
{
Q_D(const QLabel);
return d->text;
}
/*!
Clears any label contents.
*/
void QLabel::clear()
{
Q_D(QLabel);
d->clearContents();
d->updateLabel();
}
/*!
\property QLabel::pixmap
\brief the label's pixmap
If no pixmap has been set this will return 0.
Setting the pixmap clears any previous content. The buddy
shortcut, if any, is disabled.
*/
void QLabel::setPixmap(const QPixmap &pixmap)
{
Q_D(QLabel);
if (!d->pixmap || d->pixmap->cacheKey() != pixmap.cacheKey()) {
d->clearContents();
d->pixmap = new QPixmap(pixmap);
}
if (d->pixmap->depth() == 1 && !d->pixmap->mask())
d->pixmap->setMask(*((QBitmap *)d->pixmap));
d->updateLabel();
}
const QPixmap *QLabel::pixmap() const
{
Q_D(const QLabel);
return d->pixmap;
}
#ifndef QT_NO_PICTURE
/*!
Sets the label contents to \a picture. Any previous content is
cleared.
The buddy shortcut, if any, is disabled.
\sa picture(), setBuddy()
*/
void QLabel::setPicture(const QPicture &picture)
{
Q_D(QLabel);
d->clearContents();
d->picture = new QPicture(picture);
d->updateLabel();
}
#endif // QT_NO_PICTURE
/*!
Sets the label contents to plain text containing the textual
representation of integer \a num. Any previous content is cleared.
Does nothing if the integer's string representation is the same as
the current contents of the label.
The buddy shortcut, if any, is disabled.
\sa setText(), QString::setNum(), setBuddy()
*/
void QLabel::setNum(int num)
{
QString str;
str.setNum(num);
setText(str);
}
/*!
\overload
Sets the label contents to plain text containing the textual
representation of double \a num. Any previous content is cleared.
Does nothing if the double's string representation is the same as
the current contents of the label.
The buddy shortcut, if any, is disabled.
\sa setText(), QString::setNum(), setBuddy()
*/
void QLabel::setNum(double num)
{
QString str;
str.setNum(num);
setText(str);
}
/*!
\property QLabel::alignment
\brief the alignment of the label's contents
By default, the contents of the label are left-aligned and vertically-centered.
\sa text
*/
void QLabel::setAlignment(Qt::Alignment alignment)
{
Q_D(QLabel);
if (alignment == (d->align & (Qt::AlignVertical_Mask|Qt::AlignHorizontal_Mask)))
return;
d->align = (d->align & ~(Qt::AlignVertical_Mask|Qt::AlignHorizontal_Mask))
| (alignment & (Qt::AlignVertical_Mask|Qt::AlignHorizontal_Mask));
d->updateLabel();
}
#ifdef QT3_SUPPORT
/*!
Use setAlignment(Qt::Alignment) instead.
If \a alignment specifies text flags as well, use setTextFormat()
to set those.
*/
void QLabel::setAlignment(int alignment)
{
Q_D(QLabel);
d->align = alignment & ~(Qt::AlignVertical_Mask|Qt::AlignHorizontal_Mask|Qt::TextWordWrap);
setAlignment(Qt::Alignment(QFlag(alignment)));
}
#endif
Qt::Alignment QLabel::alignment() const
{
Q_D(const QLabel);
return QFlag(d->align & (Qt::AlignVertical_Mask|Qt::AlignHorizontal_Mask));
}
/*!
\property QLabel::wordWrap
\brief the label's word-wrapping policy
If this property is true then label text is wrapped where
necessary at word-breaks; otherwise it is not wrapped at all.
By default, word wrap is disabled.
\sa text
*/
void QLabel::setWordWrap(bool on)
{
Q_D(QLabel);
if (on)
d->align |= Qt::TextWordWrap;
else
d->align &= ~Qt::TextWordWrap;
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().
By default, the indent is -1, meaning that an effective indent is
calculating in the manner described above.
