Windows phone 7 MVVMWP7-页面导航和转换动画

我是WP7中MVVM模型的初学者。我很难实现页面之间的导航和动画转换

我想要达到的目标：

当第1页导航到第2页时，将启动过渡动画动画1，但当第1页导航到第3页时，将启动不同的过渡动画动画2

ViewModel可以取消GoBack导航，例如，当搜索模式打开时（文本框可见，用户按back键后，文本框将隐藏，ViewModel将切换到搜索模式关闭，并阻止页面向后导航）

我创造了这样的东西：

<Navigation>
        <NavigationInTransition>
            <NavigationInTransition.ForwardTransitions>
                <ForwardTransition NavigateTo="page2.xaml">
                    <ForwardTransition.Animation>
                        <SlideTransitionAnimation Mode="ForwardIn"/>
                    </ForwardTransition.Animation>
                </ForwardTransition>
                <ForwardTransition NavigateTo="page3.xaml">
                    <ForwardTransition.Animation>
                        <TurnstyleTransitionAnimation Mode="ForwardIn"/>
                    </ForwardTransition.Animation>
                </ForwardTransition>
            </NavigationInTransition.ForwardTransitions>
        </NavigationInTransition>
        <BackKeyPressed IsPrevent="{Binding SomethingBool}" Command="{Binding BackKeyPressed}"/>
</Navigation>

ExtendedPhoneApplicationPage:PhoneApplicationPage-特殊控件，继承自PhoneApplicationPage，通过接口调用对ViewModel的请求

MainViewModel:INavigation-MainViewModel，它是ViewModel，并实现接口INavigation

它是如何工作的

用户单击后退键

ExtendedPhoneApplicationPage询问MainViewModel（或实现InActivation的不同版本）现在应该开始什么动画

MainViewModel将正确的动画返回到视图

MVVM是否正确？如果没有，如何实现这一点？

编辑：

可能我上面写的不是很好的解决方案，我读到ViewModel应该只通过数据绑定和命令与View通信。我今天在想这个，我有了这个想法

在XAML中，应该是这样的：

<Navigation>
        <NavigationInTransition>
            <NavigationInTransition.ForwardTransitions>
                <ForwardTransition NavigateTo="page2.xaml">
                    <ForwardTransition.Animation>
                        <SlideTransitionAnimation Mode="ForwardIn"/>
                    </ForwardTransition.Animation>
                </ForwardTransition>
                <ForwardTransition NavigateTo="page3.xaml">
                    <ForwardTransition.Animation>
                        <TurnstyleTransitionAnimation Mode="ForwardIn"/>
                    </ForwardTransition.Animation>
                </ForwardTransition>
            </NavigationInTransition.ForwardTransitions>
        </NavigationInTransition>
        <BackKeyPressed IsPrevent="{Binding SomethingBool}" Command="{Binding BackKeyPressed}"/>
</Navigation>

---

在App.xaml中创建资源

  <Style x:Key="PageStyle" 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>

对于带有转换的页面 Style=“{StaticResource PageStyle}”