C++ QwtDynGridLayout类代码示例

/*!
  \brief Set the maximum number of entries in a row

  F.e when the maximum is set to 1 all items are aligned
  vertically. 0 means unlimited

  \param numColums Maximum number of entries in a row

  \sa maxColumns(), QwtDynGridLayout::setMaxColumns()
 */
void QwtLegend::setMaxColumns( uint numColums )
{
    QwtDynGridLayout *tl = qobject_cast<QwtDynGridLayout *>(
        d_data->view->contentsWidget->layout() );
    if ( tl )
        tl->setMaxColumns( numColums );
}

/*!
  Print the legend into a given rectangle.

  \param plot Plot widget
  \param painter Painter
  \param rect Bounding rectangle
*/
void QwtPlotRenderer::renderLegend( const QwtPlot *plot,
    QPainter *painter, const QRectF &rect ) const
{
    if ( !plot->legend() || plot->legend()->isEmpty() )
        return;

    QLayout *l = plot->legend()->contentsWidget()->layout();
    if ( l == 0 || !l->inherits( "QwtDynGridLayout" ) )
        return;

    QwtDynGridLayout *legendLayout = ( QwtDynGridLayout * )l;

    uint numCols = legendLayout->columnsForWidth( rect.width() );
    QList<QRect> itemRects =
        legendLayout->layoutItems( rect.toRect(), numCols );

    int index = 0;

    for ( int i = 0; i < legendLayout->count(); i++ )
    {
        QLayoutItem *item = legendLayout->itemAt( i );
        QWidget *w = item->widget();
        if ( w )
        {
            painter->save();

            painter->setClipRect( itemRects[index] );
            renderLegendItem( plot, painter, w, itemRects[index] );

            index++;
            painter->restore();
        }
    }
}

void QwtPlot::printLegend(QPainter *painter, const QRect &rect) const
{
    if ( !d_legend || d_legend->isEmpty() )
        return;

    QLayout *l = d_legend->contentsWidget()->layout();
    if ( l == 0 || !l->inherits("QwtDynGridLayout") )
        return;

    QwtDynGridLayout *legendLayout = (QwtDynGridLayout *)l;

    uint numCols = legendLayout->columnsForWidth(rect.width());
    QValueList<QRect> itemRects = 
        legendLayout->layoutItems(rect, numCols);

    int index = 0;

    QLayoutIterator layoutIterator = legendLayout->iterator();
    for ( QLayoutItem *item = layoutIterator.current(); 
        item != 0; item = ++layoutIterator)
    {
        QWidget *w = item->widget();
        if ( w )
        {
            painter->save();
            painter->setClipping(TRUE);
            QwtPainter::setClipRect(painter, itemRects[index]);

            printLegendItem(painter, w, itemRects[index]);

            index++;
            painter->restore();
        }
    }
}

/*!
  \brief Insert a legend

  If the position legend is \c QwtPlot::LeftLegend or \c QwtPlot::RightLegend
  the legend will be organized in one column from top to down. 
  Otherwise the legend items will be placed in a table 
  with a best fit number of columns from left to right.

  If pos != QwtPlot::ExternalLegend the plot widget will become 
  parent of the legend. It will be deleted when the plot is deleted, 
  or another legend is set with insertLegend().
       
  \param legend Legend
  \param pos The legend's position. For top/left position the number
             of colums will be limited to 1, otherwise it will be set to
             unlimited. 

  \param ratio Ratio between legend and the bounding rect
               of title, canvas and axes. The legend will be shrinked
               if it would need more space than the given ratio.
               The ratio is limited to ]0.0 .. 1.0]. In case of <= 0.0
               it will be reset to the default ratio.
               The default vertical/horizontal ratio is 0.33/0.5.

  \sa legend(), QwtPlotLayout::legendPosition(), 
      QwtPlotLayout::setLegendPosition()
*/
void QwtPlot::insertLegend(QwtLegend *legend, 
    QwtPlot::LegendPosition pos, double ratio)
{
    d_data->layout->setLegendPosition(pos, ratio);

    if ( legend != d_data->legend )
    {
        if ( d_data->legend && d_data->legend->parent() == this )
            delete d_data->legend;

        d_data->legend = legend;

        if ( d_data->legend )
        {
            if ( pos != ExternalLegend )
            {
                if ( d_data->legend->parent() != this )
                {
#if QT_VERSION < 0x040000
                    d_data->legend->reparent(this, QPoint(0, 0));
#else
                    d_data->legend->setParent(this);
#endif
                }
            }

            const QwtPlotItemList& itmList = itemList();
            for ( QwtPlotItemIterator it = itmList.begin();
                it != itmList.end(); ++it )
            {
                (*it)->updateLegend(d_data->legend);
            }

