diff --git a/src/app/index.tsx b/src/app/index.tsx
index 6297ed8..b99165e 100644
--- a/src/app/index.tsx
+++ b/src/app/index.tsx
@@ -5,12 +5,11 @@ import { useSafeAreaInsets } from "react-native-safe-area-context";
 import { CoverGrid } from "@/components/cover/CoverGrid";
 import { CreatePanel } from "@/components/cover/CreatePanel";
 import { PromptModal } from "@/components/ui/PromptModal";
-import { pickBackup } from "@/lib/backup";
 import { notebookDisplayName } from "@/lib/model";
 import { colors, fonts } from "@/lib/theme";
 import type { NotebookType } from "@/lib/types";
+import { useImportBackup } from "@/state/backup";
 import { useNotebooks } from "@/state/notebooks";
-import { useUi } from "@/state/ui";
 
 export default function CoverScreen() {
   const router = useRouter();
@@ -22,8 +21,6 @@ export default function CoverScreen() {
   const deleteNotebook = useNotebooks((s) => s.deleteNotebook);
   const renameNotebook = useNotebooks((s) => s.renameNotebook);
   const recheckStorage = useNotebooks((s) => s.recheckStorage);
-  const importState = useNotebooks((s) => s.importState);
-  const showToast = useUi((s) => s.showToast);
 
   const [creating, setCreating] = useState(false);
   const [renameId, setRenameId] = useState<string | null>(null);
@@ -43,29 +40,7 @@ export default function CoverScreen() {
     ]);
   };
 
-  const onImport = async () => {
-    const res = await pickBackup();
-    if (res.status === "canceled") return;
-    if (res.status === "invalid") {
-      showToast("⚠️ 読み込みに失敗しました…ファイルを確認してね");
-      return;
-    }
-    Alert.alert(
-      "バックアップを読み込む",
-      "現在のすべての手帳を、このバックアップの内容で上書きします。よろしいですか？",
-      [
-        { text: "やめる", style: "cancel" },
-        {
-          text: "上書き",
-          style: "destructive",
-          onPress: () => {
-            importState(res.state);
-            showToast("バックアップを読み込みました🌸");
-          },
-        },
-      ],
-    );
-  };
+  const onImport = useImportBackup();
 
   const renameTarget = notebooks.find((n) => n.id === renameId);
 
diff --git a/src/app/notebook/[id].tsx b/src/app/notebook/[id].tsx
index 54a879c..4dce7a2 100644
--- a/src/app/notebook/[id].tsx
+++ b/src/app/notebook/[id].tsx
@@ -12,11 +12,12 @@ import { StickerTray } from "@/components/board/StickerTray";
 import { FlowchartSection } from "@/components/flowchart/FlowchartSection";
 import { FreeformCanvas } from "@/components/freeform/FreeformCanvas";
 import { NotebookSection } from "@/components/notebook/NotebookSection";
-import { exportBackup, pickBackup } from "@/lib/backup";
+import { exportBackup } from "@/lib/backup";
 import { captureAndShare } from "@/lib/capture";
 import { pickPhotoAsDataUrl } from "@/lib/files";
 import { colors, fonts, TRAY_BASE_HEIGHT } from "@/lib/theme";
 import type { StickerType } from "@/lib/types";
+import { useImportBackup } from "@/state/backup";
 import { selectCurrentNotebook, selectCurrentPage, useNotebooks } from "@/state/notebooks";
 import { useUi } from "@/state/ui";
 
@@ -46,7 +47,6 @@ export default function NotebookEditor() {
   const addShape = useNotebooks((s) => s.addShape);
   const addPhotoTo = useNotebooks((s) => s.addPhotoTo);
   const undo = useNotebooks((s) => s.undo);
-  const importState = useNotebooks((s) => s.importState);
 
   const connectMode = useUi((s) => s.connectMode);
   const select = useUi((s) => s.select);
@@ -65,6 +65,8 @@ export default function NotebookEditor() {
     useUi.getState().resetBoardUi();
   }, [page?.id]);
 
+  const onImport = useImportBackup(() => router.replace("/"));
+
   const goBack = () => {
     if (router.canGoBack()) router.back();
     else router.replace("/");
@@ -136,30 +138,6 @@ export default function NotebookEditor() {
       showToast("書き出しに失敗しました…");
     }
   };
-  const onImport = async () => {
-    const res = await pickBackup();
-    if (res.status === "canceled") return;
-    if (res.status === "invalid") {
-      showToast("⚠️ 読み込みに失敗しました…ファイルを確認してね");
-      return;
-    }
-    Alert.alert(
-      "バックアップを読み込む",
-      "現在のすべての手帳を、このバックアップの内容で上書きします。よろしいですか？",
-      [
-        { text: "やめる", style: "cancel" },
-        {
-          text: "上書き",
-          style: "destructive",
-          onPress: () => {
-            importState(res.state);
-            showToast("バックアップを読み込みました🌸");
-            router.replace("/");
-          },
-        },
-      ],
-    );
-  };
   const onReset = () => {
     Alert.alert("ページを消去", "このページの中身を全部消します。よろしいですか？", [
       { text: "やめる", style: "cancel" },
diff --git a/src/lib/model.ts b/src/lib/model.ts
index c1be45b..1f4fce9 100644
--- a/src/lib/model.ts
+++ b/src/lib/model.ts
@@ -10,6 +10,7 @@ import type {
   Page,
   PageType,
   Photo,
+  Placement,
   RuleStyle,
   Shape,
   Step,
@@ -215,14 +216,21 @@ function normalizeStep(raw: unknown): Step {
   return { id: str(r.id) || newId(), type: "step", text: str(r.text), done: bool(r.done) };
 }
 
