为什么要使用FlowListView，底部会有这么多的空白

Question

为什么我要使用FlowListView，底部会有这么多的空白。 请查看我上传的图片。 帮帮我，谢谢

有我的代码：

 <Grid BackgroundColor="{StaticResource ColorEFEFEF}">
        <ScrollView>
            <Grid>

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

                <StackLayout Grid.Row="0" BackgroundColor="White" Padding="17,6">
                    <flv:FlowListView Grid.Row="0" FlowColumnCount="3"
                                      SeparatorVisibility="None"
                                      HasUnevenRows="True" 
                                      FlowItemsSource="{Binding Albums}">
                        <flv:FlowListView.FlowColumnTemplate>
                            <DataTemplate>
                                <templates:AllAlbumsTempalte></templates:AllAlbumsTempalte>
                            </DataTemplate>
                        </flv:FlowListView.FlowColumnTemplate>
                    </flv:FlowListView>
                </StackLayout>

                <StackLayout Grid.Row="1" Style="{StaticResource GridStyleSection}">
                    <Label FontSize="Small">
                        <Label.FormattedText>
                            <FormattedString>
                                <Span Text="当照片数量少于4张时，"></Span>
                                <Span Text="不会被搜索到" TextColor="Red"></Span>
                                <Span Text="。另外照片数量越多，"></Span>
                                <Span Text="搜索权重越高" TextColor="Red"></Span>
                                <Span Text="。"></Span>
                            </FormattedString>
                        </Label.FormattedText>
                    </Label>
                </StackLayout>

                <!--上传照片-->
                <StackLayout Grid.Row="2" Style="{StaticResource GridStyleSection}">
                    <StackLayout Orientation="Vertical" HorizontalOptions="Start">
                        <Label Text="上传图片" FontSize="Medium"></Label>

                        <Button x:Name="ButtonPhoto" Text="+" 
                                BorderWidth="1"
                                BorderColor="LightGray"
                                HeightRequest="115"
                                WidthRequest="115"
                                BackgroundColor="{StaticResource ColorFAFAFA}"
                                FontSize="60"
                                FontAttributes="None"
                                CornerRadius="3"
                                TextColor="{StaticResource ColorDFDFDF}"/>
                    </StackLayout>
                </StackLayout>
            </Grid>
        </ScrollView>
    </Grid>

显示后，底部还有很多空白。

点击下面的链接查看图片，谢谢： https://i.stack.imgur.com/JqSrC.png

enter image description here

templates：AllAlbumsTempalte代码在这里：

<?xml version="1.0" encoding="utf-8" ?>
<Grid xmlns="http://xamarin.com/schemas/2014/forms"
      xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
      xmlns:ffimageloading="clr-namespace:FFImageLoading.Forms;assembly=FFImageLoading.Forms"
      xmlns:ffimgtransform="clr-namespace:FFImageLoading.Transformations;assembly=FFImageLoading.Transformations"
      x:Class="Ransol.Springlove.App.Templates.AlbumTemplate"
      Padding="3,3,3,3">

    <Grid.RowDefinitions>
        <RowDefinition Height="*" />
    </Grid.RowDefinitions>
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="*" />
    </Grid.ColumnDefinitions>

    <Frame Padding="0" CornerRadius="3" HasShadow="True" BorderColor="Transparent" HeightRequest="115">
        <ffimageloading:CachedImage DownsampleToViewSize="true" 
                                    AbsoluteLayout.LayoutFlags="All" 
                                    IsOpaque="False"
                                    Source="{Binding SmallUrl}"  
                                    HeightRequest="115"
                                    DownsampleHeight="115"
                                    MinimumHeightRequest="115"
                                    DownsampleUseDipUnits="False"
                                    Aspect="AspectFill">
        </ffimageloading:CachedImage>
    </Frame>
    <Frame Padding="0" BackgroundColor="Transparent" CornerRadius="3">
        <StackLayout HorizontalOptions="End" VerticalOptions="Start" Padding="6,3" BackgroundColor="Silver" Opacity="0.6">
            <Label Text="&#xf00d;" HorizontalTextAlignment="Center" TextColor="White" FontSize="Medium">
                <Label.FontFamily>
                    <OnPlatform x:TypeArguments="x:String" Android="fa-solid-900.ttf#Font Awesome 5 Free" iOS="Font Awesome 5 Free" />
                </Label.FontFamily>
            </Label>
        </StackLayout>
    </Frame>
    <Frame Padding="0" BackgroundColor="Transparent" CornerRadius="3">
        <StackLayout x:Name="Delete" HorizontalOptions="End" VerticalOptions="Start" Padding="6,3">
            <Label Text="&#xf00d;" HorizontalTextAlignment="Center" TextColor="White" FontSize="Medium">
                <Label.FontFamily>
                    <OnPlatform x:TypeArguments="x:String" Android="fa-solid-900.ttf#Font Awesome 5 Free" iOS="Font Awesome 5 Free" />
                </Label.FontFamily>
            </Label>
        </StackLayout>
    </Frame>
</Grid>