Update app.py

app.py

@@ -91,6 +91,15 @@ app.layout = dbc.Container([
         dbc.Col([
             html.Div(style={"height": "20px"}),  # Small gap
             html.Div(id="loading-output"),  # Text status box
+            html.Div([  # New row for progress indicator
+                dcc.Loading(
+                    id="loading-indicator",
+                    type="dot",
+                    children=[html.Div(style={"height": "50px"})]  # Increased height for visibility
+                ),
+            ], className="my-3"),  # Add margin for separation
+            html.Div(id='matrix-preview', className="border p-3 mb-3"),
+            html.Div(id="loading-output"),  # Text status box
             dcc.Loading(
                 id="loading-indicator",
                 type="dot",
@@ -176,7 +185,19 @@ def remove_file(n_clicks, existing_files):
     removed_file = triggered_id.split('"index":')[1].split('}')[0].strip('"')
     
     uploaded_files.pop(removed_file, None)
-    return [file for file in existing_files if file['props']['children'][1]['children'] != removed_file]
+    
+    # Updated file filtering logic
+    return [
+        file for file in existing_files 
+        if isinstance(file, dict) and 
+           'props' in file and 
+           'children' in file['props'] and 
+           isinstance(file['props']['children'], list) and 
+           len(file['props']['children']) > 1 and 
+           isinstance(file['props']['children'][1], dict) and 
+           'children' in file['props']['children'][1] and 
+           file['props']['children'][1]['children'] != removed_file
+    ]
     
 def generate_matrix_with_gpt(matrix_type, file_contents):
     prompt = f"""Generate a {matrix_type} based on the following project artifacts: