新增 FlowScope Git 包雏形

Packages/com.flowscope.gamecore/Runtime/UI/UIScreenNavigator.cs

@@ -0,0 +1,50 @@
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace FlowScope.UI
+{
+    public sealed class UIScreenNavigator : IUIScreenNavigator
+    {
+        private readonly UIManager _uiManager;
+        private readonly Stack<Action> _closeStack = new();
+
+        public UIScreenNavigator(UIManager uiManager)
+        {
+            _uiManager = uiManager ?? throw new ArgumentNullException(nameof(uiManager));
+        }
+
+        public bool CanGoBack => _closeStack.Count > 1;
+
+        public async Task<TPanel> PushAsync<TPanel, TViewModel>(
+            TViewModel viewModel,
+            CancellationToken cancellationToken)
+            where TPanel : UIPanelBase<TViewModel>
+        {
+            var panel = await _uiManager.OpenAsync<TPanel, TViewModel>(viewModel, cancellationToken);
+            _closeStack.Push(() => _uiManager.Close<TPanel>());
+            return panel;
+        }
+
+        public void GoBack()
+        {
+            if (!CanGoBack)
+            {
+                return;
+            }
+
+            var close = _closeStack.Pop();
+            close();
+        }
+
+        public void Clear()
+        {
+            while (_closeStack.Count > 0)
+            {
+                var close = _closeStack.Pop();
+                close();
+            }
+        }
+    }
+}