Update app.py

app.py

@@ -66,14 +66,14 @@ with gr.Blocks(css=css) as demo:
         
         with gr.Column():
             pdf_doc = gr.File(label="Load a pdf", file_types=['.pdf'], type="file")
-            with gr.Row():
-                langchain_status = gr.Textbox(label="Status", placeholder="", interactive=False)
-                load_pdf = gr.Button("Load pdf to langchain")
-        
+            langchain_status = gr.Textbox(label="Status", placeholder="", interactive=False)
+            load_pdf = gr.Button("Load PDF")
+            Book = gr.Dropdown(label="Books", choices=["Book 1", "Book 2", "Book 3"], value=["Book 1", "Book 2", "Book 3"])
         chatbot = gr.Chatbot([], elem_id="chatbot").style(height=350)
         question = gr.Textbox(label="Question", placeholder="Type your question and hit Enter ")
         submit_btn = gr.Button("Send message")
     #load_pdf.click(loading_pdf, None, langchain_status, queue=False)    
+    Book.change(pdf_changes, inputs=[Book], outputs=[langchain_status], queue=False)
     load_pdf.click(pdf_changes, inputs=[pdf_doc], outputs=[langchain_status], queue=False)
     question.submit(add_text, [chatbot, question], [chatbot, question]).then(
         bot, chatbot, chatbot