C++ QScrollBar::height方法代码示例

bool VMdEditor::isBlockVisible(const QTextBlock &p_block)
{
    if (!p_block.isValid() || !p_block.isVisible()) {
        return false;
    }

    QScrollBar *vbar = verticalScrollBar();
    if (!vbar || !vbar->isVisible()) {
        // No vertical scrollbar.
        return true;
    }

    int height = rect().height();
    QScrollBar *hbar = horizontalScrollBar();
    if (hbar && hbar->isVisible()) {
        height -= hbar->height();
    }

    QAbstractTextDocumentLayout *layout = document()->documentLayout();
    QRectF rect = layout->blockBoundingRect(p_block);
    int y = GETVISUALOFFSETY;
    int rectHeight = (int)rect.height();

    return (y >= 0 && y < height) || (y < 0 && y + rectHeight > 0);
}

void pTreeComboBox::calculPopupGeometry()
{
    if ( !mView ) {
        return;
    }
    
    QStyle * const style = this->style();

    // set current item and select it
    view()->selectionModel()->setCurrentIndex( mCurrentIndex, QItemSelectionModel::ClearAndSelect | QItemSelectionModel::Rows );
    QFrame* container = mFrame;
    QStyleOptionComboBox opt;
    initStyleOption( &opt );
    QRect listRect( style->subControlRect( QStyle::CC_ComboBox, &opt, QStyle::SC_ComboBoxListBoxPopup, this ) );
    QRect screen = popupGeometry( QApplication::desktop()->screenNumber( this ) );
    QPoint below = mapToGlobal( listRect.bottomLeft() );
    int belowHeight = screen.bottom() -below.y();
    QPoint above = mapToGlobal( listRect.topLeft() );
    int aboveHeight = above.y() -screen.y();
    bool boundToScreen = !window()->testAttribute( Qt::WA_DontShowOnScreen );
    
    listRect.moveTopLeft( mapToGlobal( rect().bottomLeft() ) );
    listRect.setSize( QSize( 
        qMax( qMax( view()->viewport()->width(), mFrame->width() ), width() )
        ,
        qMax( view()->viewport()->height(), mFrame->height() )
    ) );

    const bool usePopup = style->styleHint( QStyle::SH_ComboBox_Popup, &opt, this );
    {
        int listHeight = 0;
        int count = 0;
        QStack<QModelIndex> toCheck;
        toCheck.push( view()->rootIndex() );
#ifndef QT_NO_TREEVIEW
        QTreeView* treeView = qobject_cast<QTreeView*>( view() );
        if ( treeView && treeView->header() && !treeView->header()->isHidden() )
            listHeight += treeView->header()->height();
#endif
        while ( !toCheck.isEmpty() ) {
            QModelIndex parent = toCheck.pop();
            for ( int i = 0; i < model()->rowCount( parent ); ++i ) {
                QModelIndex idx = model()->index( i, mModelColumn, parent );
                if ( !idx.isValid() )
                    continue;
                listHeight += view()->visualRect( idx ).height();
#ifndef QT_NO_TREEVIEW
                if ( model()->hasChildren( idx ) && treeView && treeView->isExpanded( idx ) )
                    toCheck.push( idx );
#endif
                ++count;
                if ( !usePopup && count > mMaxVisibleItems ) {
                    toCheck.clear();
                    break;
                }
            }
        }
        listRect.setHeight( listHeight );
    }

    {
        // add the spacing for the grid on the top and the bottom;
        int heightMargin = 0;

        // add the frame of the container
        int marginTop, marginBottom;
        container->getContentsMargins( 0, &marginTop, 0, &marginBottom );
        heightMargin += marginTop +marginBottom;

