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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"

#include <qmath.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.