Update app.py

app.py

@@ -89,9 +89,6 @@ def update_dropdown_options(cytof_img, selected_self, selected_other1, selected_
     Remove the selected option in the dropdown from the other two dropdowns
     """
     updated_choices = cytof_img.channels.copy()
-    selected_self = selected_self or []
-    selected_other1 = selected_other1 or []
-    selected_other2 = selected_other2 or []
     unavail_options = selected_self + selected_other1 + selected_other2
     for opt in unavail_options:
         updated_choices.remove(opt)
@@ -440,9 +437,9 @@ with gr.Blocks() as demo:
     
     with gr.Row(equal_height=True): # third row selects nuclei channels
         with gr.Column(scale=2):
-            selected_nuclei = gr.Dropdown(label='(Required) Select the nuclei channel', interactive=True)
-            selected_unwanted_channel = gr.Dropdown(label='(Optional) Select the unwanted channel', interactive=True)
-            selected_membrane = gr.Dropdown(label='(Optional) Select the membrane channel', interactive=True)
+            selected_nuclei = gr.Dropdown(label='(Required) Select the nuclei channel', interactive=True, multiselect=True)
+            selected_unwanted_channel = gr.Dropdown(label='(Optional) Select the unwanted channel', interactive=True, multiselect=True)
+            selected_membrane = gr.Dropdown(label='(Optional) Select the membrane channel', interactive=True, multiselect=True)
             define_btn = gr.Button('Modify channels')
         with gr.Column(scale=3):
             channel_feedback = gr.Textbox(label='Channels info update')