-function normalizeSticker(raw: unknown): Sticker {
-  const r = rec(raw);
+// ステッカー・シェイプ・写真に共通する配置情報（id と座標・回転）を正規化する。
+function normalizePlacement(r: Record<string, unknown>): Placement {
   return {
     id: str(r.id) || newId(),
-    type: oneOf<StickerType>(r.type, STICKER_TYPES, "star"),
     x: clampNum(r.x, 0, 0, MAX_POSITION),
     y: clampNum(r.y, 0, 0, MAX_POSITION),
     rot: num(r.rot),
+  };
+}
+
+function normalizeSticker(raw: unknown): Sticker {
+  const r = rec(raw);
+  return {
+    ...normalizePlacement(r),
+    type: oneOf<StickerType>(r.type, STICKER_TYPES, "star"),
     size: clampNum(r.size, STICKER_DEFAULT_SIZE, STICKER_MIN_SIZE, STICKER_MAX_SIZE),
   };
 }
@@ -230,12 +238,9 @@ function normalizeSticker(raw: unknown): Sticker {
 function normalizeShape(raw: unknown): Shape {
   const r = rec(raw);
   return {
-    id: str(r.id) || newId(),
+    ...normalizePlacement(r),
     text: str(r.text),
-    x: clampNum(r.x, 0, 0, MAX_POSITION),
-    y: clampNum(r.y, 0, 0, MAX_POSITION),
     w: clampNum(r.w, SHAPE_DEFAULT_WIDTH, SHAPE_MIN_WIDTH, SHAPE_MAX_WIDTH),
-    rot: num(r.rot),
   };
 }
 
@@ -244,11 +249,8 @@ function normalizePhoto(raw: unknown): Photo | null {
   const dataUrl = str(r.dataUrl) || str(r.image);
   if (!/^data:image\//i.test(dataUrl)) return null;
   return {
-    id: str(r.id) || newId(),
-    x: clampNum(r.x, 0, 0, MAX_POSITION),
-    y: clampNum(r.y, 0, 0, MAX_POSITION),
+    ...normalizePlacement(r),
     w: clampNum(r.w, PHOTO_DEFAULT_WIDTH, PHOTO_MIN_WIDTH, PHOTO_MAX_WIDTH),
-    rot: num(r.rot),
     dataUrl,
   };
 }
diff --git a/src/lib/types.ts b/src/lib/types.ts
index 629d58e..cb30d70 100644
--- a/src/lib/types.ts
+++ b/src/lib/types.ts
@@ -31,30 +31,26 @@ export type Step = NormalStep | IfStep;
 
 export type BranchKey = "yes" | "no";
 
-export interface Sticker {
+// ボード上に配置される装飾（ステッカー・テキスト・写真）に共通する配置情報。
+export interface Placement {
   id: string;
-  type: StickerType;
   x: number;
   y: number;
   rot: number;
+}
+
+export interface Sticker extends Placement {
+  type: StickerType;
   size: number;
 }
 
-export interface Shape {
-  id: string;
+export interface Shape extends Placement {
   text: string;
-  x: number;
-  y: number;
   w: number;
-  rot: number;
 }
 
-export interface Photo {
-  id: string;
-  x: number;
-  y: number;
+export interface Photo extends Placement {
   w: number;
-  rot: number;
   dataUrl: string;
 }
 
diff --git a/src/state/backup.ts b/src/state/backup.ts
new file mode 100644
index 0000000..61232af
--- /dev/null
+++ b/src/state/backup.ts
@@ -0,0 +1,37 @@
+import { Alert } from "react-native";
+import { pickBackup } from "@/lib/backup";
+import { useNotebooks } from "@/state/notebooks";
+import { useUi } from "@/state/ui";
+
+// バックアップファイルを選ばせ、確認ダイアログを経て文書全体を上書き取り込みする共通フック。
+// 一覧画面・編集画面のどちらからも使う。取り込み完了後に onImported があれば呼ぶ
+// （編集画面では一覧へ戻るために使う）。
+export function useImportBackup(onImported?: () => void): () => Promise<void> {
+  const importState = useNotebooks((s) => s.importState);
+  const showToast = useUi((s) => s.showToast);
+
+  return async () => {
+    const res = await pickBackup();
+    if (res.status === "canceled") return;
+    if (res.status === "invalid") {
+      showToast("⚠️ 読み込みに失敗しました…ファイルを確認してね");
+      return;
+    }
+    Alert.alert(
+      "バックアップを読み込む",
+      "現在のすべての手帳を、このバックアップの内容で上書きします。よろしいですか？",
+      [
+        { text: "やめる", style: "cancel" },
+        {
+          text: "上書き",
+          style: "destructive",
+          onPress: () => {
+            importState(res.state);
+            showToast("バックアップを読み込みました🌸");
+            onImported?.();
+          },
+        },
+      ],
+    );
+  };
+}