Add method for able to change time-tag romaji text and the initial state in the change handler.

osu.Game.Rulesets.Karaoke.Tests/Editor/ChangeHandlers/Lyrics/LyricTimeTagsChangeHandlerTest.cs

@@ -84,6 +84,55 @@ public void TestSetTimeTagTime()
         });
     }
 
+    [Test]
+    public void TestSetTimeTagInitialRomaji()
+    {
+        var timeTag = new TimeTag(new TextIndex(), 1000);
+        PrepareHitObject(() => new Lyric
+        {
+            Text = "カラオケ",
+            TimeTags = new[]
+            {
+                timeTag,
+            },
+        });
+
+        TriggerHandlerChanged(c => c.SetTimeTagInitialRomaji(timeTag, true));
+
+        AssertSelectedHitObject(_ =>
+        {
+            Assert.AreEqual(true, timeTag.InitialRomaji);
+        });
+    }
+
+    [Test]
+    public void TestSetTimeTagRomajiText()
+    {
+        var timeTag = new TimeTag(new TextIndex(), 1000);
+        PrepareHitObject(() => new Lyric
+        {
+            Text = "カラオケ",
+            TimeTags = new[]
+            {
+                timeTag,
+            },
+        });
+
+        TriggerHandlerChanged(c => c.SetTimeTagRomajiText(timeTag, "karaoke"));
+
+        AssertSelectedHitObject(_ =>
+        {
+            Assert.AreEqual("karaoke", timeTag.RomajiText);
+        });
+
+        TriggerHandlerChanged(c => c.SetTimeTagRomajiText(timeTag, "  "));
+
+        AssertSelectedHitObject(_ =>
+        {
+            Assert.AreEqual(string.Empty, timeTag.RomajiText);
+        });
+    }
+
     [Test]
     public void TestShiftingTimeTagTime()
     {

osu.Game.Rulesets.Karaoke/Edit/ChangeHandlers/Lyrics/ILyricTimeTagsChangeHandler.cs

@@ -11,6 +11,10 @@ public interface ILyricTimeTagsChangeHandler : ILyricListPropertyChangeHandler<T
 {
     void SetTimeTagTime(TimeTag timeTag, double time);
 
+    void SetTimeTagInitialRomaji(TimeTag timeTag, bool initialRomaji);
+
+    void SetTimeTagRomajiText(TimeTag timeTag, string romaji);
+
     void ShiftingTimeTagTime(IEnumerable<TimeTag> timeTags, double offset);
 
     void ClearTimeTagTime(TimeTag timeTag);

osu.Game.Rulesets.Karaoke/Edit/ChangeHandlers/Lyrics/LyricTimeTagsChangeHandler.cs

@@ -55,6 +55,40 @@ public void SetTimeTagTime(TimeTag timeTag, double time)
         });
     }
 
+    public void SetTimeTagInitialRomaji(TimeTag timeTag, bool initialRomaji)
+    {
+        CheckExactlySelectedOneHitObject();
+
+        PerformOnSelection(lyric =>
+        {
+            bool containsInLyric = lyric.TimeTags.Contains(timeTag);
+            if (!containsInLyric)
+                throw new InvalidOperationException($"{nameof(timeTag)} is not in the lyric");
+
+            timeTag.InitialRomaji = initialRomaji;
+        });
+    }
+
+    public void SetTimeTagRomajiText(TimeTag timeTag, string romaji)
+    {
+        CheckExactlySelectedOneHitObject();
+
+        PerformOnSelection(lyric =>
+        {
+            bool containsInLyric = lyric.TimeTags.Contains(timeTag);
+            if (!containsInLyric)
+                throw new InvalidOperationException($"{nameof(timeTag)} is not in the lyric");
+
+            timeTag.RomajiText = romaji;
+
+            if (!string.IsNullOrWhiteSpace(romaji))
+                return;
+
+            timeTag.RomajiText = string.Empty;
+            timeTag.InitialRomaji = false;
+        });
+    }
+
     public void ShiftingTimeTagTime(IEnumerable<TimeTag> timeTags, double offset)
     {
         CheckExactlySelectedOneHitObject();