Update app.py

app.py

@@ -1,14 +1,52 @@
 import streamlit as st
-from streamlit_option_menu import option_menu
 #for k, v in st.session_state.items():
 #    st.session_state[k] = v
 
-with st.sidebar:
-    selected=option_menu(
-    	menu_title = "SBS Mapper",
-    	options = ["Chapters for selection", "DEMO for text entry", "DEMO for file upload (coming)", "About the app"],
-    	icons = ["book", "keyboard", "upload", "info-circle"],
-        menu_icon = "receipt",
-        default_index = 0,
-    )
+   # --- SHARED ON ALL PAGES ---
+#st.logo(image=":material/medical_information:")
+#st.logo(image="images/medical_information_24dp_1F1F1F_FILL0_wght400_GRAD0_opsz24.png") 
+st.logo(image="images/menu_book_60dp_75FBFD.png")
+st.sidebar.title("SBS Codes V2.0 Mapper")
+
+# --- PAGE SETUP ---
+start_page = st.Page(
+    page="pages/chapter_index.py",
+    title="Chapters for selection",
+    icon=":material/home:",
+    default=True,)
+
+type_text_page = st.Page(
+    page="pages/type_text.py",
+    title="DEMO for text entry",
+    icon=":material/keyboard:",
+    default=False,)
+
+upload_file_page = st.Page(
+    page="pages/upload_file.py",
+    title="DEMO for file upload (work in progress)",
+    icon=":material/file_upload:",
+    default=False,)
+
+about_page = st.Page(
+    page="pages/about.py",
+    title="About the app",
+    icon=":material/info:",
+    default=False)
+
+#PAGES = {
+#    "Chapter Index": "pages/chapter_index.py" ,
+#    "DEMO type_text": "pages/type_text.py",
+#    "DEMO upload file (not yet active)": "pages/upload_file.py",
+#    "About": "pages/about.py",
+#}
+
+#selection = st.sidebar.radio("Pages", list(PAGES.keys()))
+#selection = st.sidebar.radio("Pages", [start_page, type_text_page, upload_file_page, about_page])
+#page = PAGES[selection]
+
+# --- NAVIGATION SETUP ---
+pg = st.navigation(pages=[start_page, type_text_page, upload_file_page, about_page]) # WITHOUT SECTIONS
+#pg = st.navigation({"Chapter_Index": [start_page], "Demo": [type_text_page, upload_file_page], "About": [about_page]}) # WITH SECTIONS
+pg.run() 
+
 st.sidebar.text("Project by JA-RAD")