From 0099bf4aa548f272985ed22c6eff30f46b753193 Mon Sep 17 00:00:00 2001
From: andy840119 <andy840119@gmail.com>
Date: Sun, 19 May 2024 23:19:10 +0800
Subject: [PATCH] Use quick way to fix this issue. DI object might be null in
 the dispose method.

see:
- https://github.com/ppy/osu/commit/b11ae1c5714b43d33ebbec569faf6569d0304c25
---
 .../Screens/Edit/Beatmaps/Lyrics/LyricEditorVerifier.cs      | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/osu.Game.Rulesets.Karaoke/Screens/Edit/Beatmaps/Lyrics/LyricEditorVerifier.cs b/osu.Game.Rulesets.Karaoke/Screens/Edit/Beatmaps/Lyrics/LyricEditorVerifier.cs
index 5c119bd68..7b1c81c6b 100644
--- a/osu.Game.Rulesets.Karaoke/Screens/Edit/Beatmaps/Lyrics/LyricEditorVerifier.cs
+++ b/osu.Game.Rulesets.Karaoke/Screens/Edit/Beatmaps/Lyrics/LyricEditorVerifier.cs
@@ -7,6 +7,7 @@
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Caching;
+using osu.Framework.Extensions.ObjectExtensions;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Edit;
 using osu.Game.Rulesets.Edit.Checks.Components;
@@ -182,6 +183,10 @@ protected override void Dispose(bool isDisposing)
     {
         base.Dispose(isDisposing);
 
+        // todo: not very sure
+        if (!editorBeatmap.IsNull())
+            return;
+
         editorBeatmap.HitObjectAdded -= hitObjectAdded;
         editorBeatmap.HitObjectRemoved -= hitObjectRemoved;
         editorBeatmap.HitObjectUpdated -= hitObjectUpdated;