Question

当我通过NuGet添加MVVM Light包时，我会在安装期间添加引用App.xaml文件中的行的错误。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>

这些行位于结尾＆lt; /Application.Resources> 标记之前。 “错误列表”窗格中报告的错误是：

每个字典必须有一个关联的密钥
名称“ViewModelLocator”在名称空间“clr-namespace：sdkVoiceAlarmClockWP8CS.ViewModel”中不存在

这似乎有意义，因为＆lt; ResourceDictionary＆gt; 标记没有键属性。但是，如果我尝试在块之外移动这一行，我会得到一组全新的错误。

就ViewModelLocator问题而言，我进行了双重检查，并将以下命名空间作为属性添加到＆lt; Application＆gt; 标记中，并且未标记任何错误：

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

为什么这一组完全相同的行在Windows Phone 7项目中运行良好？如何解决我在Windows Phone 8项目中遇到的命名空间问题？

以防这是一个更复杂的问题，这是整个 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

之前我遇到过这个问题。为了使它在WP8中工作，请替换为：

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

只有这个：

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

但我并不担心为什么它适用于WP7但不适用于WP8

Answer 2

将所有内容插入到ResourceDictionary中，而不是在具有所有必需名称空间的ApplicationResources中，如本stackoverflow question中所述。

App.xaml中的错误试图在Windows Phone 8项目中使用MVVM Light

2 个答案: