hide the download button to avoid confusion before submit

app.py

@@ -36,7 +36,7 @@ def process(input_bib, shorten, remove_keys, deduplicate, sort):
         output_bib = f.read().replace("\n ", "\n    ")
     # delete both files
     # print(output_bib)
-    return output_bib, random_id
+    return output_bib, random_id, gr.update(visible=True)
 
 
 example_input = """
@@ -118,6 +118,7 @@ with gr.Blocks() as demo:
         with gr.Column(scale=3):
             output=gr.Textbox(label="Output BIB (Note that you can copy the output bib file by clicking the top-right button.)").style(show_copy_button=True, interactive=False)        
             download_btn = gr.Button("Generate Bib File")
+            download_btn.visible = False
             download_content = gr.outputs.File()
             download_content.visible = False 
     def download_file(ex_uuid):
@@ -127,7 +128,7 @@ with gr.Blocks() as demo:
         download_content.update(visible=False)
         return file_path, gr.update(visible=True)
     download_btn.click(download_file, inputs=ex_uuid, outputs=[download_content,download_content])  
-    button.click(process, inputs=[input_bib, shorten, removekeys, dedup, sort], outputs=[output, ex_uuid], api_name = "process")
+    button.click(process, inputs=[input_bib, shorten, removekeys, dedup, sort], outputs=[output, ex_uuid, download_btn], api_name = "process")
     def clean(text):
         return ""
     clr_button.click(clean, input_bib, input_bib)