Update app.py

app.py

@@ -63,8 +63,14 @@ def inference(audio_file: str, model_name: str, vocals: bool, drums: bool, bass:
             stems[stem] = stem_path
             yield None, stream_log(f"Found {stem} stem")
 
-    selected_stems: List[str] = [stems[stem] for stem in stems if locals()[stem]]
+    selected_stems: List[str] = []
+    for stem, selected in zip(["vocals", "drums", "bass", "other"], [vocals, drums, bass, other]):
+        if selected and stem in stems:
+            selected_stems.append(stems[stem])
+            yield None, stream_log(f"Selected {stem} stem for mixing")
+
     if not selected_stems:
+        yield None, stream_log("Error: No stems selected for mixing")
         raise gr.Error("Please select at least one stem to mix.")
 
     output_file: str = os.path.join(output_dir, "mixed.wav")