Question

我在现有架构中有一个奇怪的场景，现在已经开发了一段时间。该体系结构使用View-First在自定义MS Office应用程序中支持Caliburn Micro，该应用程序在MS Office任务窗格中使用WPF内容。由于没有顶级Application对象，我在每个任务窗格中使用自定义Bootstrapper和一组代理顶级内容“hosts”。 View-First顶级主机是单个项目的每个Conductors。在应用程序启动时初始化主机后，我只需将单个子项导入每个主机，然后利用ViewModel-First方法编写每个任务窗格的内容。

我现在正尝试使用

的样式引入View Context切换以支持备用视图

<ContentControl cal:View.Context="{Binding TaskPaneState}" cal:View.Model="{Binding}" />

其中TaskPaneState是我的Viewmodels上的一个可观察属性，可以解析为“最大化”或“最小化”。

我组织了视图文件夹来支持这些上下文，所以我有Minimized.xaml，Maximized.xaml等。

但是，在测试这种方法时，我现在在尝试解析/加载/绑定时遇到无限循环：

2014-03-24 14:52:23.5904|INFO|Caliburn.Micro.Action|Setting DC of Corp.Control.Design.Views.Book.BookDesignerView to BookDesignerViewModel(Basic Budget Example).
2014-03-24 14:52:23.5904|INFO|Caliburn.Micro.Action|Attaching message handler BookDesignerViewModel(Basic Budget Example) to Corp.Control.Design.Views.Book.BookDesignerView.
2014-03-24 14:52:23.6094|INFO|Caliburn.Micro.Action|Setting DC of Corp.Control.Design.Views.Book.BookDesignerView to BookDesignerViewModel(Basic Budget Example).
2014-03-24 14:52:23.6094|INFO|Caliburn.Micro.Action|Attaching message handler BookDesignerViewModel(Basic Budget Example) to Corp.Control.Design.Views.Book.BookDesignerView.
2014-03-24 14:52:23.6314|INFO|Caliburn.Micro.Action|Setting DC of Corp.Control.Design.Views.Book.BookDesignerView to BookDesignerViewModel(Basic Budget Example).
2014-03-24 14:52:23.6314|INFO|Caliburn.Micro.Action|Attaching message handler BookDesignerViewModel(Basic Budget Example) to Corp.Control.Design.Views.Book.BookDesignerView.
2014-03-24 14:52:23.6474|INFO|Caliburn.Micro.Action|Setting DC of Corp.Control.Design.Views.Book.BookDesignerView to BookDesignerViewModel(Basic Budget Example).
2014-03-24 14:52:23.6474|INFO|Caliburn.Micro.Action|Attaching message handler BookDesignerViewModel(Basic Budget Example) to Corp.Control.Design.Views.Book.BookDesignerView.
2014-03-24 14:52:23.6664|INFO|Caliburn.Micro.Action|Setting DC of Corp.Control.Design.Views.Book.BookDesignerView to BookDesignerViewModel(Basic Budget Example).
2014-03-24 14:52:23.6664|INFO|Caliburn.Micro.Action|Attaching message handler BookDesignerViewModel(Basic Budget Example) to Corp.Control.Design.Views.Book.BookDesignerView.
2014-03-24 14:52:23.6904|INFO|Caliburn.Micro.Action|Setting DC of Corp.Control.Design.Views.Book.BookDesignerView to BookDesignerViewModel(Basic Budget Example).
2014-03-24 14:52:23.6904|INFO|Caliburn.Micro.Action|Attaching message handler BookDesignerViewModel(Basic Budget Example) to Corp.Control.Design.Views.Book.BookDesignerView.
2014-03-24 14:52:23.7104|INFO|Caliburn.Micro.Action|Setting DC of Corp.Control.Design.Views.Book.BookDesignerView to BookDesignerViewModel(Basic Budget Example).
2014-03-24 14:52:23.7104|INFO|Caliburn.Micro.Action|Attaching message handler BookDesignerViewModel(Basic Budget Example) to Corp.Control.Design.Views.Book.BookDesignerView.
2014-03-24 14:52:23.7534|INFO|Caliburn.Micro.Action|Setting DC of Corp.Control.Design.Views.Book.BookDesignerView to BookDesignerViewModel(Basic Budget Example).
2014-03-24 14:52:23.7534|INFO|Caliburn.Micro.Action|Attaching message handler BookDesignerViewModel(Basic Budget Example) to Corp.Control.Design.Views.Book.BookDesignerView.

我对可能造成这种无限循环的原因感到茫然。

编辑：

所以我更新了我的解决方案以使用Caliburn Micro的2.0.x Beta版本，我的行为更好，但仍有些异常。循环仍然发生但不是无限的。我得到大约250多个循环，然后事情稳定下来，View加载。从我在调试器中可以看出，如果我在View.OnModelChanged和View.OnContextChanged上放置一个断点，调试器将在这两个断点之间翻转大约250次（见下面的日志）。我也尝试过为View.Context使用TwoWay绑定，但这似乎没什么区别......还在挠我的头......