            QLayout *l = d_data->legend->contentsWidget()->layout();
            if ( l && l->inherits("QwtDynGridLayout") )
            {
                QwtDynGridLayout *tl = (QwtDynGridLayout *)l;
                switch(d_data->layout->legendPosition())
                {
                    case LeftLegend:
                    case RightLegend:
                        tl->setMaxCols(1); // 1 column: align vertical
                        break;
                    case TopLegend:
                    case BottomLegend:
                        tl->setMaxCols(0); // unlimited
                        break;
                    case ExternalLegend:
                        break;
                }
            }
        }
        updateTabOrder();
    }

    updateLayout();
}

/*!
  \brief Insert a legend

  If the position legend is \c QwtPlot::LeftLegend or \c QwtPlot::RightLegend
  the legend will be organized in one column from top to down.
  Otherwise the legend items will be placed in a table
  with a best fit number of columns from left to right.

  If pos != QwtPlot::ExternalLegend the plot widget will become
  parent of the legend. It will be deleted when the plot is deleted,
  or another legend is set with insertLegend().

  \param legend Legend
  \param pos The legend's position. For top/left position the number
             of colums will be limited to 1, otherwise it will be set to
             unlimited.

  \param ratio Ratio between legend and the bounding rect
               of title, canvas and axes. The legend will be shrinked
               if it would need more space than the given ratio.
               The ratio is limited to ]0.0 .. 1.0]. In case of <= 0.0
               it will be reset to the default ratio.
               The default vertical/horizontal ratio is 0.33/0.5.

  \sa legend(), QwtPlotLayout::legendPosition(),
      QwtPlotLayout::setLegendPosition()
*/
void QwtPlot::insertLegend( QwtLegend *legend,
    QwtPlot::LegendPosition pos, double ratio )
{
    d_data->layout->setLegendPosition( pos, ratio );

    if ( legend != d_data->legend )
    {
        if ( d_data->legend && d_data->legend->parent() == this )
            delete d_data->legend;

        d_data->legend = legend;

        if ( d_data->legend )
        {
            if ( pos != ExternalLegend )
            {
                if ( d_data->legend->parent() != this )
                    d_data->legend->setParent( this );
            }

            const QwtPlotItemList& itmList = itemList();
            for ( QwtPlotItemIterator it = itmList.begin();
                it != itmList.end(); ++it )
            {
                ( *it )->updateLegend( d_data->legend );
            }

            QwtDynGridLayout *tl = qobject_cast<QwtDynGridLayout *>(
                d_data->legend->contentsWidget()->layout() );
            if ( tl )
            {
                switch ( d_data->layout->legendPosition() )
                {
                    case LeftLegend:
                    case RightLegend:
                        tl->setMaxCols( 1 ); // 1 column: align vertical
                        break;
                    case TopLegend:
                    case BottomLegend:
                        tl->setMaxCols( 0 ); // unlimited
                        break;
                    case ExternalLegend:
                        break;
                }
            }
        }
        updateTabOrder();
    }

    updateLayout();
}

/*!
  Constructor
  \param parent Parent widget
*/
QwtLegend::QwtLegend( QWidget *parent ):
    QwtAbstractLegend( parent )
{
    setFrameStyle( NoFrame );

    d_data = new QwtLegend::PrivateData;

    d_data->view = new QwtLegend::PrivateData::LegendView( this );
    d_data->view->setObjectName( "QwtLegendView" );
    d_data->view->setFrameStyle( NoFrame );

    QwtDynGridLayout *gridLayout = new QwtDynGridLayout(
        d_data->view->contentsWidget );
    gridLayout->setAlignment( Qt::AlignHCenter | Qt::AlignTop );

    d_data->view->contentsWidget->installEventFilter( this );

    QVBoxLayout *layout = new QVBoxLayout( this );
    layout->setContentsMargins( 0, 0, 0, 0 );
    layout->addWidget( d_data->view );
}

/*!
  \param parent Parent widget
*/
QwtLegend::QwtLegend(QWidget *parent): 
    QFrame(parent)
{
    setFrameStyle(NoFrame);

    d_data = new QwtLegend::PrivateData;
    d_data->itemMode = QwtLegend::ReadOnlyItem;
    d_data->displayPolicy = QwtLegend::Auto;
    d_data->identifierMode = QwtLegendItem::ShowLine | 
        QwtLegendItem::ShowSymbol | QwtLegendItem::ShowText;

    d_data->view = new QwtLegend::PrivateData::LegendView(this);
    d_data->view->setFrameStyle(NoFrame);

    QwtDynGridLayout *layout = new QwtDynGridLayout(
        d_data->view->contentsWidget);
#if QT_VERSION < 0x040000
    layout->setAutoAdd(true);
#endif
    layout->setAlignment(Qt::AlignHCenter | Qt::AlignTop);

    d_data->view->contentsWidget->installEventFilter(this);
}

/*!
  Specify the position of the legend within the widget.
  If the position legend is \c QwtPlot::Left or \c QwtPlot::Right
  the legend will be organized in one column from top to down. 
  Otherwise the legend items will be placed be placed in a table 
  with a best fit number of columns from left to right.
       
