Update app.py

app.py

@@ -269,7 +269,7 @@ if 'selected_file' not in st.session_state:
     st.session_state.selected_file = None
 
 # Check if a new row is selected
-if selected_indices:
+if selected_indices and not selected_indices.empty:
     selected_index = list(selected_indices.keys())[0]
     selected_file = txt_files_df.iloc[selected_index]['File Name']
     
@@ -284,5 +284,7 @@ if st.session_state.selected_file:
     if st.button(f"Process {st.session_state.selected_file}"):
         file_path = txt_files_df[txt_files_df['File Name'] == st.session_state.selected_file]['Full Path'].iloc[0]
         process_file(file_path)
+else:
+    st.write("Please select a file to process.")
 
 st.markdown("For more information and updates, visit our [help page](https://huggingface.co/awacke1).")