这是最新的日志：

    2014-04-01 11:57:53.0681|INFO|Caliburn.Micro.Action|Setting DC of .Control.AddIn.Views.ObjectNavigationTaskPaneHostView to .Control.AddIn.ViewModels.ObjectNavigationTaskPaneHostViewModel.
    2014-04-01 11:57:53.0741|INFO|Caliburn.Micro.Action|Attaching message handler .Control.AddIn.ViewModels.ObjectNavigationTaskPaneHostViewModel to .Control.AddIn.Views.ObjectNavigationTaskPaneHostView.
    2014-04-01 11:57:53.0741|INFO|.Control.AddIn.ViewModels.TaskPaneHostViewModel|ObjectNavigationTaskPaneHostViewModel OnViewLoaded
    2014-04-01 11:57:53.0741|INFO|.Control.AddIn.ViewModels.TaskPaneHostViewModel|ObjectNavigationTaskPaneHostViewModel OnViewAttached
    2014-04-01 11:57:53.0741|INFO|Caliburn.Micro.ConventionManager|ViewModel bound on ActiveItem.
    2014-04-01 11:57:53.0741|INFO|Caliburn.Micro.Screen|Activating .Control.AddIn.ViewModels.ObjectNavigationTaskPaneHostViewModel.
    2014-04-01 11:57:53.0891|INFO|.Control.AddIn.Views.TaskPaneHostView|Entering : ActivateContent
    2014-04-01 11:57:53.0891|INFO|.Control.AddIn.ViewModels.TaskPaneHostViewModel|ObjectNavigationTaskPaneHostViewModel Queued content viewmodel ObjectNavigationViewModel
    2014-04-01 11:57:53.0891|INFO|.Control.AddIn.Views.TaskPaneHostView|Exiting: ActivateContent
    2014-04-01 11:57:53.1221|INFO|.Control.AddIn.ViewModels.TaskPaneHostViewModel|ObjectNavigationTaskPaneHostViewModel OnViewReady
    2014-04-01 11:57:53.1221|INFO|.Control.AddIn.ViewModels.TaskPaneHostViewModel|ActivateItem(ObjectNavigationViewModel '.Control.ViewModels.ObjectNavigation.ObjectNavigationViewModel')
    2014-04-01 11:57:53.1221|INFO|Caliburn.Micro.Screen|Activating ObjectNavigationViewModel '.Control.ViewModels.ObjectNavigation.ObjectNavigationViewModel'.
    2014-04-01 11:57:53.1591|INFO|Caliburn.Micro.Action|Setting DC of .Control.Views.ObjectNavigation.ObjectNavigationView to ObjectNavigationViewModel '.Control.ViewModels.ObjectNavigation.ObjectNavigationViewModel'.
    2014-04-01 11:57:53.1591|INFO|Caliburn.Micro.Action|Attaching message handler ObjectNavigationViewModel '.Control.ViewModels.ObjectNavigation.ObjectNavigationViewModel' to .Control.Views.ObjectNavigation.ObjectNavigationView.
    2014-04-01 11:57:53.1591|INFO|Caliburn.Micro.ConventionManager|ContentTemplate applied to Items.
    2014-04-01 11:57:53.1591|INFO|Caliburn.Micro.ConventionManager|SelectedItem binding applied to Items.
    2014-04-01 11:57:53.1811|INFO|Caliburn.Micro.Screen|Activating ObjectTypeNavigationViewModel 'Browse CONTROL classes by Type'.
    2014-04-01 11:57:53.3491|INFO|Caliburn.Micro.Action|Setting DC of .Control.Views.ObjectNavigation.ObjectTypeNavigationView to ObjectTypeNavigationViewModel 'Browse CONTROL classes by Type'.
    2014-04-01 11:57:53.3491|INFO|Caliburn.Micro.Action|Attaching message handler ObjectTypeNavigationViewModel 'Browse CONTROL classes by Type' to .Control.Views.ObjectNavigation.ObjectTypeNavigationView.
    2014-04-01 11:57:53.3661|INFO|Caliburn.Micro.Action|Attaching message handler ObjectNavigationViewModel '.Control.ViewModels.ObjectNavigation.ObjectNavigationViewModel' to .Control.Windows.Common.KCIContextMenu Items.Count:1.
    2014-04-01 11:58:05.0291|INFO|.Control.AddIn.Views.TaskPaneHostView|Entering : DeactivateContent
    2014-04-01 11:58:05.0291|INFO|.Control.AddIn.Views.TaskPaneHostView|Exiting: DeactivateContent
    2014-04-01 11:58:08.2491|INFO|Caliburn.Micro.Action|Setting DC of .Control.AddIn.Views.DesignerTaskPaneHostView: Active Designer to .Control.AddIn.ViewModels.DesignerTaskPaneHostViewModel.
    2014-04-01 11:58:08.2491|INFO|Caliburn.Micro.Action|Attaching message handler .Control.AddIn.ViewModels.DesignerTaskPaneHostViewModel to .Control.AddIn.Views.DesignerTaskPaneHostView: Active Designer.
    2014-04-01 11:58:08.2511|INFO|.Control.AddIn.ViewModels.TaskPaneHostViewModel|DesignerTaskPaneHostViewModel OnViewLoaded
    2014-04-01 11:58:08.2511|INFO|.Control.AddIn.ViewModels.TaskPaneHostViewModel|DesignerTaskPaneHostViewModel OnViewAttached
    2014-04-01 11:58:08.2511|INFO|Caliburn.Micro.ConventionManager|ViewModel bound on ActiveItem.
    2014-04-01 11:58:08.2511|INFO|Caliburn.Micro.Screen|Activating .Control.AddIn.ViewModels.DesignerTaskPaneHostViewModel.
    2014-04-01 11:58:08.2511|INFO|.Control.AddIn.Views.TaskPaneHostView|Entering : ActivateContent
    2014-04-01 11:58:08.2511|INFO|.Control.AddIn.ViewModels.TaskPaneHostViewModel|DesignerTaskPaneHostViewModel Queued content viewmodel BookDesignerViewModel
    2014-04-01 11:58:08.2511|INFO|.Control.AddIn.Views.TaskPaneHostView|Exiting: ActivateContent
    2014-04-01 11:58:08.2841|INFO|.Control.AddIn.ViewModels.TaskPaneHostViewModel|DesignerTaskPaneHostViewModel OnViewReady
    2014-04-01 11:58:08.2841|INFO|.Control.AddIn.ViewModels.TaskPaneHostViewModel|ActivateItem(BookDesignerViewModel(Basic Budget Example))
    2014-04-01 11:58:08.2841|INFO|Caliburn.Micro.Screen|Activating BookDesignerViewModel(Basic Budget Example).
    2014-04-01 11:58:08.2841|INFO|Caliburn.Micro.Action|Setting DC of .Control.Design.Views.Book.BookDesignerView to BookDesignerViewModel(Basic Budget Example).
    2014-04-01 11:58:08.2841|INFO|Caliburn.Micro.Action|Attaching message handler BookDesignerViewModel(Basic Budget Example) to .Control.Design.Views.Book.BookDesignerView. 

