Add control for arbitrary-numerator time signatures

osu.Game/Screens/Edit/Timing/LabelledTimeSignature.cs

@@ -0,0 +1,93 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.UserInterface;
+using osu.Game.Beatmaps.Timing;
+using osu.Game.Graphics;
+using osu.Game.Graphics.Sprites;
+using osu.Game.Graphics.UserInterface;
+using osu.Game.Graphics.UserInterfaceV2;
+
+namespace osu.Game.Screens.Edit.Timing
+{
+    internal class LabelledTimeSignature : LabelledComponent<LabelledTimeSignature.TimeSignatureBox, TimeSignature>
+    {
+        public LabelledTimeSignature()
+            : base(false)
+        {
+        }
+
+        protected override TimeSignatureBox CreateComponent() => new TimeSignatureBox();
+
+        internal class TimeSignatureBox : CompositeDrawable, IHasCurrentValue<TimeSignature>
+        {
+            private readonly BindableWithCurrent<TimeSignature> current = new BindableWithCurrent<TimeSignature>(TimeSignature.SimpleQuadruple);
+
+            public Bindable<TimeSignature> Current
+            {
+                get => current.Current;
+                set => current.Current = value;
+            }
+
+            private OsuNumberBox numeratorBox;
+
+            [BackgroundDependencyLoader]
+            private void load()
+            {
+                AutoSizeAxes = Axes.Both;
+                InternalChild = new FillFlowContainer
+                {
+                    AutoSizeAxes = Axes.Both,
+                    Direction = FillDirection.Horizontal,
+                    Children = new Drawable[]
+                    {
+                        numeratorBox = new OsuNumberBox
+                        {
+                            Width = 40,
+                            Anchor = Anchor.CentreLeft,
+                            Origin = Anchor.CentreLeft,
+                            CornerRadius = CORNER_RADIUS,
+                            CommitOnFocusLost = true
+                        },
+                        new OsuSpriteText
+                        {
+                            Anchor = Anchor.CentreLeft,
+                            Origin = Anchor.CentreLeft,
+                            Margin = new MarginPadding(10),
+                            Text = "/4",
+                            Font = OsuFont.Default.With(size: 20)
+                        }
+                    }
+                };
+            }
+
+            protected override void LoadComplete()
+            {
+                base.LoadComplete();
+
+                Current.BindValueChanged(_ => updateFromCurrent(), true);
+                numeratorBox.OnCommit += (_, __) => updateFromNumeratorBox();
+            }
+
+            private void updateFromCurrent()
+            {
+                numeratorBox.Current.Value = Current.Value.Numerator.ToString();
+            }
+
+            private void updateFromNumeratorBox()
+            {
+                if (int.TryParse(numeratorBox.Current.Value, out int numerator) && numerator > 0)
+                    Current.Value = new TimeSignature(numerator);
+                else
+                {
+                    // trigger `Current` change to restore the numerator box's text to a valid value.
+                    Current.TriggerChange();
+                }
+            }
+        }
+    }
+}