Question

在ContentPage中，我在ListView中有一个“房间”列表。当我点击其中一个时，它应该导航到另一个ContentPage以及房间的详细信息。调用新页面的ViewModel上的OnNavigatedTo（）（显然没有错误），但页面没有显示。它保留在页面中的房间列表。我用Visual Studio 2015用Android（模拟器和手机）测试它。

这里是列表页面的XAML：

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:prism="clr-namespace:Prism.Mvvm;assembly=Prism.Forms"
             xmlns:views="clr-namespace:StudentRooms.Views;assembly=StudentRooms"
             prism:ViewModelLocator.AutowireViewModel="True"
             x:Class="StudentRooms.Views.RoomsList">

  <StackLayout Orientation="Vertical">
    <ListView ItemsSource="{Binding Rooms}"
              >
      <ListView.ItemTemplate>
        <DataTemplate>
          <ViewCell>
            <StackLayout Orientation="Horizontal" Spacing="10">

              <StackLayout.GestureRecognizers>
                <TapGestureRecognizer CommandParameter="{Binding Id}" 
                                      Command="{Binding BindingContext.RoomSelected, Source={views:RoomsList}}">
                </TapGestureRecognizer>
              </StackLayout.GestureRecognizers>

              <Label Text="{Binding Name}" FontAttributes="Bold"/>
              <Label Text="{Binding Description}"></Label>
              <ProgressBar Progress="{Binding Occupancy}"/>
            </StackLayout>
          </ViewCell>
        </DataTemplate>
      </ListView.ItemTemplate>
    </ListView>  
  </StackLayout>

</ContentPage>

这是ViewModel的片段：

public RoomsListViewModel(INavigationService navigationService)
{
    _navigationService = navigationService;

    RoomSelected = new DelegateCommand<object>(NavigateToSelectedRoom);
}

private void NavigateToSelectedRoom(object id)
{
    //var navParams = new NavigationParameters
    //{
    //    { "RoomId", id }
    //};

    //_navigationService.NavigateAsync("RoomDetail", navParams);

    _navigationService.NavigateAsync("RoomDetail");
}

详情页面：

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:prism="clr-namespace:Prism.Mvvm;assembly=Prism.Forms"
             prism:ViewModelLocator.AutowireViewModel="True"
             x:Class="StudentRooms.Views.RoomDetail">

  <StackLayout>
    <Label Text="AAA"></Label>
  </StackLayout>
</ContentPage>

ViewModel的片段：

public void OnNavigatedTo(NavigationParameters parameters)
{
    // on Debug I enter in this method!
}

Answer 1

确保在App.cs / App.xaml.cs文件中注册要导航的页面。

Xamarin形成棱镜 - 从网格导航到内容页面。页面未显示

1 个答案: