Visibility.Collapse ne fonctionne pas dans WPF

Question

Visibility.Collapse ne fonctionne pas dans mon cas. ci-dessous est le XAML. Si j'essaie de cacher les lblCountry et cmbCountry, un espace blanc est affiché entre les champs zip et pratique. Il n'y a pas d'option pour masquer une ligne entière d'un Grid.

<Grid> 
    <Canvas Name="canDemographic" > 

    </Canvas> 
    <Grid HorizontalAlignment="Center" VerticalAlignment="Center"> 
     <Grid.ColumnDefinitions> 
      <ColumnDefinition Width="auto"/> 
      <ColumnDefinition Width="auto"/> 
     </Grid.ColumnDefinitions> 
     <Grid.RowDefinitions> 
      <RowDefinition Height="40"/> 
      <RowDefinition Height="40" /> 
      <RowDefinition Height="40" /> 
      <RowDefinition Height="40" /> 
      <RowDefinition Height="40" /> 
      <RowDefinition Height="40"/> 
      <RowDefinition Height="40"/> 
      <RowDefinition Height="40"/> 
      <RowDefinition Height="40"/> 
      <RowDefinition Height="40"/> 
      <RowDefinition Height="40"/> 
      <RowDefinition Height="40"/> 
      <RowDefinition Height="40"/> 
     </Grid.RowDefinitions> 
     <TextBlock Width="800" Height="50" Grid.Column="0" Grid.Row="1" Grid.ColumnSpan="2" VerticalAlignment="Center" HorizontalAlignment="Center" FontFamily="Arial" FontSize="30" FontWeight="Bold" Visibility="Collapsed"> 
    Please review or enter your user information details: 
     </TextBlock> 
     <TextBlock Width="200" Height="30" Grid.Column="0" Grid.Row="2" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold"> 
    *First Name: 
     </TextBlock> 
     <TextBlock Width="200" Height="30" Grid.Column="0" Grid.Row="3" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" Text=" Middle Name:"></TextBlock> 
     <TextBlock Width="200" Height="30" Grid.Column="0" Grid.Row="4" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold"> 
    *Last Name: 
     </TextBlock> 
     <TextBlock Name="tbEmail" Width="200" Height="30" Grid.Column="0" Grid.Row="12" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold"> 
    *Email Address: 
     </TextBlock> 
     <TextBlock Width="200" Height="30" Grid.Column="0" Grid.Row="5" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold"> 
    *Address1: 
     </TextBlock> 
     <TextBlock Width="200" Height="30" Grid.Column="0" Grid.Row="6" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" Text=" Address2:"></TextBlock> 
     <TextBlock Width="200" Height="30" Grid.Column="0" Grid.Row="7" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold"> 
    *City: 
     </TextBlock> 
     <TextBlock Width="200" Height="30" Grid.Column="0" Grid.Row="8" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold"> 
    *State: 
     </TextBlock> 
     <TextBlock Width="200" Height="30" Grid.Column="0" Grid.Row="9" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold"> 
    *Zip: 
     </TextBlock> 
     <TextBlock Name="lblCountry" Width="200" Grid.Column="0" Grid.ColumnSpan="2" Grid.Row="10" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" Text=" *Country:" Visibility="Collapsed"="></TextBlock> 
     <TextBlock Width="200" Height="30" Grid.Column="0" Grid.Row="11" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" Text=" Practice/Affiliation:"></TextBlock> 

     <!-- Input fields --> 
     <TextBox Name="txtFirstName" Width="200" Height="30" 
     Grid.Column="1" Grid.Row="2" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" MaxLength="20" TextChanged="txtFirstName_TextChanged" IsEnabled="True" /> 
     <TextBox Name="txtMiddleName" Width="200" Height="30" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" 
     Grid.Column="1" Grid.Row="3" MaxLength="10" IsEnabled="True" /> 
     <TextBox Name="txtLastName" Width="200" Height="30" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" 
     Grid.Column="1" Grid.Row="4" MaxLength="20" TextChanged="txtLastName_TextChanged" /> 
     <TextBox Name="txtEmail" Width="200" Height="30" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" 
     Grid.Column="1" Grid.Row="12" MaxLength="100"/> 
     <TextBox Name="txtAddress1" Width="200" Height="30" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" 
     Grid.Column="1" Grid.Row="5" MaxLength="100" TextChanged="txtAddress1_TextChanged" /> 
     <TextBox Name="txtAddress2" Width="200" Height="30" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" 
     Grid.Column="1" Grid.Row="6" MaxLength="100"/> 
     <TextBox Name="txtCity" Width="200" Height="30" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" 
     Grid.Column="1" Grid.Row="7" MaxLength="50" TextChanged="txtCity_TextChanged" /> 
     <TextBox Name="txtState" Width="200" Height="30" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" 
     Grid.Column="1" Grid.Row="8" MaxLength="50" TextChanged="txtState_TextChanged" /> 
     <TextBox Name="txtZip" Width="200" Height="30" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" 
     Grid.Column="1" Grid.Row="9" MaxLength="50" TextChanged="txtZip_TextChanged" /> 
     <ComboBox Name="cmbCountry" Width="200" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" 
     Grid.Column="0" Grid.Row="10" Grid.ColumnSpan="2" SelectionChanged="cmbCountry_SelectionChanged" ItemsSource="{Binding}" Visibility="Collapsed" /> 
     <TextBox Name="txtPractice" Width="200" Height="30" VerticalAlignment="Center" HorizontalAlignment="Left" FontFamily="Arial" FontSize="18" FontWeight="Bold" 
     Grid.Column="1" Grid.Row="11" MaxLength="50"/> 
    </Grid> 
    <Button Name="btnExit" Height="30" VerticalAlignment="Bottom" Width="100" HorizontalAlignment="Left" Margin="21,0,0,12" BorderThickness="1" FontFamily="arial" Background="LightGray" FontSize="12pt" FontWeight="Bold" Click="btnExit_Click">Back</Button> 
    <Button Name="btnNext" Height="30" VerticalAlignment="Bottom" Width="100" HorizontalAlignment="Right" Margin="0,0,21,12" BorderThickness="1" FontFamily="arial" Background="LightGray" FontSize="12pt" FontWeight="Bold" Click="btnNext_Click" IsEnabled="False" >Next</Button> 
</Grid> 
    </ScrollViewer> 

Answer 1

Je pense que ce qui se passe parce que vous définissez explicitement la hauteur de vos lignes (à 40), de sorte que même lorsque le contenu des lignes sont effondrées il faut l'espace de 40 Essayez définir le Height de la ligne à Auto.