尝试在Windows Phone 8项目中使用MVVM Light的App.xaml中的错误

Question

当我通过NuGet添加MVVM Light软件包时，出现错误，引用了在安装过程中添加的App.xaml文件中的行。 这些错误仅出现在Windows Phone 8项目中。 Windows Phone 7项目中完全相同的行不会引发任何错误。 MVVM Light添加的行是：

<ResourceDictionary>
    <vm:ViewModelLocator x:Key="Locator" d:IsDataSource="True" />
     <ResourceDictionary.MergedDictionaries></ResourceDictionary.MergedDictionaries>
</ResourceDictionary>

这些行位于</Application.Resources>标记的紧前面。 在“错误列表”窗格中报告的错误为：

• 每个字典必须具有关联的键
• 名称空间“ clr-namespace：sdkVoiceAlarmClockWP8CS.ViewModel”中不存在名称“ ViewModelLocator”

这似乎是有道理的，因为<ResourceDictionary>标记没有键属性。 但是，如果我尝试将此线段移到 块，我得到了一套全新的错误。

就ViewModelLocator问题而言，我进行了仔细检查，并将以下名称空间作为属性添加到<Application>标记中，并且未将其标记为任何错误：

xmlns:vm="clr-namespace:sdkVoiceAlarmClockWP8CS.ViewModel" mc:Ignorable="d"

为什么这组完全相同的行在Windows Phone 7项目中可以正常工作，如何解决我在Windows Phone 8项目中遇到的名称空间问题？

万一这是由于更复杂的问题引起的，下面是整个App.xaml文件：

<?xml version="1.0" encoding="utf-8"?>
<!-- 
    Copyright (c) 2012 Microsoft Corporation.  All rights reserved.
    Use of this sample source code is subject to the terms of the Microsoft license 
    agreement under which you licensed this sample source code and is provided AS-IS.
    If you did not accept the terms of the license agreement, you are not authorized 
    to use this sample source code.  For the terms of the license, please see the 
    license agreement between you and Microsoft.

    To see all Code Samples for Windows Phone, visit http://go.microsoft.com/fwlink/?LinkID=219604
-->
<Application x:Class="AlarmClockWithVoice.App" 
             xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone" 
             xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone" 
             xmlns:toolkit="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls.Toolkit" 
             xmlns:telerikPrimitives="clr-namespace:Telerik.Windows.Controls;assembly=Telerik.Windows.Controls.Primitives" 
             xmlns:p1="http://schemas.microsoft.com/winfx/2006/xaml" 
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:vm="clr-namespace:sdkVoiceAlarmClockWP8CS.ViewModel" mc:Ignorable="d"
             >

    <!--Application Resources-->
    <Application.Resources>
        <Style x:Key="TransitionPageStyle" TargetType="phone:PhoneApplicationPage">
            <Setter Property="toolkit:TransitionService.NavigationInTransition">
                <Setter.Value>
                    <toolkit:NavigationInTransition>
                        <toolkit:NavigationInTransition.Backward>
                            <toolkit:TurnstileTransition Mode="BackwardIn" />
                        </toolkit:NavigationInTransition.Backward>
                        <toolkit:NavigationInTransition.Forward>
                            <toolkit:TurnstileTransition Mode="ForwardIn" />
                        </toolkit:NavigationInTransition.Forward>
                    </toolkit:NavigationInTransition>
                </Setter.Value>
            </Setter>
            <Setter Property="toolkit:TransitionService.NavigationOutTransition">
                <Setter.Value>
                    <toolkit:NavigationOutTransition>
                        <toolkit:NavigationOutTransition.Backward>
                            <toolkit:TurnstileTransition Mode="BackwardOut" />
                        </toolkit:NavigationOutTransition.Backward>
                        <toolkit:NavigationOutTransition.Forward>
                            <toolkit:TurnstileTransition Mode="ForwardOut" />
                        </toolkit:NavigationOutTransition.Forward>
                    </toolkit:NavigationOutTransition>
                </Setter.Value>
            </Setter>
        </Style>
        <ResourceDictionary>
            <vm:ViewModelLocator x:Key="Locator" d:IsDataSource="True" />
            <ResourceDictionary.MergedDictionaries></ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </Application.Resources>

    <Application.ApplicationLifetimeObjects>
        <!--Required object that handles lifetime events for the application-->
        <shell:PhoneApplicationService Launching="Application_Launching" Closing="Application_Closing" Activated="Application_Activated" Deactivated="Application_Deactivated" />
    </Application.ApplicationLifetimeObjects>

</Application>

Answer 1

我以前有这个问题。 要使其在WP8中工作，请替换为：

<ResourceDictionary>
    <vm:ViewModelLocator x:Key="Locator" d:IsDataSource="True" />
    <ResourceDictionary.MergedDictionaries></ResourceDictionary.MergedDictionaries>
</ResourceDictionary>

有了这个：

<vm:ViewModelLocator x:Key="Locator" d:IsDataSource="True" />

但是我没有为它为什么可以在WP7上工作而不是在WP8上工作而烦恼

Answer 2

将所有内容插入具有所有必要名称空间的ResourceDictionary中，而不是插入ApplicationResources中，如本stackoverflow问题中所述 。