c# - Avalondock-某些面板的布局恢复延迟

Question

我使用的加载/保存布局类似于CodeProject所述。捕获LayoutSerializationCallback事件并尝试为LayoutItem查找相应的viewModel

private void LayoutSerializer_LayoutSerializationCallback(object sender, LayoutSerializationCallbackEventArgs e)
        {
            // This can happen if the previous session was loading a file
            // but was unable to initialize the view ...
            if (string.IsNullOrWhiteSpace(e.Model.ContentId) || (e.Content = ReloadItem(e.Model)) == null)
            {
                e.Cancel = true;
                return;
            }
        }

private object ReloadItem(object item)
{
    object ret = null;

    switch (item)
    {
        case LayoutAnchorable anchorable:
            //list of tools windows
            ret = Manager.Tools.FirstOrDefault(i => i.ContentId == anchorable.ContentId);
            if(ret == null && anchorable.ContentId.StartsWith(MapPanel.MapPanelPrefix))
            {

                MapPanels.Add(anchorable);
            }
            break;
        case LayoutDocument document:
            // list of restored documents
            ret = Manager.Documents.FirstOrDefault(i => i.ContentId == document.ContentId);
            break;
        default:
            throw new NotImplementedException("Not implemented type of AD item ");
    }

    return ret;

}

反序列化/还原布局时，当我有所有可用的ViewModels时，这可以很好地工作。

但是我正在考虑延迟布局还原之类的事情。就我而言，一开始我有一些文档和一些面板。但是可能会有一些面板(称为MapPanel)在以后加载(viewModels在将来加载)。而且我不知道如何恢复这些面板的布局。

对于这种情况，我具有List MapPanels来存储在avalondock布局加载时加载的可 anchor 定 map ，并尝试在ILayoutUpdateStrategy的BeforeInsertAnchorable中还原它们。但是当我调试它时，存储的LayoutAnchorable具有存储一个的不同父项。因此，我假设在LayoutSerializationCallback中取消(e.Cancel = true)后，会以某种方式修改无法恢复的 anchor 定。

public bool BeforeInsertAnchorable(LayoutRoot layout, LayoutAnchorable anchorableToShow, ILayoutContainer destinationContainer)
        {
            if (anchorableToShow.Content is ToolPanel tool)
            {

                if(tool is MapPanel)
                {
                    anchorableToShow = LayoutSaveLoadUtil.Instance.MapPanels.FirstOrDefault(mp => mp.ContentId == anchorableToShow.ContentId);
                }

                var destPane = destinationContainer as LayoutAnchorablePane;
                if (destinationContainer != null && destinationContainer.FindParent<LayoutFloatingWindow>() != null)
                    return false;


                var dockLeftPane = layout.Descendents().OfType<LayoutAnchorablePane>().FirstOrDefault(d => d.Name == tool.PreferredLocation + "Pane");
                if (dockLeftPane != null)
                {
                    dockLeftPane.Children.Add(anchorableToShow);
                    return true;
                }

                return false;
            }

            return false;

        }

所以我很好奇实现此目标的正确方法。我还考虑过在加载MapPanel之后(再次)恢复布局，但是我不知道如何跳过所有其他LayoutItems。那么，是否有可能恢复单个Anchorable位置， float 父对象，停靠，尺寸等...？

Answer 1

所以我大概想出了解决方案。

我有一些面板(称为MapPanel)，并且从XML恢复布局时不会加载theyr的内容。以我为例，我有一个具有一些文档和选项卡的应用程序，并且在其他情况下，用户可以加载其他数据以显示 map 。

当用户加载 map 时，我需要恢复此 map 的布局。 (单击按钮，选择在哪里加载 map 等)

当我有LayoutAnchorable类型的附加列表MapPanelsStorage时，我有一个名为LayoutSaveLoadUtil的静态类(如代码项目中所述)。在此列表中，我存储了在布局还原中缺少内容且ContentId具有特定前缀的所有布局。这告诉我是MapPanel。然后，我创建一个虚拟内容，将其分配给此面板并将其可见性设置为false(因此面板不可见)

(这在layoutSerializationCallback中称为)

private object ReloadItem(object item)
{
    object ret = null;

    switch (item)
    {
        case LayoutAnchorable anchorable:
            //list of tools windows
            ret = Manager.Tools.FirstOrDefault(i => i.ContentId == anchorable.ContentId);
            if(ret == null && anchorable.ContentId.StartsWith(MapPanel.MapPanelPrefix))
            {
                //when layoutAnchorable is MapPanel (has MapPanel prefix) and its content is loaded yet
                //store its layout into list to restore it later (when content is loaded)
                MapPanelsStorage.Add(anchorable);
                //Set anchorable visibility to false 
                anchorable.IsVisible = false;
                //return dummy model for avalondock layout serialization
                ret = new EmptyMapViewModel();
            }
            break;
        case LayoutDocument document:
            // list of restored documents
            ret = Manager.Documents.FirstOrDefault(i => i.ContentId == document.ContentId);
            break;
        default:
            throw new NotImplementedException("Not implemented type of AD item ");
    }

    return ret;

}

然后在BeforeInsertAnchorable(将新面板添加到布局中时调用)中，我检查面板内容是否为MapPanel，查找存储的布局，尝试查找父项(LayoutAnchorablePane/LayoutDocumentPane)，然后添加它而不是DummyHidden面板，然后将其从存储中删除。

//hacky hacky to restore map panel layout when map is opened after layout is loaded
//in layout deserialization, deserialize layout for MapPanels that hasnt DataModels yet with DummyModel to preserve their layout
if (anchorableToShow.Content is MapPanel mappanel)
{
    var storedMapsLayout = LayoutSaveLoadUtil.Instance.MapPanelsStorage;

    //check if Map panel has stored layout from previous layout deserialization
    var matchingAnchorable = storedMapsLayout.FirstOrDefault(m => m.ContentId == mappanel.ContentId);
    if (matchingAnchorable != null)
    {
        //make preserved layout visible, so its parent and etc is restored. Without this, correct parent LayoutGroup isnt found
        matchingAnchorable.IsVisible = true;

        LayoutAnchorablePane matchingAnchorablePane;
        LayoutDocumentPane matchingDocumentPane;

        //find parent layoutGroup. This can be LayoutAnchorablePane or LayoutDocumentPane
        if ((matchingAnchorablePane = matchingAnchorable.FindParent<LayoutAnchorablePane>()) != null)
        {
            //add new panel into layoutGroup with correct layout
            matchingAnchorablePane.Children.Add(anchorableToShow);
            //remove old dummy panel
            matchingAnchorablePane.RemoveChild(matchingAnchorable);
            //remove restored layout from storage
            storedMapsLayout.Remove(matchingAnchorable);
            return true;
        }
        else if ((matchingDocumentPane = matchingAnchorable.FindParent<LayoutDocumentPane>()) != null)
        {
            //add new panel into layoutGroup with correct layout
            matchingDocumentPane.Children.Add(anchorableToShow);
            //remove old dummy panel
            matchingDocumentPane.RemoveChild(matchingAnchorable);
            //remove restored layout from storage
            storedMapsLayout.Remove(matchingAnchorable);
            return true;
        }
        else
        {
            matchingAnchorable.IsVisible = false;
        }
    }
}