Windows 8 系列 DataTemplateSelector_IValueConverter 随笔

除了对 DataTemplateSelector和IValueConverter的基本用法外，还主要是说明了两者结合调用资源的用法。

DataTemplateSelector：cs

public class TaskListDataTemplateSelector : DataTemplateSelector
    {

        /// <summary>
        /// 数据模板1
        /// </summary>
        public DataTemplate itemGridView1 { get; set; }

        /// <summary>
        /// 数据模板2
        /// </summary>
        public DataTemplate itemGridView2 { get; set; }


        protected override DataTemplate SelectTemplateCore(object item, DependencyObject container)
        {
           
            var i = item as Item;
            if (i != null)
            {
                if (i.Index % 2 == 0)
                {
                    return itemGridView1;
                }
                else
                {
                    return itemGridView2;
                }
            }
            return null;
        }
    }

IValueConverter:cs

public class DateTimeConvert : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, string language)
        {
            string output = string.Empty;
            DateTime time;
            if (DateTime.TryParse(value.ToString(), out time))
            {
                output = time.ToString("yyyy-MM-dd HH-mm");
            }
            return output;
        }

        public object ConvertBack(object value, Type targetType, object parameter, string language)
        {
            throw new NotImplementedException();
        }
    }

MainPage.xaml

<Page
    x:Class="Win8_DataBinding.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:Win8_DataBinding"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:common="using:Win8_DataBinding.Common"
    xmlns:convert="using:Win8_DataBinding.Convert"
    mc:Ignorable="d">


    <Page.Resources>
        <!--<CollectionViewSource x:Name="cvs"  IsSourceGrouped="True" ItemsPath="Items" />-->
        <!-- 数据源-->
        <CollectionViewSource x:Name="cvs1" IsSourceGrouped="true"  ItemsPath="Items" />
        <!-- 日前转换资源-->
        <convert:DateTimeConvert x:Key="DateTimeConvert" />
        <!-- 数据模板1-->
        <DataTemplate x:Key="itemGridView1">
            <StackPanel>
                <TextBlock Text='{Binding Title}' Foreground="Gray" FontSize="25" Margin="5" />
                <TextBlock Text='{Binding Title}' Foreground="Gray" FontSize="25" Margin="5" />
            </StackPanel>

        </DataTemplate>
        <!-- 数据模板2-->
        <DataTemplate x:Key="itemGridView2">
            <StackPanel>
                <TextBlock Text='{Binding Title}' Foreground="Gray" FontSize="25" Margin="5" />
                <TextBlock Text='{Binding DateTime, Converter={StaticResource DateTimeConvert}}' Foreground="Gray" FontSize="25" Margin="5" />
            </StackPanel>

        </DataTemplate>
        <!-- 模板转换资源 分别给资源1,2赋值-->
        <common:TaskListDataTemplateSelector x:Key="itemTemplate"
            itemGridView1="{StaticResource itemGridView1}"
            itemGridView2="{StaticResource itemGridView2}" ></common:TaskListDataTemplateSelector>
    </Page.Resources>
    
    <Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}">

        <SemanticZoom>
            <SemanticZoom.ZoomedInView>
                <!-- 指定ItemTemplateSelector的资源-->
                <GridView x:Name="gridView" 
                 ItemsSource="{Binding Source={StaticResource cvs1}}"  
                          SelectionMode="None"
                          ItemTemplateSelector="{StaticResource itemTemplate}">
                    <GridView.GroupStyle>
                        <GroupStyle>
                            <GroupStyle.HeaderTemplate>
                                <DataTemplate>
                                    <TextBlock Text='{Binding Key}' Foreground="Gray" FontSize="25" Margin="5" />
                                    
                                </DataTemplate>
                            </GroupStyle.HeaderTemplate>
                        </GroupStyle>
                    </GridView.GroupStyle>
                </GridView>
            </SemanticZoom.ZoomedInView>
            <SemanticZoom.ZoomedOutView>
                <GridView x:Name="outView" >
                    <GridView.ItemTemplate>
                        <DataTemplate>
                            <TextBlock Text='{Binding Group.Key}' Foreground="Gray" FontSize="25" Margin="5" />
                        </DataTemplate>
                    </GridView.ItemTemplate>
                </GridView>
            </SemanticZoom.ZoomedOutView>
        </SemanticZoom>
    </Grid>
</Page>