如何在WinRT XAML中使用HeaderTemplate绑定User Control的DependencyProperty？

Question

我有一个GridView，将我的ObservableCollection不同的类项绑定到我的Hub页面。 绑定不同类项到GridView并显示不同的项数据模板，标题模板。

我在Header Template中使用User Control。我的Header Template包括User Control和一些ComboBoxes。我想通过pageRoot对象的参数将页面根数据上下文集合绑定到Header Template中的ComboBox。

我创建了一个User Control并创建了一些DependencyProperty、ComboBox事件处理程序。但是无法将pageRoot DataContext集合绑定到User Control中的ComboBoxes :(

我的英语很差，对此感到抱歉；) 感谢您的回答...

我的HeaderDataTemplate：

<DataTemplate x:Key="OrganizationFixtureHeaderTemplate">
    <Grid Margin="6">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto"/>
            <ColumnDefinition Width="*"/>
        </Grid.ColumnDefinitions>

        <StackPanel Grid.Column="0">
            <TextBlock Text="{Binding Title}" Style="{StaticResource TitleTextStyle}"/>
        </StackPanel>

        <UserControls:UcCbOrganizationFixtureSelections  
            Grid.Column="1"
            RootElement="pageRoot"
            PageOrganizationSource="{Binding PageOrganization, ElementName=pageRoot}"
            />

    </Grid>
</DataTemplate>

我的用户控件代码：

<UserControl
    x:Class="Modern_UI.Common.UserControls.UcCbOrganizationFixtureSelections"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:Modern_UI.Common.UserControls"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d">

    <StackPanel Orientation="Horizontal">
        <ComboBox x:Name="cbOrgFixtureSeasons" 
                          ItemsSource="{Binding Path=DataContext.Seasons, ElementName=RootElement}"
                          SelectedValuePath="Id" 
                          DisplayMemberPath="Name"
                          SelectionChanged="CbOrgFixtureSeasons_OnSelectionChanged"
                          Width="Auto"
                          Height="Auto"
                         />
        <ComboBox x:Name="cbOrgFixtureStages" 
                          ItemsSource="{Binding Path=DataContext.FixtureStages, ElementName=RootElement}"
                          SelectedValuePath="Id" 
                          DisplayMemberPath="Name"
                          SelectionChanged="CbOrgFixtureStages_OnSelectionChanged"
                          Width="Auto"
                          Height="Auto"
                  />
        <ComboBox x:Name="cbOrgFixtureRounds" 
                     ItemsSource="{Binding Path=DataContext.FixtureRounds, ElementName=RootElement}"
                     SelectedValuePath="Id" 
                     DisplayMemberPath="Name"
                     SelectionChanged="CbOrgFixtureRounds_OnSelectionChanged"
                     Width="Auto"
                     Height="Auto"
                  />
    </StackPanel>
</UserControl>

用户控件代码后台:

namespace Modern_UI.Common.UserControls
{
    public sealed partial class UcCbOrganizationFixtureSelections : UserControl
    {  
        public DependencyProperty RootElementProperty = DependencyProperty.Register("RootElement",
                                                                                    typeof(string),
                                                                                    typeof(
                                                                                        UcCbOrganizationFixtureSelections
                                                                                        ),
                                                                                    null);


        public DependencyProperty PageOrganizationSourceProperty = DependencyProperty.Register("PageOrganizationSource",
                                                                                               typeof(Organization),
                                                                                               typeof(
                                                                                                   UcCbOrganizationFixtureSelections
                                                                                                   ),
                                                                                               null);

        public string RootElement
        {
            get { return this.GetValue(RootElementProperty) as string; }
            set { this.SetValue(RootElementProperty, value); }
        }

        public Organization PageOrganizationSource
        {
            get { return this.GetValue(PageOrganizationSourceProperty) as Organization; }
            set { this.SetValue(PageOrganizationSourceProperty, value); }
        }


        public UcCbOrganizationFixtureSelections()
        {
            this.InitializeComponent();
        }

        async private void CbOrgFixtureSeasons_OnSelectionChanged(object sender, SelectionChangedEventArgs e)
        {
          //loading root page parameter via "PageOrganizationSource" named DependencyProperty.
        }
}

- The Goat

Answer 1

我已经解决了我的代码问题，并添加了一些代码。

1- 绑定根页面DataContext的用户控件。因为用户控件在gridview模板内部。如果在datatemplate中的控件内部，则绑定datatemplate itemsources的默认数据上下文。我不想与itemsource数据上下文相关联，而是绑定rootpage数据上下文。 在DataTemplate中替换代码：

<DataTemplate x:Key="OrganizationFixtureHeaderTemplate">
    <Grid Margin="6">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto"/>
            <ColumnDefinition Width="*"/>
        </Grid.ColumnDefinitions>

        <StackPanel Grid.Column="0">
            <TextBlock Text="{Binding Title}" Style="{StaticResource TitleTextStyle}"/>
        </StackPanel>

        <UserControls:UcCbOrganizationFixtureSelections  
            Grid.Column="1"
            RootElement="pageRoot"
            DataContext="{Binding DataContext, ElementName=pageRoot}"     
            PageOrganizationSource="{Binding PageOrganization, ElementName=pageRoot}"
            />
    </Grid>
</DataTemplate> 

2- 我在用户控件的XAML代码中进行了替换。现在，用户控件的DataContext是rootPage DataContext。我可以将每个集合绑定到我的组合框中。

<UserControl
    x:Class="Lig_TV_Modern_UI.Common.UserControls.UcCbOrganizationFixtureSelections"
    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"
    mc:Ignorable="d">

    <StackPanel Orientation="Horizontal">
        <ComboBox x:Name="cbOrgFixtureSeasons" 
                          ItemsSource="{Binding Seasons}"
                          SelectedValuePath="Id" 
                          DisplayMemberPath="Name"
                          SelectionChanged="CbOrgFixtureSeasons_OnSelectionChanged"
                          Width="Auto"
                          Height="Auto"                             
                         />        
    </StackPanel>
</UserControl>

感谢您考虑这个问题。这个结构可以与每个元素通信，并且可以绑定每个集合，而无需使用datatemplate itemsource datacontext。如果需要控件的事件处理程序，则可以使用用户控件。

愉快编码的日子；）

- The Goat