qtextbrowser.cpp

奇趣公司比较新的qt/emd版本

    This signal is emitted when the source has changed, \a src
    being the new source.

    Source changes happen both programmatically when calling
    setSource(), forward(), backword() or home() or when the user
    clicks on links or presses the equivalent key sequences.
*/

/*!  \fn void QTextBrowser::highlighted(const QUrl &link)

    This signal is emitted when the user has selected but not
    activated an anchor in the document. The URL referred to by the
    anchor is passed in \a link.
*/

/*!  \fn void QTextBrowser::highlighted(const QString &link)
     \overload

     Convenience signal that allows connecting to a slot
     that takes just a QString, like for example QStatusBar's
     message().
*/


/*!
    \fn void QTextBrowser::anchorClicked(const QUrl &link)

    This signal is emitted when the user clicks an anchor. The
    URL referred to by the anchor is passed in \a link.

    Note that the browser will automatically handle navigation to the
    location specified by \a link unless the openLinks property
    is set to false or you call setSource() in a slot connected.
    This mechanism is used to override the default navigation features of the browser.
*/

/*!
    Changes the document displayed to the previous document in the
    list of documents built by navigating links. Does nothing if there
    is no previous document.

    \sa forward(), backwardAvailable()
*/
void QTextBrowser::backward()
{
    Q_D(QTextBrowser);
    if (d->stack.count() <= 1)
        return;

    // Update the history entry
    d->forwardStack.push(d->createHistoryEntry());
    d->stack.pop(); // throw away the old version of the current entry
    d->restoreHistoryEntry(d->stack.top()); // previous entry
    emit backwardAvailable(d->stack.count() > 1);
    emit forwardAvailable(true);
}

/*!
    Changes the document displayed to the next document in the list of
    documents built by navigating links. Does nothing if there is no
    next document.

    \sa backward(), forwardAvailable()
*/
void QTextBrowser::forward()
{
    Q_D(QTextBrowser);
    if (d->forwardStack.isEmpty())
        return;
    if (!d->stack.isEmpty()) {
        // Update the history entry
        d->stack.top() = d->createHistoryEntry();
    }
    d->stack.push(d->forwardStack.pop());
    d->restoreHistoryEntry(d->stack.top());
    emit backwardAvailable(true);
    emit forwardAvailable(!d->forwardStack.isEmpty());
}

/*!
    Changes the document displayed to be the first document the
    browser displayed.
*/
void QTextBrowser::home()
{
    Q_D(QTextBrowser);
    if (d->home.isValid())
        setSource(d->home);
}

/*!
    The event \a ev is used to provide the following keyboard shortcuts:
    \table
    \header \i Keypress            \i Action
    \row \i Alt+Left Arrow  \i \l backward()
    \row \i Alt+Right Arrow \i \l forward()
    \row \i Alt+Up Arrow    \i \l home()
    \endtable
*/
void QTextBrowser::keyPressEvent(QKeyEvent *ev)
{
#ifdef QT_KEYPAD_NAVIGATION
    Q_D(QTextBrowser);
    switch (ev->key()) {
    case Qt::Key_Select:
        if (QApplication::keypadNavigationEnabled()) {
            if (!hasEditFocus()) {
                setEditFocus(true);
                return;
            } else {
                QTextCursor cursor = d->control->textCursor();
                QTextCharFormat charFmt = cursor.charFormat();
                if (!cursor.hasSelection() || charFmt.anchorHref().isEmpty()) {
                    ev->accept();
                    return;
                }
            }
        }
        break;
    case Qt::Key_Back:
        if (QApplication::keypadNavigationEnabled()) {
            if (hasEditFocus()) {
                setEditFocus(false);
                ev->accept();
                return;
            }
        }
        QTextEdit::keyPressEvent(ev);
        return;
    default:
        if (QApplication::keypadNavigationEnabled() && !hasEditFocus()) {
            ev->ignore();
            return;
        }
    }
#endif

    if (ev->modifiers() & Qt::AltModifier) {
        switch (ev->key()) {
        case Qt::Key_Right:
            forward();
            ev->accept();
            return;
        case Qt::Key_Left:
            backward();
            ev->accept();
            return;
        case Qt::Key_Up:
            home();
            ev->accept();
            return;
        }
    }
#ifdef QT_KEYPAD_NAVIGATION
    else {
        if (ev->key() == Qt::Key_Up) {
            d->keypadMove(false);
            return;
        } else if (ev->key() == Qt::Key_Down) {
            d->keypadMove(true);
            return;
        }
    }
#endif
    QTextEdit::keyPressEvent(ev);
}

/*!
    \reimp
*/
void QTextBrowser::mouseMoveEvent(QMouseEvent *e)
{
    QTextEdit::mouseMoveEvent(e);
}

/*!
    \reimp
*/
void QTextBrowser::mousePressEvent(QMouseEvent *e)
{
    QTextEdit::mousePressEvent(e);
}

/*!
    \reimp
*/
void QTextBrowser::mouseReleaseEvent(QMouseEvent *e)
{
    QTextEdit::mouseReleaseEvent(e);
}