        //add the frame of the view
        view()->getContentsMargins( 0, &marginTop, 0, &marginBottom );
        marginTop += 0/*static_cast<QAbstractScrollAreaPrivate *>(QObjectPrivate::get(view()))->top*/;
        marginBottom += 0/*static_cast<QAbstractScrollAreaPrivate *>(QObjectPrivate::get(view()))->bottom*/;
        heightMargin += marginTop +marginBottom;

        listRect.setHeight( listRect.height() +heightMargin );
    }

    // Add space for margin at top and bottom if the style wants it.
    if ( usePopup )
        listRect.setHeight( listRect.height() +style->pixelMetric( QStyle::PM_MenuVMargin, &opt, this ) *2 );

    // Make sure the popup is wide enough to display its contents.
    if ( usePopup ) {
        const int diff = sizeHint().width() /*d->computeWidthHint()*/ -width();
        if ( diff > 0 )
            listRect.setWidth( listRect.width() +diff );
    }

    //we need to activate the layout to make sure the min/maximum size are set when the widget was not yet show
    container->layout()->activate();
    //takes account of the minimum/maximum size of the container
    listRect.setSize( listRect.size().expandedTo(container->minimumSize())
                      .boundedTo(container->maximumSize()));

    // make sure the widget fits on screen
    if (boundToScreen) {
        if (listRect.width() > screen.width() )
            listRect.setWidth(screen.width());
        if (/*mapToGlobal(*/listRect/*.bottomRight())*/.x() > screen.right()) {
//.........这里部分代码省略.........

// -------------------------------------------------------------------------
void ctkTreeComboBox::resizePopup()
{
  // copied from QComboBox.cpp
  Q_D(ctkTreeComboBox);

  QStyle * const style = this->style();
  QWidget* container = qobject_cast<QWidget*>(this->view()->parent());

  QStyleOptionComboBox opt;
  this->initStyleOption(&opt);
  QRect listRect(style->subControlRect(QStyle::CC_ComboBox, &opt,
                                       QStyle::SC_ComboBoxListBoxPopup, this));
  QRect screen = QApplication::desktop()->availableGeometry(
    QApplication::desktop()->screenNumber(this));
  QPoint below = this->mapToGlobal(listRect.bottomLeft());
  int belowHeight = screen.bottom() - below.y();
  QPoint above = this->mapToGlobal(listRect.topLeft());
  int aboveHeight = above.y() - screen.y();
  bool boundToScreen = !this->window()->testAttribute(Qt::WA_DontShowOnScreen);

  const bool usePopup = style->styleHint(QStyle::SH_ComboBox_Popup, &opt, this);
    {
    int listHeight = 0;
    int count = 0;
    QStack<QModelIndex> toCheck;
    toCheck.push(this->view()->rootIndex());
#ifndef QT_NO_TREEVIEW
    QTreeView *treeView = qobject_cast<QTreeView*>(this->view());
    if (treeView && treeView->header() && !treeView->header()->isHidden())
      listHeight += treeView->header()->height();
#endif
    while (!toCheck.isEmpty())
      {
      QModelIndex parent = toCheck.pop();
      for (int i = 0; i < this->model()->rowCount(parent); ++i)
        {
        QModelIndex idx = this->model()->index(i, this->modelColumn(), parent);
        if (!idx.isValid())
          {
          continue;
          }
        listHeight += this->view()->visualRect(idx).height(); /* + container->spacing() */;
#ifndef QT_NO_TREEVIEW
        if (this->model()->hasChildren(idx) && treeView && treeView->isExpanded(idx))
          {
          toCheck.push(idx);
          }
#endif
        ++count;
        if (!usePopup && count > this->maxVisibleItems())
          {
          toCheck.clear();
          break;
          }
        }
      }
    listRect.setHeight(listHeight);
    }
      {
      // add the spacing for the grid on the top and the bottom;
      int heightMargin = 0;//2*container->spacing();

      // add the frame of the container
      int marginTop, marginBottom;
      container->getContentsMargins(0, &marginTop, 0, &marginBottom);
      heightMargin += marginTop + marginBottom;

      //add the frame of the view
      this->view()->getContentsMargins(0, &marginTop, 0, &marginBottom);
      //marginTop += static_cast<QAbstractScrollAreaPrivate *>(QObjectPrivate::get(this->view()))->top;
      //marginBottom += static_cast<QAbstractScrollAreaPrivate *>(QObjectPrivate::get(this->view()))->bottom;
      heightMargin += marginTop + marginBottom;

      listRect.setHeight(listRect.height() + heightMargin);
      }

      // Add space for margin at top and bottom if the style wants it.
      if (usePopup)
        {
        listRect.setHeight(listRect.height() + style->pixelMetric(QStyle::PM_MenuVMargin, &opt, this) * 2);
        }

      // Make sure the popup is wide enough to display its contents.
      if (usePopup)
        {
        const int diff = d->computeWidthHint() - this->width();
        if (diff > 0)
          {
          listRect.setWidth(listRect.width() + diff);
          }
        }

      //we need to activate the layout to make sure the min/maximum size are set when the widget was not yet show
      container->layout()->activate();
      //takes account of the minimum/maximum size of the container
      listRect.setSize( listRect.size().expandedTo(container->minimumSize())
                        .boundedTo(container->maximumSize()));

      // make sure the widget fits on screen
//.........这里部分代码省略.........

void VMdEditor::makeBlockVisible(const QTextBlock &p_block)
{
    if (!p_block.isValid() || !p_block.isVisible()) {
        return;
    }

    QScrollBar *vbar = verticalScrollBar();
    if (!vbar || (vbar->minimum() == vbar->maximum())) {
        // No vertical scrollbar. No need to scroll.
        return;
    }

    int height = rect().height();
    QScrollBar *hbar = horizontalScrollBar();
    if (hbar && (hbar->minimum() != hbar->maximum())) {
        height -= hbar->height();
    }

    bool moved = false;

    QAbstractTextDocumentLayout *layout = document()->documentLayout();
    QRectF rect = layout->blockBoundingRect(p_block);
    int y = GETVISUALOFFSETY;
    int rectHeight = (int)rect.height();

    // Handle the case rectHeight >= height.
    if (rectHeight >= height) {
        if (y < 0) {
            // Need to scroll up.
            while (y + rectHeight < height && vbar->value() > vbar->minimum()) {
                moved = true;
                vbar->setValue(vbar->value() - vbar->singleStep());
                rect = layout->blockBoundingRect(p_block);
                rectHeight = (int)rect.height();
                y = GETVISUALOFFSETY;
            }
        } else if (y > 0) {
            // Need to scroll down.
            while (y > 0 && vbar->value() < vbar->maximum()) {
                moved = true;
                vbar->setValue(vbar->value() + vbar->singleStep());
                rect = layout->blockBoundingRect(p_block);
                rectHeight = (int)rect.height();
                y = GETVISUALOFFSETY;
            }

            if (y < 0) {
                // One step back.
                moved = true;
                vbar->setValue(vbar->value() - vbar->singleStep());
            }
        }

        if (moved) {
            qDebug() << "scroll to make huge block visible";
        }

        return;
    }

    while (y < 0 && vbar->value() > vbar->minimum()) {
        moved = true;
        vbar->setValue(vbar->value() - vbar->singleStep());
        rect = layout->blockBoundingRect(p_block);
        rectHeight = (int)rect.height();
        y = GETVISUALOFFSETY;
    }

    if (moved) {
        qDebug() << "scroll page down to make block visible";
        return;
    }

    while (y + rectHeight > height && vbar->value() < vbar->maximum()) {
        moved = true;
        vbar->setValue(vbar->value() + vbar->singleStep());
        rect = layout->blockBoundingRect(p_block);
        rectHeight = (int)rect.height();
        y = GETVISUALOFFSETY;
    }

    if (moved) {
        qDebug() << "scroll page up to make block visible";
    }
}