  \param pos The legend's position. Valid values are \c QwtPlot::Left,
           \c QwtPlot::Right, \c QwtPlot::Top, \c QwtPlot::Bottom.
  \param ratio Ratio between legend and the bounding rect
               of title, canvas and axes. The legend will be shrinked
               if it would need more space than the given ratio.
               The ratio is limited to ]0.0 .. 1.0]. In case of <= 0.0
               it will be reset to the default ratio.
               The default vertical/horizontal ratio is 0.33/0.5.

  \sa QwtPlot::legendPosition(), QwtPlotLayout::setLegendPosition()
*/
void QwtPlot::setLegendPosition(QwtPlot::Position pos, double ratio)
{
    if (pos != d_layout->legendPosition())
    {
        d_layout->setLegendPosition(pos, ratio);

        QLayout *l = d_legend->contentsWidget()->layout();
        if ( l && l->inherits("QwtDynGridLayout") )
        {
            QwtDynGridLayout *tl = (QwtDynGridLayout *)l;
            if ( d_layout->legendPosition() == QwtPlot::Top ||
                d_layout->legendPosition() == QwtPlot::Bottom )
            {
                tl->setMaxCols(0); // unlimited
            }
            else
                tl->setMaxCols(1); // 1 column: align vertical
        }

        updateLayout();
        updateTabOrder();
    }
}

void QwtPlot::printLegend(QPainter *painter, const QRect &rect) const
{
    if ( !legend() || legend()->isEmpty() )
        return;

    QLayout *l = legend()->contentsWidget()->layout();
    if ( l == 0 || !l->inherits("QwtDynGridLayout") )
        return;

    QwtDynGridLayout *legendLayout = (QwtDynGridLayout *)l;

    uint numCols = legendLayout->columnsForWidth(rect.width());
#if QT_VERSION < 0x040000
    QValueList<QRect> itemRects =
        legendLayout->layoutItems(rect, numCols);
#else
    QList<QRect> itemRects =
        legendLayout->layoutItems(rect, numCols);
#endif

    int index = 0;

#if QT_VERSION < 0x040000
    QLayoutIterator layoutIterator = legendLayout->iterator();
    for ( QLayoutItem *item = layoutIterator.current();
            item != 0; item = ++layoutIterator) {
#else
    for ( int i = 0; i < legendLayout->count(); i++ ) {
        QLayoutItem *item = legendLayout->itemAt(i);
#endif
        QWidget *w = item->widget();
        if ( w ) {
            painter->save();
            painter->setClipping(true);
            QwtPainter::setClipRect(painter, itemRects[index]);

            printLegendItem(painter, w, itemRects[index]);

            index++;
            painter->restore();
        }
    }
}

/*!
  Print the legend item into a given rectangle.

  \param painter Painter
  \param w Widget representing a legend item
  \param rect Bounding rectangle
*/

void QwtPlot::printLegendItem(QPainter *painter,
                              const QWidget *w, const QRect &rect) const
{
    if ( w->inherits("QwtLegendItem") ) {
        QwtLegendItem *item = (QwtLegendItem *)w;

        painter->setFont(item->font());
        item->drawItem(painter, rect);
    }
}

/*!
  \brief Paint a scale into a given rectangle.
  Paint the scale into a given rectangle.

  \param painter Painter
  \param axisId Axis
  \param startDist Start border distance
  \param endDist End border distance
  \param baseDist Base distance
  \param rect Bounding rectangle
*/

void QwtPlot::printScale(QPainter *painter,
                         int axisId, int startDist, int endDist, int baseDist,
                         const QRect &rect) const
{
    if (!axisEnabled(axisId))
        return;

    const QwtScaleWidget *scaleWidget = axisWidget(axisId);
    if ( scaleWidget->isColorBarEnabled()
            && scaleWidget->colorBarWidth() > 0) {
        const QwtMetricsMap map = QwtPainter::metricsMap();

        QRect r = map.layoutToScreen(rect);
        r.setWidth(r.width() - 1);
        r.setHeight(r.height() - 1);

        scaleWidget->drawColorBar(painter, scaleWidget->colorBarRect(r));

        const int off = scaleWidget->colorBarWidth() + scaleWidget->spacing();
        if ( scaleWidget->scaleDraw()->orientation() == Qt::Horizontal )
            baseDist += map.screenToLayoutY(off);
        else
            baseDist += map.screenToLayoutX(off);
    }

//.........这里部分代码省略.........