/*!
    \reimp
*/
void QTextBrowser::focusOutEvent(QFocusEvent *ev)
{
#ifndef QT_NO_CURSOR
    Q_D(QTextBrowser);
    d->viewport->setCursor((!(d->control->textInteractionFlags() & Qt::TextEditable)) ? d->oldCursor : Qt::IBeamCursor);
#endif
    QTextEdit::focusOutEvent(ev);
}

/*!
    \reimp
*/
bool QTextBrowser::focusNextPrevChild(bool next)
{
    Q_D(QTextBrowser);
    if (d->control->setFocusToNextOrPreviousAnchor(next)) {
#ifdef QT_KEYPAD_NAVIGATION
        // Might need to synthesize a highlight event.
        if (d->prevFocus != d->control->textCursor() && d->control->textCursor().hasSelection()) {
            const QString href = d->control->anchorAtCursor();
            QUrl url = d->resolveUrl(href);
            emit highlighted(url);
            emit highlighted(url.toString());
        }
        d->prevFocus = d->control->textCursor();
#endif
        return true;
    } else {
#ifdef QT_KEYPAD_NAVIGATION
        // We assume we have no highlight now.
        emit highlighted(QUrl());
        emit highlighted(QString());
#endif
    }
    return QTextEdit::focusNextPrevChild(next);
}

/*!
  \reimp
*/
void QTextBrowser::paintEvent(QPaintEvent *e)
{
    Q_D(QTextBrowser);
    QPainter p(d->viewport);
    d->paint(&p, e);
}

/*!
    This function is called when the document is loaded. The \a type
    indicates the type of resource to be loaded. For each image in
    the document, this function is called once.

    The default implementation ignores \a type and tries to locate
    the resources by interpreting \a name as a file name. If it is
    not an absolute path it tries to find the file in the paths of
    the \l searchPaths property and in the same directory as the
    current source. On success, the result is a QVariant that stores
    a QByteArray with the contents of the file.

    If you reimplement this function, you can return other QVariant
    types. The table below shows which variant types are supported
    depending on the resource type:

    \table
    \header \i ResourceType  \i QVariant::Type
    \row    \i QTextDocument::HtmlResource  \i QString or QByteArray
    \row    \i QTextDocument::ImageResource \i QImage, QPixmap or QByteArray
    \row    \i QTextDocument::StyleSheetResource \i QString or QByteArray
    \endtable
*/
QVariant QTextBrowser::loadResource(int /*type*/, const QUrl &name)
{
    Q_D(QTextBrowser);

    QByteArray data;
    QString fileName = d->findFile(d->resolveUrl(name));
    QFile f(fileName);
    if (f.open(QFile::ReadOnly)) {
        data = f.readAll();
        f.close();
    } else {
        qWarning("QTextBrowser: Cannot open '%s' for reading", name.toString().toLocal8Bit().data());
        return QVariant();
    }

    return data;
}

/*!
    \since 4.2

    Returns true if the text browser can go backward in the document history
    using backward().

    \sa backwardAvailable(), backward()
*/
bool QTextBrowser::isBackwardAvailable() const
{
    Q_D(const QTextBrowser);
    return d->stack.count() > 1;
}

/*!
    \since 4.2

    Returns true if the text browser can go forward in the document history
    using forward().

    \sa forwardAvailable(), forward()
*/
bool QTextBrowser::isForwardAvailable() const
{
    Q_D(const QTextBrowser);
    return !d->forwardStack.isEmpty();
}

/*!
    \since 4.2

    Clears the history of visited documents and disables the forward and
    backward navigation.

    \sa backward(), forward()
*/
void QTextBrowser::clearHistory()
{
    Q_D(QTextBrowser);
    d->forwardStack.clear();
    if (!d->stack.isEmpty())
        d->stack.resize(1);
    emit forwardAvailable(false);
    emit backwardAvailable(false);
}

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

    Specifies whether QTextBrowser should automatically open links to external
    sources using QDesktopServices::openUrl() instead of emitting the
    anchorClicked signal. Links are considered external if their scheme is
    neither file or qrc.

    The default value is false.
*/
bool QTextBrowser::openExternalLinks() const
{
    Q_D(const QTextBrowser);
    return d->openExternalLinks;
}

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

/*!
   \property QTextBrowser::openLinks
   \since 4.3

   This property specifies whether QTextBrowser should automatically open links the user tries to
   activate by mouse or keyboard.

   Regardless of the value of this property the anchorClicked signal is always emitted.

   The default value is true.
*/

bool QTextBrowser::openLinks() const
{
    Q_D(const QTextBrowser);
    return d->openLinks;
}

void QTextBrowser::setOpenLinks(bool open)
{
    Q_D(QTextBrowser);
    d->openLinks = open;
}

/*! \reimp */
bool QTextBrowser::event(QEvent *e)
{
    return QTextEdit::event(e);
}

#include "moc_qtextbrowser.cpp"
#endif // QT_NO_TEXTBROWSER