diff --git a/TODO.md b/TODO.md
index 6e47381..0c44b5a 100644
--- a/TODO.md
+++ b/TODO.md
@@ -468,11 +468,29 @@ TinyTUI 现在已经具备最小可运行的 C# TUI 框架骨架：终端输入
- 动态添加和动态移除都走同一套 Runtime 挂载计数，根树和 overlay 多路径挂载时仍能避免重复 mount 或提前 unmount
- C# 侧把“可枚举子树”和“可变子树事件”拆成两个接口，比参考实现依赖 `instanceof Container` 的递归判断更适合第三方组件扩展
+本次焦点生命周期修复推进：
+
+- `TuiRuntime.Remove` 和动态 `IMutableCompositeComponent.ChildRemoved` 路径会在卸载子树前递归检查当前焦点是否位于被移除子树内
+- 如果焦点命中被移除子树，Runtime 会优先切到当前最上层可聚焦 overlay；普通根树或动态容器移除则保守清空焦点
+- 子树检测复用 `ICompositeComponent.GetChildren()`，因此 `Container`、`Box` 和第三方复合组件都走同一套焦点清理逻辑
+- 新增 xUnit 回归测试，覆盖动态 `Container.Remove(focusedInput)`、`Container.Remove(boxContainingFocusedInput)` 和第三方 `IMutableCompositeComponent.Remove(subtree)` 后旧输入组件不再收到后续输入
+
+本次为什么这样做：
+
+- 对比 `tmp/tui/src/tui.ts`，参考实现通过 `containsComponent` / `isComponentMounted` 辅助判断焦点目标是否仍处于组件树内；C# 侧已有通用复合组件枚举契约，因此把判断落在 Runtime 子树移除边界即可避免 stale focus
+- 清理发生在 `UnmountRuntimeComponentTree` 前，是因为此时被移除子树仍可通过 `GetChildren()` 完整遍历，能可靠判断深层已聚焦子组件
+- 本轮不扩展完整 overlay blocked restore 机制，只在 overlay 场景使用现有 `_overlayManager.TopFocusableComponent` 作为安全 fallback，避免把焦点生命周期修复扩大成多层 overlay 重构
+
+本次当前更好的点：
+
+- C# 侧焦点清理支持第三方 `ICompositeComponent` / `IMutableCompositeComponent`，不依赖参考实现中的 `instanceof Container`
+- Runtime 统一在根移除和动态复合移除两条路径处理焦点，后续输入派发入口不需要每次再判断焦点组件是否仍挂载
+- 保守清空焦点能确保已卸载组件不会再接收输入，比继续保留显式 `SetFocus` 语义更安全
+
后续仍需补齐：
- Runtime 目前不会自动 `Dispose` 实现 `IDisposable` 的用户组件；后续需要明确所有权策略，比如仅 Dispose Runtime 自己创建的组件，或提供可选自动释放策略
- `IMutableCompositeComponent` 目前只表达直接子组件增删，没有批量变更、移动、替换或变更事务；如果后续出现高频动态列表，需要补批量事件或挂载 diff 策略减少重复注入
-- Runtime 对动态移除的已聚焦子组件暂未自动清焦点或重定向焦点；当前保持现有显式 `SetFocus` 语义，后续可结合 overlay 焦点恢复策略统一处理
- `SettingsList` 还没有移植，参考实现里的搜索、描述换行、值循环、submenu 委托和主题分区仍需单独推进
- `ITuiTheme` 当前仍是轻量样式接口，还没有 theme version、分区主题、Markdown 完整主题或控件级样式覆盖策略
- `Input` 目前仍是尾部输入模型，还没有参考实现里的水平滚动、按 grapheme 移动、kill ring 和 undo；这些应在输入/编辑能力后续增量中处理
diff --git a/src/TinyTUI/Runtime/TuiRuntime.cs b/src/TinyTUI/Runtime/TuiRuntime.cs
index f4f5a2e..7b243eb 100644
--- a/src/TinyTUI/Runtime/TuiRuntime.cs
+++ b/src/TinyTUI/Runtime/TuiRuntime.cs
@@ -104,14 +104,11 @@ public sealed class TuiRuntime : ITuiRuntime
if (!_root.Children.Contains(component))
return;
+ ClearFocusIfRemovedSubtreeContainsFocus(component);
UnmountRuntimeComponentTree(component);
_root.Remove(component);
- if (_focusedComponent == component)
- SetFocus(null);
- else
- component.Invalidate();
-
+ component.Invalidate();
RequestRender();
}
@@ -338,6 +335,42 @@ public sealed class TuiRuntime : ITuiRuntime
SetFocus(_overlayManager.TopFocusableComponent ?? restoreFocus);
}
+ ///
+ /// 移除组件子树前清理位于该子树内的焦点 避免输入继续派发到已卸载组件
+ ///
+ private void ClearFocusIfRemovedSubtreeContainsFocus(IComponent removedSubtree)
+ {
+ if (_focusedComponent is null || !ComponentTreeContains(removedSubtree, _focusedComponent))
+ return;
+
+ // overlay 场景优先交还给当前最上层可聚焦 overlay 其余普通动态移除保守清空焦点
+ var nextFocus = _overlayManager.TopFocusableComponent;