void QwtPolarPlot::renderLegend( QPainter *painter, const QRect &rect ) const
{
#if 1
  // Shift this code into QwtLegend, so that Qwt/QwtPolar can share it
#endif

  if ( !legend() || legend()->isEmpty() )
    return;

  QLayout *l = legend()->contentsWidget()->layout();
  if ( l == 0 || !l->inherits( "QwtDynGridLayout" ) )
    return;

  QwtDynGridLayout *legendLayout = ( QwtDynGridLayout * )l;

  uint numCols = legendLayout->columnsForWidth( rect.width() );
#if QT_VERSION < 0x040000
  QValueList<QRect> itemRects =
    legendLayout->layoutItems( rect, numCols );
#else
  QList<QRect> itemRects =
    legendLayout->layoutItems( rect, numCols );
#endif

  int index = 0;

#if QT_VERSION < 0x040000
  QLayoutIterator layoutIterator = legendLayout->iterator();
  for ( QLayoutItem *item = layoutIterator.current();
        item != 0; item = ++layoutIterator )
  {
#else
  for ( int i = 0; i < legendLayout->count(); i++ )
  {
    QLayoutItem *item = legendLayout->itemAt( i );
#endif
    QWidget *w = item->widget();
    if ( w )
    {
      painter->save();
      painter->setClipping( true );
      QwtPainter::setClipRect( painter, itemRects[index] );

      renderLegendItem( painter, w, itemRects[index] );

      index++;
      painter->restore();
    }
  }
}

/*!
  Render the legend item into a given rectangle.

  \param painter Painter
  \param w Widget representing a legend item
  \param rect Bounding rectangle
*/

void QwtPolarPlot::renderLegendItem( QPainter *painter,
                                     const QWidget *w, const QRect &rect ) const
{
#if 1
  // Shift this code into QwtLegend, so that Qwt/QwtPolar can share it
#endif
  if ( w->inherits( "QwtLegendItem" ) )
  {
    QwtLegendItem *item = ( QwtLegendItem * )w;

    painter->setFont( item->font() );
    item->drawItem( painter, rect );
  }
}

void QwtPlot::printLegend(QPainter *painter, const QRect &rect) const
{
    if ( !legend() || legend()->isEmpty() )
        return;

    QLayout *l = legend()->contentsWidget()->layout();
    if ( l == 0 || !l->inherits("QwtDynGridLayout") )
        return;

    QwtDynGridLayout *legendLayout = (QwtDynGridLayout *)l;

    uint numCols = legendLayout->columnsForWidth(rect.width());
#if QT_VERSION < 0x040000
    QValueList<QRect> itemRects = 
        legendLayout->layoutItems(rect, numCols);
#else
    QList<QRect> itemRects = 
        legendLayout->layoutItems(rect, numCols);
#endif

    int index = 0;

#if QT_VERSION < 0x040000
    QLayoutIterator layoutIterator = legendLayout->iterator();
    for ( QLayoutItem *item = layoutIterator.current(); 
        item != 0; item = ++layoutIterator)
    {
#else
    for ( int i = 0; i < legendLayout->count(); i++ )
    {
        QLayoutItem *item = legendLayout->itemAt(i);
#endif
        QWidget *w = item->widget();
        if ( w )
        {
            painter->save();
            painter->setClipping(true);
            QwtPainter::setClipRect(painter, itemRects[index]);

            printLegendItem(painter, w, itemRects[index]);

            index++;
            painter->restore();
        }
    }
}

/*!
  Print the legend item into a given rectangle.

  \param painter Painter
  \param w Widget representing a legend item
  \param rect Bounding rectangle
*/

void QwtPlot::printLegendItem(QPainter *painter, 
    const QWidget *w, const QRect &rect) const
{
    if ( w->inherits("QwtLegendItem") )
    {
        QwtLegendItem *item = (QwtLegendItem *)w;

        painter->setFont(item->font());
        item->drawItem(painter, rect);
    }
}

/*!
  \brief Paint a scale into a given rectangle.
  Paint the scale into a given rectangle.

  \param painter Painter
  \param axisId Axis
  \param startDist Start border distance
  \param endDist End border distance
  \param baseDist Base distance
  \param rect Bounding rectangle
*/

void QwtPlot::printScale(QPainter *painter,
    int axisId, int startDist, int endDist, int baseDist, 
    const QRect &rect) const
{
    if (!axisEnabled(axisId))
        return;

    QwtScaleDraw::Alignment align;
    int x, y, w;

    switch(axisId)
    {
        case yLeft:
        {
            x = rect.right() - baseDist + 1;
            y = rect.y() + startDist;
            w = rect.height() - startDist - endDist;
            align = QwtScaleDraw::LeftScale;
            break;
        }
        case yRight:
//.........这里部分代码省略.........