c# - Xamarin 中项目列表的 ItemTemplate

Question

我有一个 ListView与 ItemTemplate .对于我 ItemSource 中的每个项目，我想遍历项目中的一个属性并在我的 ViewCell 中创建一个部分.
所以每一项都是 Download :

public class Download
{
    public string Title { get; set; }

    public IEnumerable<SectionDownload> SectionDownloads { get; set; }
}

SectionDownload看起来像这样:

public class SectionDownload
{
    public long TotalBytes { get; set; }

    public long DownloadedBytes { get; set; }

    public int PercentDownloaded { get => (int)((DownloadedBytes / TotalBytes) * 100); }
}

还有我的 ListView ，其中 Downloads是 ObservableCollection<Download>在我的 View 模型中:

<ListView x:Name="DownloadsListView" SelectionMode="None" ItemsSource="{Binding Downloads}">
    <ListView.ItemTemplate>
        <DataTemplate>
            <StackLayout Padding="10">
                <Label Text="{Binding Title}"
                            d:Text="{Binding .}"
                            LineBreakMode="NoWrap"
                            Style="{DynamicResource ListItemTextStyle}"
                            FontSize="16" />
                <!-- Here I would like each SectionDownload to display the percentage downloaded -->
            </StackLayout>
        </DataTemplate>
    </ListView.ItemTemplate>
</ListView>

Answer 1

您可以像这样显示部分。

<ListView x:Name="DownloadsListView" SelectionMode="None" ItemsSource="{Binding Downloads}">
<ListView.ItemTemplate>
    <DataTemplate>
        <StackLayout Padding="10">
            <Label Text="{Binding Title}"
                        d:Text="{Binding .}"
                        LineBreakMode="NoWrap"
                        Style="{DynamicResource ListItemTextStyle}"
                        FontSize="16" />
            <StackLayout BindableLayout.ItemsSource="{Binding SectionDownloads}">
                <BindableLayout.ItemTemplate>
                    <DataTemplate>
                        <ProgressBar Progress="{Binding PercentDownloaded}" />
                    </DataTemplate>
                </BindableLayout.ItemTemplate>
            </StackLayout>
        </StackLayout>
    </DataTemplate>
</ListView.ItemTemplate>

PercentDownloaded 的值应该是 0 到 1 范围内的两倍，并且您还必须对 SectionDownload 类实现 INotifyPropertyChange 以实时更新进度。