update UI

app.py

@@ -16,10 +16,15 @@ st.title('Paper2Slides')
 
 st.subheader('Upload paper in pdf format')
 uploaded_file = st.file_uploader("Choose a file")
+
 if uploaded_file is not None:
     st.write(uploaded_file.name)
     bytes_data = uploaded_file.getvalue()
     st.write(len(bytes_data), "bytes")
+    option = st.selectbox(
+        'Please select one of the parsing method.',
+        ('monkey', 'x2d', 'lxml'))
+
     saved_file_path = save_uploaded_file(uploaded_file)
     
     client = GrobidClient(config_path="./grobidconfig.json")
@@ -29,7 +34,7 @@ if uploaded_file is not None:
                    tei_coordinates=True)
                    
     output_file_path = os.path.splitext(saved_file_path)[0] + ".grobid.tei.xml"
-    monkeyReader = reader.MonkeyReader('monkey')
+    monkeyReader = reader.MonkeyReader(option)
     outline = monkeyReader.readOutline(output_file_path)
     for pre, fill, node in outline:
         st.write("%s%s" % (pre, node.name))