\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);
if(q->minimumWidth() > 0)
w = qMax(w, q->minimumWidth());
QSize contentsMargin(leftmargin + rightmargin, topmargin + bottommargin);
QRect br;
int hextra = 2 * margin;
int vextra = hextra;
QFontMetrics fm = q->fontMetrics();
if (pixmap && !pixmap->isNull())
br = pixmap->rect();
#ifndef QT_NO_PICTURE
else if (picture && !picture->isNull())
br = picture->boundingRect();
#endif
#ifndef QT_NO_MOVIE
else if (movie && !movie->currentPixmap().isNull())
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 {
// Turn off center alignment in order to avoid rounding errors for centering,
// since centering involves a division by 2. At the end, all we want is the size.
int flags = align & ~(Qt::AlignVCenter | Qt::AlignHCenter);
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).expandedTo(q->minimumSize());
}
/*!
\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
linkActivated() 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);
if (d->control) {
d->sendControlEvent(ev);
QTextCursor cursor = d->control->textCursor();
Qt::FocusReason reason = ev->reason();
if (reason != Qt::ActiveWindowFocusReason
&& reason != Qt::PopupFocusReason
&& cursor.hasSelection()) {
cursor.clearSelection();
d->control->setTextCursor(cursor);
}
}
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();
QStyleOption opt;
opt.initFrom(this);
#ifndef QT_NO_STYLE_STYLESHEET
if (QStyleSheetStyle* cssStyle = qobject_cast<QStyleSheetStyle*>(style)) {
cssStyle->styleSheetPalette(this, &opt, &opt.palette);
}
#endif
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;
if (!isEnabled() && !d->control &&
// We cannot support etched for rich text controls because custom
// colors and links will override the light palette
style->styleHint(QStyle::SH_EtchDisabledText, &opt, this)) {
context.palette = opt.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 = opt.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;
if (!style->styleHint(QStyle::SH_UnderlineShortcut, &opt, this))
flags |= Qt::TextHideMnemonic;
}
style->drawItemText(&painter, lr.toRect(), flags, opt.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.
*/
void QLabelPrivate::updateLabel()
{
Q_Q(QLabel);
valid_hints = false;
if (isTextLabel) {
QSizePolicy policy = q->sizePolicy();
const bool wrap = align & Qt::TextWordWrap;
policy.setHeightForWidth(wrap);
if (policy != q->sizePolicy()) // ### should be replaced by WA_WState_OwnSizePolicy idiom
q->setSizePolicy(policy);
textLayoutDirty = true;
}
q->updateGeometry();
q->update(q->contentsRect());
}
#ifndef QT_NO_SHORTCUT
/*!
Sets this label's buddy to \a buddy.
When the user presses the shortcut key indicated by this label,
the keyboard focus is transferred to the label's buddy widget.
The buddy mechanism is only available for QLabels that contain
text in which one character is prefixed with an ampersand, '&'.
This character is set as the shortcut key. See the \l
QKeySequence::mnemonic() documentation for details (to display an
actual ampersand, use '&&').
In a dialog, you might create two data entry widgets and a label
for each, and set up the geometry layout so each label is just to
the left of its data entry widget (its "buddy"), for example:
\snippet doc/src/snippets/code/src_gui_widgets_qlabel.cpp 2
With the code above, the focus jumps to the Name field when the
user presses Alt+N, and to the Phone field when the user presses
Alt+P.
To unset a previously set buddy, call this function with \a buddy
set to 0.
\sa buddy(), setText(), QShortcut, setAlignment()
*/
void QLabel::setBuddy(QWidget *buddy)
{
Q_D(QLabel);
d->buddy = buddy;
if (d->isTextLabel) {
if (d->shortcutId)
releaseShortcut(d->shortcutId);
d->shortcutId = 0;
d->textDirty = true;
if (buddy)
d->updateShortcut(); // grab new shortcut
d->updateLabel();
}
}
/*!
Returns this label's buddy, or 0 if no buddy is currently set.
\sa setBuddy()
*/
QWidget * QLabel::buddy() const
{
Q_D(const QLabel);
return d->buddy;
}
void QLabelPrivate::updateShortcut()
{
Q_Q(QLabel);
Q_ASSERT(shortcutId == 0);
// Introduce an extra boolean to indicate the presence of a shortcut in the
// text. We cannot use the shortcutId itself because on the mac mnemonics are
// off by default, so QKeySequence::mnemonic always returns an empty sequence.
