LehrerApp/LehrerApp.Desktop/Views/ClassTeacher/ClassTeacherAbsencesView.axaml

<UserControl xmlns="https://github.com/avaloniaui"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:vm="clr-namespace:LehrerApp.Desktop.ViewModels.ClassTeacher"
             x:Class="LehrerApp.Desktop.Views.ClassTeacher.ClassTeacherAbsencesView"
             x:DataType="vm:ClassTeacherDetailsViewModel">

  <UserControl.Styles>
    <!-- Siehe Styles/SemanticBrushes.axaml: Farben per DynamicResource, damit der Theme-Wechsel
         sie live austauscht; die Statusfarbe je Zeile kommt als Style-Klasse aus dem ViewModel. -->
    <Style Selector="Border.filterCard">
      <Setter Property="Background" Value="{DynamicResource AppCardBackgroundBrush}"/>
      <Setter Property="BorderBrush" Value="{DynamicResource AppCardBorderBrush}"/>
      <Setter Property="BorderThickness" Value="1"/>
      <Setter Property="CornerRadius" Value="8"/>
      <Setter Property="Padding" Value="10"/>
    </Style>
    <Style Selector="TextBlock.status">
      <Setter Property="Foreground" Value="{DynamicResource AppStatusOkBrush}"/>
    </Style>
    <Style Selector="TextBlock.status.info">
      <Setter Property="Foreground" Value="{DynamicResource AppStatusInfoBrush}"/>
    </Style>
    <Style Selector="TextBlock.status.warning">
      <Setter Property="Foreground" Value="{DynamicResource AppStatusWarningBrush}"/>
    </Style>
    <Style Selector="TextBlock.status.danger">
      <Setter Property="Foreground" Value="{DynamicResource AppStatusDangerBrush}"/>
    </Style>
  </UserControl.Styles>

  <Grid RowDefinitions="Auto,Auto,*,Auto" Margin="16" RowSpacing="10">
    <Grid Grid.Row="0" ColumnDefinitions="*,Auto">
      <StackPanel>
        <TextBlock Text="Fehlzeiten" FontSize="22" FontWeight="SemiBold"/>
        <TextBlock Text="Pro Schüler*in und Tag über alle Fächer zusammengefasst" FontSize="12" Opacity="0.55"/>
      </StackPanel>
      <Button Grid.Column="1" Content="↻  Aus WebUntis aktualisieren" Command="{Binding RefreshCommand}"
              IsEnabled="{Binding !Busy}" Background="Transparent" Foreground="{DynamicResource AppAccentTextBrush}" VerticalAlignment="Center"/>
    </Grid>

    <Border Grid.Row="1" Classes="filterCard">
      <Grid RowDefinitions="Auto,Auto" RowSpacing="8">
        <Grid Grid.Row="0" ColumnDefinitions="155,Auto,*,Auto,*" ColumnSpacing="8">
          <ComboBox Grid.Column="0" SelectedIndex="{Binding QuickRangeIndex, Mode=TwoWay}">
            <ComboBoxItem Content="Heute"/><ComboBoxItem Content="Letzte 7 Tage"/><ComboBoxItem Content="Letzte 30 Tage"/>
          </ComboBox>
          <TextBlock Grid.Column="1" Text="von" VerticalAlignment="Center" Opacity="0.6"/>
          <CalendarDatePicker Grid.Column="2" SelectedDate="{Binding StartDate}" HorizontalAlignment="Stretch"/>
          <TextBlock Grid.Column="3" Text="bis" VerticalAlignment="Center" Opacity="0.6"/>
          <CalendarDatePicker Grid.Column="4" SelectedDate="{Binding EndDate}" HorizontalAlignment="Stretch"/>
        </Grid>
        <Grid Grid.Row="1" ColumnDefinitions="*,Auto,Auto" ColumnSpacing="8">
          <TextBox Grid.Column="0" Text="{Binding StudentFilter, Mode=TwoWay}" PlaceholderText="Schüler*in filtern…"/>
          <Button Grid.Column="1" Content="Anzeigen" Command="{Binding ApplyFilterCommand}" IsEnabled="{Binding !Busy}"/>
          <Button Grid.Column="2" Content="Filter löschen" Command="{Binding ClearStudentFilterCommand}"
                  IsVisible="{Binding StudentFilter, Converter={x:Static StringConverters.IsNotNullOrEmpty}}"/>
        </Grid>
      </Grid>
    </Border>

    <Grid Grid.Row="2">
      <DataGrid ItemsSource="{Binding AbsenceEntries}" AutoGenerateColumns="False" IsReadOnly="True"
                GridLinesVisibility="Horizontal" BorderBrush="{DynamicResource AppCardBorderBrush}" BorderThickness="1"
                CanUserResizeColumns="True" CanUserSortColumns="True" RowHeight="48">
        <DataGrid.Columns>
          <DataGridTextColumn Header="Datum" Binding="{Binding DateLabel}" Width="105"/>
          <DataGridTextColumn Header="Schüler*in" Binding="{Binding StudentDisplayName}" Width="1.3*"/>
          <DataGridTemplateColumn Header="Art" Width="1.15*">
            <DataGridTemplateColumn.CellTemplate>
              <DataTemplate x:DataType="vm:ClassAbsenceDaySummaryRow">
                <TextBlock Text="{Binding KindLabel}" Classes="status"
                           Classes.warning="{Binding IsWarningStatus}"
                           Classes.danger="{Binding IsDangerStatus}" VerticalAlignment="Center"/>
              </DataTemplate>
            </DataGridTemplateColumn.CellTemplate>
          </DataGridTemplateColumn>
          <DataGridTemplateColumn Header="Status" Width="1*">
            <DataGridTemplateColumn.CellTemplate>
              <DataTemplate x:DataType="vm:ClassAbsenceDaySummaryRow">
                <Border Background="{DynamicResource AppChipBackgroundBrush}" CornerRadius="5"
                        Padding="7,3" HorizontalAlignment="Left">
                  <TextBlock Text="{Binding FriendlyStatusLabel}" Classes="status"
                             Classes.warning="{Binding IsWarningStatus}"
                             Classes.danger="{Binding IsDangerStatus}" FontSize="11"/>
                </Border>
              </DataTemplate>
            </DataGridTemplateColumn.CellTemplate>
          </DataGridTemplateColumn>
          <DataGridTextColumn Header="Fächer" Binding="{Binding SubjectsLabel}" Width="1.2*"/>
          <DataGridTextColumn Header="Stunden" Binding="{Binding PeriodsLabel}" Width="0.75*"/>
          <DataGridTextColumn Header="Grund / Notiz" Binding="{Binding DetailLabel}" Width="2*"/>
        </DataGrid.Columns>
      </DataGrid>
      <StackPanel IsVisible="{Binding !HasAbsenceEntries}" HorizontalAlignment="Center" VerticalAlignment="Center" Spacing="5">
        <TextBlock Text="Keine Fehlzeiten im gewählten Zeitraum" FontWeight="SemiBold"/>
        <TextBlock Text="Passe Zeitraum oder Schülerfilter an." FontSize="12" Opacity="0.55"/>
      </StackPanel>
    </Grid>
    <TextBlock Grid.Row="3" Text="{Binding Status}" FontSize="11" Opacity="0.6"/>
  </Grid>
</UserControl>