diff --git a/Torch/Views/PropertyGrid.xaml b/Torch/Views/PropertyGrid.xaml
index 273c84f..78b24d5 100644
--- a/Torch/Views/PropertyGrid.xaml
+++ b/Torch/Views/PropertyGrid.xaml
@@ -17,7 +17,7 @@
                 <ColumnDefinition/>
             </Grid.ColumnDefinitions>
             <TextBlock Grid.Column="0" Text="Filter: " Margin="3"/>
-            <TextBox Grid.Column="1" Margin="3" TextChanged="UpdateFilter"/>
+            <TextBox Name="TbFilter" Grid.Column="1" Margin="3" TextChanged="UpdateFilter" IsEnabled="False"/>
         </Grid>
         <ScrollViewer Grid.Row="1" x:Name="ScrollViewer"/>
         <TextBlock x:Name="TbDescription" Grid.Row="2" MinHeight="18"/>
diff --git a/Torch/Views/PropertyGrid.xaml.cs b/Torch/Views/PropertyGrid.xaml.cs
index 4d44340..9e0bd39 100644
--- a/Torch/Views/PropertyGrid.xaml.cs
+++ b/Torch/Views/PropertyGrid.xaml.cs
@@ -49,12 +49,14 @@ namespace Torch.Views
             if (e.NewValue == null)
             {
                 ScrollViewer.Content = null;
+                TbFilter.IsEnabled = false;
                 return;
             }
 
             var content = GenerateForType(e.NewValue.GetType());
             content.DataContext = e.NewValue;
             ScrollViewer.Content = content;
+            TbFilter.IsEnabled = true;
         }
 
         public Grid GenerateForType(Type t)
@@ -274,6 +276,8 @@ namespace Torch.Views
         {
             var filterText = ((TextBox)sender).Text;
             var grid = (Grid)ScrollViewer.Content;
+            if (grid == null)
+                return;
             foreach (var child in grid.Children)
             {
                 if (!(child is TextBlock block))