// But then we do want to hide the ampersands, so we can't use shortcutId.
hasShortcut = false;
if (control) {
ensureTextPopulated();
// Underline the first character that follows an ampersand
shortcutCursor = control->document()->find(QLatin1String("&"));
if (shortcutCursor.isNull())
return;
hasShortcut = true;
shortcutId = q->grabShortcut(QKeySequence::mnemonic(text));
shortcutCursor.deleteChar(); // remove the ampersand
shortcutCursor.movePosition(QTextCursor::NextCharacter, QTextCursor::KeepAnchor);
} else {
if (!text.contains(QLatin1Char('&')))
return;
hasShortcut = true;
shortcutId = q->grabShortcut(QKeySequence::mnemonic(text));
}
}
#endif // QT_NO_SHORTCUT
#ifndef QT_NO_MOVIE
void QLabelPrivate::_q_movieUpdated(const QRect& rect)
{
Q_Q(QLabel);
if (movie && movie->isValid()) {
QRect r;
if (scaledcontents) {
QRect cr = q->contentsRect();
QRect pixmapRect(cr.topLeft(), movie->currentPixmap().size());
if (pixmapRect.isEmpty())
return;
r.setRect(cr.left(), cr.top(),
(rect.width() * cr.width()) / pixmapRect.width(),
(rect.height() * cr.height()) / pixmapRect.height());
} else {
r = q->style()->itemPixmapRect(q->contentsRect(), align, movie->currentPixmap());
r.translate(rect.x(), rect.y());
r.setWidth(qMin(r.width(), rect.width()));
r.setHeight(qMin(r.height(), rect.height()));
}
q->update(r);
}
}
void QLabelPrivate::_q_movieResized(const QSize& size)
{
Q_Q(QLabel);
q->update(); //we need to refresh the whole background in case the new size is smaler
valid_hints = false;
_q_movieUpdated(QRect(QPoint(0,0), size));
q->updateGeometry();
}
/*!
Sets the label contents to \a movie. Any previous content is
cleared. The label does NOT take ownership of the movie.
The buddy shortcut, if any, is disabled.
\sa movie(), setBuddy()
*/
void QLabel::setMovie(QMovie *movie)
{
Q_D(QLabel);
d->clearContents();
if (!movie)
return;
d->movie = movie;
connect(movie, SIGNAL(resized(QSize)), this, SLOT(_q_movieResized(QSize)));
connect(movie, SIGNAL(updated(QRect)), this, SLOT(_q_movieUpdated(QRect)));
// Assume that if the movie is running,
// resize/update signals will come soon enough
if (movie->state() != QMovie::Running)
d->updateLabel();
}
#endif // QT_NO_MOVIE
/*!
\internal
Clears any contents, without updating/repainting the label.
*/
void QLabelPrivate::clearContents()
{
delete control;
control = 0;
isTextLabel = false;
hasShortcut = false;
#ifndef QT_NO_PICTURE
delete picture;
picture = 0;
#endif
delete scaledpixmap;
scaledpixmap = 0;
delete cachedimage;
cachedimage = 0;
delete pixmap;
pixmap = 0;
text.clear();
Q_Q(QLabel);
#ifndef QT_NO_SHORTCUT
if (shortcutId)
q->releaseShortcut(shortcutId);
shortcutId = 0;
#endif
#ifndef QT_NO_MOVIE
if (movie) {
QObject::disconnect(movie, SIGNAL(resized(QSize)), q, SLOT(_q_movieResized(QSize)));
QObject::disconnect(movie, SIGNAL(updated(QRect)), q, SLOT(_q_movieUpdated(QRect)));
}
movie = 0;
#endif
#ifndef QT_NO_CURSOR
if (onAnchor) {
if (validCursor)
q->setCursor(cursor);
else
q->unsetCursor();
}
validCursor = false;
onAnchor = false;
#endif
}
#ifndef QT_NO_MOVIE
/*!
Returns a pointer to the label's movie, or 0 if no movie has been
set.