<snip around 500 lines> 

2014-04-01 11:58:08.2841|INFO|Caliburn.Micro.Action|Setting DC of .Control.Design.Views.Book.BookDesignerView to BookDesignerViewModel(Basic Budget Example).
    2014-04-01 11:58:08.2841|INFO|Caliburn.Micro.Action|Attaching message handler BookDesignerViewModel(Basic Budget Example) to .Control.Design.Views.Book.BookDesignerView.
2014-04-01 11:58:08.2841|INFO|Caliburn.Micro.Action|Setting DC of .Control.Design.Views.Book.BookDesignerView to BookDesignerViewModel(Basic Budget Example).
    2014-04-01 11:58:08.2841|INFO|Caliburn.Micro.Action|Attaching message handler BookDesignerViewModel(Basic Budget Example) to .Control.Design.Views.Book.BookDesignerView.
2014-04-01 11:58:08.2841|INFO|Caliburn.Micro.Action|Setting DC of .Control.Design.Views.Book.BookDesignerView to BookDesignerViewModel(Basic Budget Example).
    2014-04-01 11:58:08.2841|INFO|Caliburn.Micro.Action|Attaching message handler BookDesignerViewModel(Basic Budget Example) to .Control.Design.Views.Book.BookDesignerView.


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Answer 1

所以你有一个名为BookDesignerViewModel的视图模型，我假设你有BookDesignerView作为你的视图。然后你有一个名为BookDesigner的文件夹（纯粹用于Views文件夹下的结构），该文件夹包含该BookDesigner文件夹中包含的Max / Min .xaml（缩短）文件？

其次你尝试过设置cal：View.Context =＆＃34; {Binding TaskPaneState， Mode = TwoWay }＆＃34; ？我知道在以前的答案中，你问为什么考虑到有关该物业的通知性质已经完成，说实话我没有多考虑因为它是我在学习时看过的例子的一部分CM，它是示例HelloScreens，它以完整的细节显示视图切换。

Answer 2

我还在测试，但我相信至少有两个问题我已经解决了。

首先，在ContentControl上查看View附加属性的顺序似乎很重要。这是我正在使用的订单：

<ContentControl cal:View.Context="{Binding TaskPaneState}" cal:View.Model="{Binding}" />

我不需要在Context属性上使用TwoWay绑定。

此外，如果出于某种原因，View.OnModelChanged所看到的Context属性的值不会解析为与系统上的真实视图对应的视图，则父View可能是返回并导致递归。

目前我还在测试，但暂时看起来很稳定。

使用View-First和View Context切换时的无限循环加载视图

2 个答案: