void ToolBarAreaImpl::layoutToolBarRowPart
(ToolBarList& toolBars, int rowTop, int rowHeight, int partLeft, int partRight)
{
    // find the index of the tool bar with the maximum priority
    int pivotIndex = 0;
    int maxPriority = -1;
    for(size_t i=0; i < toolBars.size(); ++i){
        if(toolBars[i]->layoutPriority > maxPriority){
            maxPriority = toolBars[i]->layoutPriority;
            pivotIndex = i;
        }
    }

    ToolBarList leftPartToolBars;
    int pivotAreaLeft = partLeft;
    for(int i=0; i < pivotIndex; ++i){
        leftPartToolBars.push_back(toolBars[i]);
        pivotAreaLeft += toolBars[i]->minimumSizeHint().width();
    }

    ToolBarList rightPartToolBars;
    int pivotAreaRight = partRight;
    for(size_t i = pivotIndex + 1; i < toolBars.size(); ++i){
        rightPartToolBars.push_back(toolBars[i]);
        pivotAreaRight -= toolBars[i]->minimumSizeHint().width();
    }

    ToolBar* pivotToolBar = toolBars[pivotIndex];
    int x = pivotToolBar->desiredX;
    const QSize size = pivotToolBar->minimumSizeHint();
    int width = size.width();
    if(width < 0){
        width = 0;
    }
    if(x + width > pivotAreaRight){
        x = pivotAreaRight - width;
    }
    if(x < pivotAreaLeft){
        x = pivotAreaLeft;
    }

    if(!leftPartToolBars.empty()){
        layoutToolBarRowPart(leftPartToolBars, rowTop, rowHeight, partLeft, x);
        QRect r = leftPartToolBars.back()->geometry();
        int leftPartRight = r.x() + r.width();
        if(x <= leftPartRight){
            x = leftPartRight + 1;
        }
    }

    int rightPartLeft = partRight;
    if(!rightPartToolBars.empty()){
        layoutToolBarRowPart(rightPartToolBars, rowTop, rowHeight, x + width, partRight);
        rightPartLeft = rightPartToolBars.front()->geometry().x();
    }

    if(pivotToolBar->isStretchable()){
        width = pivotToolBar->maximumWidth();
        int possibleWidth = rightPartLeft - x;
        if(width > possibleWidth){
            width = possibleWidth;
        }
    }

    int height = (size.height() >= 0) ? size.height() : rowHeight;
    int y = rowTop + (rowHeight - height) / 2;

    pivotToolBar->setGeometry(x, y, width, height);
    pivotToolBar->show();
}