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+# Issues 9–20 (#34–#45): Dependency Analysis & Two-Person Split
+
+Scope: the twelve "Structure migrations" sub-issues of #26 (Eliminating
+EventBridge), GitHub issues #34–#45. Each is independently shippable; this
+document captures the real ordering constraints so two people can work in
+parallel without stepping on each other.
+
+## Hard dependencies
+
+Only two kinds exist:
+
+1. **The issue 7 signal (`Core::undo_index_changed`)** — required by issues
+   9, 11, 15, 16 (and used by 10/12/13/17 for undo refresh).
+   ✅ Already landed in `a030f2da2` (issue 7 / #55). **No longer blocks
+   anything.**
+
+2. **The issue 15 "project load finished" hook** (`Core` broadcasts after
+   TaskDialog load success). Explicitly reused by:
+   - **issue 13 (#38)** — "re-read uniformly after undo/**load**"
+   - **issue 17 (#42)** — "undo and **load** rebuild uniformly"
+   - **issue 19 (#44)** — "on load completion do a uniform model reset
+     (**reuse the issue 15 hook**)"
+
+Everything else has **no ordering constraints**.
+
+## Dependency graph
+
+```
+issue 7 (done) ──┬─> 9, 10, 11, 12, 16        (undo refresh signal, available now)
+                 └─> 15 ──┬─> 13              (project-load hook)
+                          ├─> 17
+                          └─> 19
+14, 18, 20 — fully independent
+```
+
+## File-overlap (merge-conflict) risks
+
+| Pair | Overlap | Severity |
+|------|---------|----------|
+| 15 / 16 | both in `app/widget/nodeview/` (+ `mainwindow.cpp` in 16) | low — different files |
+| 17 / 18 | both in `app/widget/timelinewidget/` (17 heavily edits `timelinewidget.cpp`) | medium — keep in the same person's queue |
+| 12 / 13 / 14 | all under `app/widget/nodeparamview/` | low — different files |
+| 9 / 10 | marker/workarea pattern is identical; not the same files | none, but cheap to do together |
+
+## Suggested split
+
+**Person A — "signals already available" batch (start immediately):**
+
+- issue 9 (#34) — seekablewidget marker/workarea
+- issue 10 (#35) — resizabletimelinescrollbar marker/workarea (same pattern as 9)
+- issue 11 (#36) — nodeviewitem label/color/message/array
+- issue 12 (#37) — NodeParamViewItem / arraywidget / keyframecontrol
+- issue 14 (#39) — NodeParamView group passthrough / context
+- issue 20 (#45) — misc leftovers
+
+**Person B — "project-load hook" chain (15 first, then its dependents):**
+
+- issue 15 (#40) — nodeviewcontext structure core + **add the load hook**
+- issue 16 (#41) — nodeview NODE_REMOVED_FROM_GRAPH (same area as 15)
+- issue 13 (#38) — nodeparamviewwidgetbridge values (needs the hook)
+- issue 17 (#42) — timelinewidget track/block structure (needs the hook; keeps 18's neighbor in one queue)
+- issue 18 (#43) — trackviewitem index/muted
+- issue 19 (#44) — projectviewmodel folder/label (needs the hook)
+
+Rationale: B owns everything that consumes the issue 15 hook, so the hook's
+API is designed and used by one person with no cross-team blocking. A's
+batch only needs the already-landed issue 7 signal, so both can start today.
+Workload is ~6 × 0.5 day each side.
+
+Ground rules still apply per issue: `cmake --build cmake-build-debug -j8 &&
+cd cmake-build-debug && ctest -j4` must be green (122/122) before shipping,
+and remove the matching `bridge_->subscribe` / `oakengine_event_subscribe`
+calls when done.
diff --git a/docs/zh/plans/issues-9-20-dependency-plan.md b/docs/zh/plans/issues-9-20-dependency-plan.md
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+# Issues 9–20（#34–#45）：依赖关系梳理与两人分工建议
+
+范围：#26（Eliminating EventBridge）的 12 个 "Structure migrations"
+子任务，对应 GitHub issue #34–#45。每个 issue 都可以独立交付，本文档
+梳理真实的先后约束，让两个人可以并行推进而互不阻塞。
+
+## 硬依赖
+
+只有两类：
+
+1. **issue 7 的信号（`Core::undo_index_changed`）** —— issue 9、11、
+   15、16 明确依赖它（10/12/13/17 的 undo 刷新也要用）。
+   ✅ 已在 `a030f2da2` 落地（issue 7 / #55）。**不再构成阻塞。**
+
+2. **issue 15 新增的 "project load finished" 钩子**（Core 在 TaskDialog
+   加载成功后广播）。明确复用它的有：
+   - **issue 13（#38）** —— "re-read uniformly after undo/**load**"
+   - **issue 17（#42）** —— "undo and **load** rebuild uniformly"
+   - **issue 19（#44）** —— "on load completion do a uniform model
+     reset（**复用 issue 15 的钩子**）"
+
+其余 issue **没有任何先后约束**。
+
+## 依赖图
+
+```
+issue 7（已完成） ──┬─> 9, 10, 11, 12, 16   （undo 刷新信号，现已可用）
+                   └─> 15 ──┬─> 13          （项目加载钩子）
+                            ├─> 17
+                            └─> 19
+14、18、20 —— 完全独立
+```
+
+## 文件重叠（合并冲突）风险
+
+| 组合 | 重叠区域 | 程度 |
+|------|---------|------|
+| 15 / 16 | 都在 `app/widget/nodeview/`（16 还涉及 `mainwindow.cpp`） | 低——不同文件 |
+| 17 / 18 | 都在 `app/widget/timelinewidget/`（17 会大改 `timelinewidget.cpp`） | 中——建议排在同一个人的队列里 |
+| 12 / 13 / 14 | 都在 `app/widget/nodeparamview/` 下 | 低——不同文件 |
+| 9 / 10 | marker/workarea 的处理模式完全相同，但不是同一批文件 | 无冲突，但连着做成本低 |
+
+## 建议分工
+
+**A 同学 —— "信号已就绪" 批次（今天就能开始）：**
+
+- issue 9（#34）—— seekablewidget marker/workarea
+- issue 10（#35）—— resizabletimelinescrollbar marker/workarea（与 9 同模式）
+- issue 11（#36）—— nodeviewitem label/color/message/array
+- issue 12（#37）—— NodeParamViewItem / arraywidget / keyframecontrol
+- issue 14（#39）—— NodeParamView group passthrough / context
+- issue 20（#45）—— 零散收尾
+
+**B 同学 —— "项目加载钩子" 链（先做 15，再做它的下游）：**
+
+- issue 15（#40）—— nodeviewcontext 结构核心 + **新增加载钩子**
+- issue 16（#41）—— nodeview NODE_REMOVED_FROM_GRAPH（与 15 同区域）
+- issue 13（#38）—— nodeparamviewwidgetbridge 参数值（依赖钩子）
+- issue 17（#42）—— timelinewidget track/block 结构（依赖钩子；同时把 18 的邻域保持在同一队列）
+- issue 18（#43）—— trackviewitem index/muted
+- issue 19（#44）—— projectviewmodel folder/label（依赖钩子）
+
+理由：所有消费 issue 15 钩子的 issue 都归 B，钩子的 API 由同一个人
+设计并使用，零跨人阻塞；A 的批次只依赖已经落地的 issue 7 信号，
+两人今天都能开工。工作量两侧均约为 6 × 0.5 天。
+
+每个 issue 的通用要求不变：提交前
+`cmake --build cmake-build-debug -j8 && cd cmake-build-debug && ctest -j4`
+必须全绿（122/122），完成后移除对应的
+`bridge_->subscribe` / `oakengine_event_subscribe` 调用。