improve loading experience

app.py

@@ -13,6 +13,7 @@ example_indexes = {
     "IONIQ 2024": "./iconiq_report_index",
     "Uber 10k 2021": "./uber_index",
 }
+DEFAULT_INDEX = "IONIQ 2024"
 
 device = "cpu"
 if torch.cuda.is_available():
@@ -42,7 +43,7 @@ class IndexManager:
     def __init__(self):
         self.current_index = None
         # Initialize with default index
-        self.load_index(example_indexes["IONIQ 2024"])
+        self.load_index(example_indexes[DEFAULT_INDEX])
     
     def load_index(self, index_path):
         storage_context = StorageContext.from_defaults(persist_dir=index_path)
@@ -218,20 +219,23 @@ Processing will take a few minutes when creating a new index, depending on the s
             )
     
     # Event handlers
-    def load_existing_index(index_name):
+    def load_existing_index(index_name, progress=gr.Progress()):
         if index_name:
             try:
-                index_manager.load_index(example_indexes[index_name])
-                return f"Loaded index: {index_name}"
+                progress(0, desc="Loading index...")
+                result = index_manager.load_index(example_indexes[index_name])
+                progress(1.0, desc="Index loaded!")
+                return result, None
             except Exception as e:
-                return f"Error loading index: {str(e)}"
-        return "No index selected"
+                return f"Error loading index: {str(e)}", None
+        return "No index selected", None
     
     existing_index_dropdown.change(
         fn=load_existing_index,
         inputs=[existing_index_dropdown],
-        outputs=[create_status],
-        api_name=False
+        outputs=[create_status, query_input],
+        api_name=False,
+        show_progress=True
     )
     
     create_btn.click(