I'm search How to show all my Item, but for that I need to make automatic Heigh of My user control I wish the aparence as the same of :
  <Grid>
      <Grid.RowDefinitions>
        <RowDefinition Height="*"/>
        <RowDefinition Height="*"/>
        <RowDefinition Height="*"/>
        .
        .
        .
        <RowDefinition Height="*"/>
        <RowDefinition Height="*"/>
        <RowDefinition Height="*"/>
     </Grid.RowDefinitions >
     <control:Plat Grid.Row="1"></control:Plat>
     <control:Plat Grid.Row="2"></control:Plat>
     <control:Plat Grid.Row="3"></control:Plat>
     .
     .
     .
     <control:Plat Grid.Row="n-2"></control:Plat>
     <control:Plat Grid.Row="n-1"></control:Plat>
     <control:Plat Grid.Row="n"></control:Plat>
  </Grid>
With this code :
<Grid Grid.Row="0">
<Grid.ColumnDefinitions>
    <ColumnDefinition />
    <ColumnDefinition />
    <ColumnDefinition />
</Grid.ColumnDefinitions>
<DockPanel>
    <ItemsControl x:Name="RepasMatin">
        <ItemsControl.ItemTemplate>
            <DataTemplate DataType="classes:C_T_plat">
                <control:Plat ></control:Plat>
            </DataTemplate>
        </ItemsControl.ItemTemplate>
    </ItemsControl>
</DockPanel>
<materialDesign:PackIcon Kind="Build" Grid.Column="2" HorizontalAlignment="Right" Cursor="Hand"/>
Best Regards
