ListView WPF中的项目分组。

I have a ListView where I want to group the items based on a field of the item object. Below is the code I have:

我有一个ListView，我想在其中基于项对象的字段对项进行分组。下面是我的代码:

<ListView ItemsSource="{x:Bind MyVM.CollectionOfClassA, Mode=OneWay}"
    <ListView.GroupStyle>
        <GroupStyle>
            <GroupStyle.HeaderTemplate>
                <DataTemplate>
                    <TextBlock FontSize="15" FontWeight="Bold" Text="{Binding DateTimePropertyOfClassA}"/>
                </DataTemplate>
            </GroupStyle.HeaderTemplate>
        </GroupStyle>
    </ListView.GroupStyle>
</ListView>

Is there something I am missing? I want to group the items based on the DateTime property of ClassA objects. Also, if there is no item for any particular day, I would still like to show that date with empty list under that group (for that day). How can I achieve it?

有什么东西我遗漏了吗?我想基于ClassA对象的DateTime属性对项目进行分组。另外，如果没有特定日期的项目，我仍然希望在该组(当天)下显示空列表的日期。我怎样才能做到呢?

Edit: I am not able to use CollectionViewSource since my VM contains the collection of ClassA object (which is bound as item source to the listview) and I want to group the items based on one property of those ClassA objects. I am sure there is something I am missing out on. But I am not able to figure it out.

编辑:我不能使用CollectionViewSource，因为我的VM包含ClassA对象的集合(它作为项目源绑定到listview)，我想基于这些ClassA对象的一个属性对项目进行分组。我肯定我错过了一些东西。但是我不知道。

2 个解决方案

#1

I suggest creating a collection in the ViewModel IObservableCollection<ClassA> Properties (or whatever name), add it in the MainWindow class and then simply bind it in the ListView.

我建议在ViewModel IObservableCollection 属性(或其他名称)中创建一个集合，在MainWindow类中添加它，然后在ListView中绑定它。

<ListView ItemsSource="{Binding Path=Properties}">

#2

Here is the solution for anyone looking for it (thanks to the WPF masters out there https://social.msdn.microsoft.com/Forums/windowsapps/en-US/812ed260-e113-4a8b-9322-226ed56ac90c/grouping-of-items-in-listview-wpf?forum=wpdevelop&prof=required):

以下是任何寻找它的人的解决方案(感谢WPF的高手，https://social.msdn.microsoft.com/forums/windowsapps/en - us/812ed260 -e113- 4a82b - 226ed56ac90c/grouping-listview-wpf?

public class ClassA
{
    public DateTime DateTimePropertyOfClassA { get; set; }
}

public class MyVM
{
    public MyVM()
    {
        //return a grouped collection:
        Grouped = from x in CollectionOfClassA group x by x.DateTimePropertyOfClassA into grp orderby grp.Key select grp;
    }

    public IList<ClassA> CollectionOfClassA { get; set; } = new List<ClassA>()
    {
            new ClassA(){ DateTimePropertyOfClassA = DateTime.Parse("2016-01-01")},
            new ClassA(){ DateTimePropertyOfClassA = DateTime.Parse("2016-03-01")},
            new ClassA(){ DateTimePropertyOfClassA = DateTime.Parse("2016-03-01")},
            new ClassA(){ DateTimePropertyOfClassA = DateTime.Parse("2016-03-01")},
            new ClassA(){ DateTimePropertyOfClassA = DateTime.Parse("2016-03-01")},
            new ClassA(){ DateTimePropertyOfClassA =DateTime.Parse("2016-06-01")}
    };

    public IEnumerable<object> Grouped { get; }
}

Xaml:

<Page.Resources>
        <CollectionViewSource x:Name="cvs"
                              IsSourceGrouped="True"
                              Source="{x:Bind MyVM.Grouped, Mode=OneWay}"/>
</Page.Resources>

<StackPanel Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
    <ListView ItemsSource="{Binding Source={StaticResource cvs}}">
        <ListView.GroupStyle>
            <GroupStyle>
                <GroupStyle.HeaderTemplate>
                    <DataTemplate>
                        <TextBlock FontSize="15" FontWeight="Bold" Text="{Binding Key}"/>
                    </DataTemplate>
                </GroupStyle.HeaderTemplate>
            </GroupStyle>
        </ListView.GroupStyle>
    </ListView>
</StackPanel>

#1