\sa setMovie()
*/
QMovie *QLabel::movie() const
{
Q_D(const QLabel);
return d->movie;
}
#endif // QT_NO_MOVIE
/*!
\property QLabel::textFormat
\brief the label's text format
See the Qt::TextFormat enum for an explanation of the possible
options.
The default format is Qt::AutoText.
\sa text()
*/
Qt::TextFormat QLabel::textFormat() const
{
Q_D(const QLabel);
return d->textformat;
}
void QLabel::setTextFormat(Qt::TextFormat format)
{
Q_D(QLabel);
if (format != d->textformat) {
d->textformat = format;
QString t = d->text;
if (!t.isNull()) {
d->text.clear();
setText(t);
}
}
}
/*!
\reimp
*/
void QLabel::changeEvent(QEvent *ev)
{
Q_D(QLabel);
if(ev->type() == QEvent::FontChange || ev->type() == QEvent::ApplicationFontChange) {
if (d->isTextLabel) {
if (d->control)
d->control->document()->setDefaultFont(font());
d->updateLabel();
}
} else if (ev->type() == QEvent::PaletteChange && d->control) {
d->control->setPalette(palette());
} else if (ev->type() == QEvent::ContentsRectChange) {
d->updateLabel();
} else if (ev->type() == QEvent::LayoutDirectionChange) {
if (d->isTextLabel && d->control) {
d->sendControlEvent(ev);
}
}
QFrame::changeEvent(ev);
}
/*!
\property QLabel::scaledContents
\brief whether the label will scale its contents to fill all
available space.
When enabled and the label shows a pixmap, it will scale the
pixmap to fill the available space.
This property's default is false.
*/
bool QLabel::hasScaledContents() const
{
Q_D(const QLabel);
return d->scaledcontents;
}
void QLabel::setScaledContents(bool enable)
{
Q_D(QLabel);
if ((bool)d->scaledcontents == enable)
return;
d->scaledcontents = enable;
if (!enable) {
delete d->scaledpixmap;
d->scaledpixmap = 0;
delete d->cachedimage;
d->cachedimage = 0;
}
update(contentsRect());
}
/*!
\fn void QLabel::setAlignment(Qt::AlignmentFlag flag)
\internal
Without this function, a call to e.g. setAlignment(Qt::AlignTop)
results in the \c QT3_SUPPORT function setAlignment(int) being called,
rather than setAlignment(Qt::Alignment).
*/
// Returns the rect that is available for us to draw the document
QRect QLabelPrivate::documentRect() const
{
Q_Q(const QLabel);
Q_ASSERT_X(isTextLabel, "documentRect", "document rect called for label that is not a text label!");
QRect cr = q->contentsRect();
cr.adjust(margin, margin, -margin, -margin);
const int align = QStyle::visualAlignment(q->layoutDirection(), QFlag(this->align));
int m = indent;
if (m < 0 && q->frameWidth()) // no indent, but we do have a frame
m = q->fontMetrics().width(QLatin1Char('x')) / 2 - margin;
if (m > 0) {
if (align & Qt::AlignLeft)
cr.setLeft(cr.left() + m);
if (align & Qt::AlignRight)
cr.setRight(cr.right() - m);
if (align & Qt::AlignTop)
cr.setTop(cr.top() + m);
if (align & Qt::AlignBottom)
cr.setBottom(cr.bottom() - m);
}
return cr;
}
void QLabelPrivate::ensureTextPopulated() const
{
if (!textDirty)
return;
if (control) {
QTextDocument *doc = control->document();
if (textDirty) {
#ifndef QT_NO_TEXTHTMLPARSER
if (isRichText)
doc->setHtml(text);
else
doc->setPlainText(text);
#else
doc->setPlainText(text);
#endif
doc->setUndoRedoEnabled(false);
}
}
textDirty = false;
}
void QLabelPrivate::ensureTextLayouted() const
{
if (!textLayoutDirty)
return;
ensureTextPopulated();
Q_Q(const QLabel);
if (control) {
QTextDocument *doc = control->document();
QTextOption opt = doc->defaultTextOption();
opt.setAlignment(QFlag(this->align));
