Xamarin.Forms ListView在滚动后更改集合之前在Android中呈现错误

Question

If I simply modify the ListView's data without scrolling, everything displays correctly:

https://gfycat.com/illustriousnastyconey

However, if I scroll before changing the data, everything looks broken after the data changes:

https://gfycat.com/abandonedvelvetyaoudad

Here is my ListView XAML

<ListView ItemsSource="{Binding network.Predictions}" x:Name="ShowsList" IsGroupingEnabled="True" HasUnevenRows="True" ItemTapped="ShowsList_ItemTapped">
        <ListView.GroupHeaderTemplate>
            <DataTemplate>
                <ViewCell Height="25">
                    <Grid BackgroundColor="#CC778899">
                        <Label Text="{Binding Category}" FontSize="Small" TextColor="White" VerticalOptions="Center" Margin="5,0,0,0"/>
                    </Grid>                        
                </ViewCell>
            </DataTemplate>
        </ListView.GroupHeaderTemplate>

        <ListView.ItemTemplate>
            <DataTemplate>
                <ViewCell>
                    <Grid BackgroundColor="White">
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="*"/>
                            <ColumnDefinition Width="Auto"/>
                        </Grid.ColumnDefinitions>

                        <Grid.RowDefinitions>
                            <RowDefinition Height="Auto"/>
                            <RowDefinition Height="Auto"/>
                        </Grid.RowDefinitions>

                        <Label Text="{Binding Name}" FontSize="Medium" Margin="5"/>
                        <Label Grid.Column="1" Text="{Binding Status}" FontSize="Small" TextColor="{Binding StatusIndex, Converter={StaticResource StatusColor}}" Margin="5" VerticalOptions="Center/>
                    </Grid>

                </ViewCell>                    
            </DataTemplate>
        </ListView.ItemTemplate>
    </ListView>

Also, after this happens, if I scroll so that the messed up elements go off screen, and then scroll back, those elements appear just fine. It does appear to be allocating the space correctly, and they appear correctly after scrolling, so it's not reading the data incorrectly or anything like that, it's just not displaying correctly.

I had an idea and changed the background color of the listview to red to see if maybe the text was rendering as white, but nope, those missing elements are fully transparent. The correct elements all have a background color, but the missing elements just showed as red.

Answer 1

它似乎是listview的错误，此问题存在于3.6的初始版本中，并且已在3.6.0.344457中进行了修复，许多开发人员都遇到此问题，如果您有类似的问题，请查看： https://github.com。 com / xamarin / Xamarin.Forms / pull / 6390以及最快速，最轻松的解决方法是将Xamarin.Forms版本回滚