Add compactSliderOnChange modifier to observe configuration

Author: buh

Sources/CompactSlider/CompactSlider.swift

@@ -133,6 +133,7 @@ public struct CompactSlider<Value: BinaryFloatingPoint, Point: CompactSliderPoin
     @Environment(\.compactSliderGridStyle) var compactSliderGridStyle
     @Environment(\.compactSliderCircularGridStyle) var compactSliderCircularGridStyle
     @Environment(\.compactSliderAnimations) var animations
+    @Environment(\.compactSliderOnChangeAction) var onChangeAction
 
     let bounds: ClosedRange<Value>
     let pointBounds: ClosedRange<Point>

Sources/CompactSlider/CompactSliderOnChangeAction.swift

@@ -0,0 +1,28 @@
+// The MIT License (MIT)
+//
+// Copyright (c) 2025 Alexey Bukhtin (github.com/buh).
+//
+
+import SwiftUI
+
+struct CompactSliderOnChangeActionKey: EnvironmentKey {
+    static var defaultValue: ((CompactSliderStyleConfiguration) -> Void)? = nil
+}
+
+extension EnvironmentValues {
+    var compactSliderOnChangeAction: ((CompactSliderStyleConfiguration) -> Void)? {
+        get { self[CompactSliderOnChangeActionKey.self] }
+        set { self[CompactSliderOnChangeActionKey.self] = newValue }
+    }
+}
+
+// MARK: - View
+
+extension View {
+    /// Adds an action to perform when the slider configuration (progress, focus state and etc) changes.
+    public func compactSliderOnChange(
+        action: @escaping (_ configuration: CompactSliderStyleConfiguration) -> Void
+    ) -> some View {
+        environment(\.compactSliderOnChangeAction, action)
+    }
+}