if (this->align & Qt::TextWordWrap)
opt.setWrapMode(QTextOption::WordWrap);
else
opt.setWrapMode(QTextOption::ManualWrap);
opt.setTextDirection(q->layoutDirection());
doc->setDefaultTextOption(opt);
QTextFrameFormat fmt = doc->rootFrame()->frameFormat();
fmt.setMargin(0);
doc->rootFrame()->setFrameFormat(fmt);
doc->setTextWidth(documentRect().width());
}
textLayoutDirty = false;
}
void QLabelPrivate::ensureTextControl() const
{
Q_Q(const QLabel);
if (!isTextLabel)
return;
if (!control) {
control = new QTextControl(const_cast<QLabel *>(q));
control->document()->setUndoRedoEnabled(false);
control->document()->setDefaultFont(q->font());
control->setTextInteractionFlags(textInteractionFlags);
control->setOpenExternalLinks(openExternalLinks);
control->setPalette(q->palette());
control->setFocus(q->hasFocus());
QObject::connect(control, SIGNAL(updateRequest(QRectF)),
q, SLOT(update()));
QObject::connect(control, SIGNAL(linkHovered(QString)),
q, SLOT(_q_linkHovered(QString)));
QObject::connect(control, SIGNAL(linkActivated(QString)),
q, SIGNAL(linkActivated(QString)));
textLayoutDirty = true;
textDirty = true;
}
}
void QLabelPrivate::sendControlEvent(QEvent *e)
{
Q_Q(QLabel);
if (!isTextLabel || !control || textInteractionFlags == Qt::NoTextInteraction) {
e->ignore();
return;
}
control->processEvent(e, -layoutRect().topLeft(), q);
}
void QLabelPrivate::_q_linkHovered(const QString &anchor)
{
Q_Q(QLabel);
#ifndef QT_NO_CURSOR
if (anchor.isEmpty()) { // restore cursor
if (validCursor)
q->setCursor(cursor);
else
q->unsetCursor();
onAnchor = false;
} else if (!onAnchor) {
validCursor = q->testAttribute(Qt::WA_SetCursor);
if (validCursor) {
cursor = q->cursor();
}
q->setCursor(Qt::PointingHandCursor);
onAnchor = true;
}
#endif
emit q->linkHovered(anchor);
}
// Return the layout rect - this is the rect that is given to the layout painting code
// This may be different from the document rect since vertical alignment is not
// done by the text layout code
QRectF QLabelPrivate::layoutRect() const
{
QRectF cr = documentRect();
if (!control)
return cr;
ensureTextLayouted();
// Caculate y position manually
qreal rh = control->document()->documentLayout()->documentSize().height();
qreal yo = 0;
if (align & Qt::AlignVCenter)
yo = qMax((cr.height()-rh)/2, qreal(0));
else if (align & Qt::AlignBottom)
yo = qMax(cr.height()-rh, qreal(0));
return QRectF(cr.x(), yo + cr.y(), cr.width(), cr.height());
}
// Returns the point in the document rect adjusted with p
QPoint QLabelPrivate::layoutPoint(const QPoint& p) const
{
QRect lr = layoutRect().toRect();
return p - lr.topLeft();
}
#ifndef QT_NO_CONTEXTMENU
QMenu *QLabelPrivate::createStandardContextMenu(const QPoint &pos)
{
QString linkToCopy;
QPoint p;
if (control && isRichText) {
p = layoutPoint(pos);
linkToCopy = control->document()->documentLayout()->anchorAt(p);
}
if (linkToCopy.isEmpty() && !control)
return 0;
return control->createStandardContextMenu(p, q_func());
}
#endif
/*!
\fn void QLabel::linkHovered(const QString &link)
\since 4.2
This signal is emitted when the user hovers over a link. The URL
referred to by the anchor is passed in \a link.
\sa linkActivated()
*/
/*!
\fn void QLabel::linkActivated(const QString &link)
\since 4.2
This signal is emitted when the user clicks a link. The URL
referred to by the anchor is passed in \a link.
\sa linkHovered()
*/
QT_END_NAMESPACE
#include "moc_qlabel.cpp"