c# - 如何实现具有最低高度要求的 Telerik RadPageView？

Question

我的 Telerik RadPageView 控件(Q2 2011 SP1)在我的 winforms C# 应用程序中设置为 ViewMode“Outlook”。在我的要求中，我有一个有限的空间来显示控件(大约 600px 的高度)。当控件添加了超过 5 个页面时， View 面板(页面选择器上方的开放区域)变小并切断内容(下面屏幕截图中的黄色区域)。我想知道是否有办法在这个区域强制执行最小高度，以便控件自动折叠它无法适应这个受限空间的页面选择器。我需要每页大约 300 像素的高度。

我已经尝试在每个 RadPageViewPage 上设置 MinimumSize 属性。但是，当我这样做时，页面 View 页面“溢出”到页面选择器的顶部。我原以为 handle (控件的可拖动部分)会自动调整大小以满足最低高度要求。

请查看下面我的示例应用程序的屏幕截图:

问题:

期望:

更新:

我能够创建一个函数，在“初始化”或“调整大小”事件触发时以编程方式调整 handle 位置。我意识到当所选页面也发生变化时，我很可能需要调用此函数。

无论如何，这是片段:

private void adjustPageViewGrip()
{
    RadPageViewOutlookElement viewElement = (RadPageViewOutlookElement)radPageView.ViewElement;
    int minHeight = 300;
    int itemHeight = radPageView.SelectedPage.Item.Size.Height;
    int selectedPageHeight = radPageView.SelectedPage.Height;

    if (selectedPageHeight < minHeight)
    {
        int hide = (int)Math.Ceiling((double)(minHeight - selectedPageHeight) / (double)itemHeight);
        if (hide > 0)
        {
            viewElement.HideItems(hide);
        }
    }
    else if ((selectedPageHeight + itemHeight) >= minHeight)
    {
        int show = (int)Math.Floor((double)(selectedPageHeight - minHeight) / (double)itemHeight);
        if (show > 0)
        {
            viewElement.ShowItems(show);
        }
    }
}

我仍然很好奇我是否需要这段代码。控件已经可以做到这一点了吗？

Answer 1

我发布了同样的 question在 Telerik 论坛上，发现该控件实际上不支持我上面提出的问题。

最后，我调整了函数来计算所需的高度，而不是对它们进行硬编码。一旦计算出高度，该函数就会显示或隐藏所需的正确页数。该函数现在由扩展类中的 OnLoad、Initialized、Resized 和 SelectedPageChanged 事件调用。我还通过折叠 OutlookViewOverflowGrip 使它不可见，我依靠新代码为我调整它的位置。

这是最终结果的代码:

/// <summary>
/// Adjusts the position of the Outlook overflow grip.
/// </summary>
public void AdjustOutlookViewOverflowGrip()
{
    if (ViewMode == PageViewMode.Outlook && SelectedPage != null)
    {
        // Fix rendering bug by hiding RadPageViewPage's that are not currently selected
        foreach (RadPageViewPage page in Pages)
        {
            if (page == SelectedPage)
            {
                page.Show();
            }
            else
            {
                page.Hide();
            }
        }

        // Elements from control
        RadPageViewOutlookElement outlookElement = (RadPageViewOutlookElement)ViewElement;
        OverflowItemsContainer overflowItemsContainer = (OverflowItemsContainer)GetChildAt(0).GetChildAt(4);

        // Selected page and item heights
        int selectedPageMinHeight = (SelectedPage.MinimumSize.Height > ContentMinimumHeight ? SelectedPage.MinimumSize.Height : contentMinimumHeight);
        int pageSelectorHeight = SelectedPage.Item.Size.Height;

        // Show or hide items
        if (pageSelectorHeight > 0 && selectedPageMinHeight > 0)
        {
            // Calculate content area height
            int contentAreaHeight =                 
                (
                    Size.Height -
                    (
                        from element in ((RadPageViewOutlookElement)ViewElement).Children
                        where
                        (
                            element.Visibility != ElementVisibility.Collapsed
                            &&
                            (
                                element is RadPageViewLabelElement
                                || element is OutlookViewOverflowGrip
                                || element is RadPageViewOutlookItem
                                || element is OverflowItemsContainer
                            )
                        )
                        select element.Size.Height + element.Margin.Vertical
                    )
                    .Sum()
                );

            if (contentAreaHeight < selectedPageMinHeight)
            {
                // Factor in OverflowItemsContainer height if it's currently collapsed
                int overflowItemsHeight = (overflowItemsContainer.Visibility == ElementVisibility.Collapsed ? overflowItemsContainer.Size.Height : 0);

                // Not enough space available... hide items
                int hide = (int)Math.Ceiling((double)(selectedPageMinHeight - contentAreaHeight + overflowItemsHeight) / (double)pageSelectorHeight);
                if (hide > 0)
                {
                    outlookElement.HideItems(hide);
                }
            }
            else if (contentAreaHeight >= (selectedPageMinHeight + pageSelectorHeight))
            {
                // More space available... show items
                int show = (int)Math.Floor((double)(contentAreaHeight - selectedPageMinHeight) / (double)pageSelectorHeight);
                if (show > 0)
                {
                    outlookElement.ShowItems(show);
                }
            }
        }

        // Set overflow container visiblity
        overflowItemsContainer.Visibility = (outlookElement.GetHiddenItems().Length > 0 ? ElementVisibility.Visible : ElementVisibility.Collapsed);
    }
}