I prefer to take an approach using dialogs that doesn't lock up the application, and moves away from the more traditional Win32 Dialog.
Example

Input Dialog Hidden

In this example I use a simplified version of the MVVM based solution I am using for my applications. It may not be pretty, but should give you a solid idea on the basics behind it.
The XAML:
<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<Grid>
<StackPanel>
<Button Content="Cool Button" x:Name="CoolButton" Click="CoolButton_Click"/>
<ListBox x:Name="MyListBox"/>
</StackPanel>
<!-- It's important that this is in the end of the XAML as it needs to be on top of everything else! -->
<Grid x:Name="InputBox" Visibility="Collapsed">
<Grid Background="Black" Opacity="0.5"/>
<Border
MinWidth="250"
Background="Orange"
BorderBrush="Black"
BorderThickness="1"
CornerRadius="0,55,0,55"
HorizontalAlignment="Center"
VerticalAlignment="Center">
<StackPanel>
<TextBlock Margin="5" Text="Input Box:" FontWeight="Bold" FontFamily="Cambria" />
<TextBox MinWidth="150" HorizontalAlignment="Center" VerticalAlignment="Center" x:Name="InputTextBox"/>
<StackPanel Orientation="Horizontal" HorizontalAlignment="Center">
<Button x:Name="YesButton" Margin="5" Content="Yes" Background="{x:Null}" Click="YesButton_Click"/>
<Button x:Name="NoButton" Margin="5" Content="No" Background="{x:Null}" Click="NoButton_Click" />
</StackPanel>
</StackPanel>
</Border>
</Grid>
</Grid>
</Window>
It's very easy to show this dialog as you only need to set the Visibility of the InputBox
grid to visible. You then simply handle the Yes / No buttons and get the Input text from the TextBox.
So instead of using code that requires ShowDialog()
, you simply set the Visibility
option to Visible
. There are still some things to do in this example that we will handle in code-behind, like for example clearing the InputText box after handling the Yes/No Button clicks.
The code-behind:
namespace WpfApplication1
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private void CoolButton_Click(object sender, RoutedEventArgs e)
{
// CoolButton Clicked! Let's show our InputBox.
InputBox.Visibility = System.Windows.Visibility.Visible;
}
private void YesButton_Click(object sender, RoutedEventArgs e)
{
// YesButton Clicked! Let's hide our InputBox and handle the input text.
InputBox.Visibility = System.Windows.Visibility.Collapsed;
// Do something with the Input
String input = InputTextBox.Text;
MyListBox.Items.Add(input); // Add Input to our ListBox.
// Clear InputBox.
InputTextBox.Text = String.Empty;
}
private void NoButton_Click(object sender, RoutedEventArgs e)
{
// NoButton Clicked! Let's hide our InputBox.
InputBox.Visibility = System.Windows.Visibility.Collapsed;
// Clear InputBox.
InputTextBox.Text = String.Empty;
}
}
}
The code-behind could easily be done using a Dependency, or as ViewModel logic in this case, but for simplicity I kept it in the code-behind.