+ if (ReferenceEquals(nextFocus, _focusedComponent) || ComponentTreeContains(removedSubtree, nextFocus))
+ nextFocus = null;
+
+ SetFocus(nextFocus);
+ }
+
+ ///
+ /// 判断组件子树是否包含目标组件 递归复用复合组件公开的子组件枚举契约
+ ///
+ private static bool ComponentTreeContains(IComponent root, IComponent? target)
+ {
+ if (target is null)
+ return false;
+
+ if (ReferenceEquals(root, target))
+ return true;
+
+ foreach (var child in EnumerateRuntimeChildren(root))
+ {
+ if (ComponentTreeContains(child, target))
+ return true;
+ }
+
+ return false;
+ }
+
///
/// 统一写入组件焦点状态 组件自身只根据状态决定是否输出光标 marker
///
@@ -483,6 +516,8 @@ public sealed class TuiRuntime : ITuiRuntime
{
var parentMountCount = GetRuntimeMountCount(sender);
+ ClearFocusIfRemovedSubtreeContainsFocus(args.Component);
+
for (var index = 0; index < parentMountCount; index++)
UnmountRuntimeComponentTree(args.Component);
diff --git a/test/TinyTUI.Tests/Runtime/TuiRuntimeInputListenerTests.cs b/test/TinyTUI.Tests/Runtime/TuiRuntimeInputListenerTests.cs
index 08034a5..3a1d10b 100644
--- a/test/TinyTUI.Tests/Runtime/TuiRuntimeInputListenerTests.cs
+++ b/test/TinyTUI.Tests/Runtime/TuiRuntimeInputListenerTests.cs
@@ -320,6 +320,65 @@ public sealed class TuiRuntimeInputListenerTests
Assert.Same(keybindings, contextComponent.LastMountedContext?.Keybindings);
}
+ [Fact]
+ public void RemovingFocusedDynamicContainerChildClearsFocus()
+ {
+ var terminal = new TestTerminalSession();
+ using var runtime = new TuiRuntime(terminal, new DefaultInputParser(), new CountingRenderer());
+ var container = new Container();
+ var input = new RecordingInputComponent();
+
+ runtime.Add(container);
+ container.Add(input);
+ runtime.SetFocus(input);
+
+ runtime.Start();
+ container.Remove(input);
+ terminal.Receive("a");
+
+ Assert.Empty(input.Inputs);
+ }
+
+ [Fact]
+ public void RemovingBoxContainingFocusedChildClearsFocus()
+ {
+ var terminal = new TestTerminalSession();
+ using var runtime = new TuiRuntime(terminal, new DefaultInputParser(), new CountingRenderer());
+ var container = new Container();
+ var input = new RecordingInputComponent();
+ var box = new Box(input);
+
+ runtime.Add(container);
+ container.Add(box);
+ runtime.SetFocus(input);
+
+ runtime.Start();
+ container.Remove(box);
+ terminal.Receive("a");
+
+ Assert.Empty(input.Inputs);
+ }
+
+ [Fact]
+ public void RemovingThirdPartyMutableCompositeSubtreeContainingFocusedChildClearsFocus()
+ {
+ var terminal = new TestTerminalSession();
+ using var runtime = new TuiRuntime(terminal, new DefaultInputParser(), new CountingRenderer());
+ var composite = new ThirdPartyMutableComposite();
+ var input = new RecordingInputComponent();
+ var subtree = new ThirdPartyComposite(new Box(input));
+
+ runtime.Add(composite);
+ composite.Add(subtree);
+ runtime.SetFocus(input);
+
+ runtime.Start();
+ composite.Remove(subtree);
+ terminal.Receive("a");
+
+ Assert.Empty(input.Inputs);
+ }
+
[Fact]
public void RuntimeInjectedEditorKeybindingsReachAutocompleteList()
{