Fixed updating of undo state on deleting item in photo editor.

Telegram/SourceFiles/editor/editor_paint.cpp

@@ -138,6 +138,12 @@ Paint::Paint(
 		clearRedoList();
 		updateUndoState();
 	}, lifetime());
+
+	_scene->removesItem(
+	) | rpl::start_with_next([=] {
+		updateUndoState();
+	}, lifetime());
+
 }
 
 void Paint::applyTransform(QRect geometry, int angle, bool flipped) {

Telegram/SourceFiles/editor/scene/scene.cpp

@@ -67,6 +67,7 @@ void Scene::removeItem(not_null<QGraphicsItem*> item) {
 
 void Scene::removeItem(const ItemPtr &item) {
 	_items.erase(ranges::remove(_items, item), end(_items));
+	_removesItem.fire({});
 }
 
 void Scene::mousePressEvent(QGraphicsSceneMouseEvent *event) {
@@ -101,6 +102,10 @@ rpl::producer<> Scene::addsItem() const {
 	return _addsItem.events();
 }
 
+rpl::producer<> Scene::removesItem() const {
+	return _removesItem.events();
+}
+
 std::vector<ItemPtr> Scene::items(
 		Qt::SortOrder order) const {
 	auto copyItems = _items;

Telegram/SourceFiles/editor/scene/scene.h

@@ -36,6 +36,7 @@ public:
 	void removeItem(not_null<QGraphicsItem*> item);
 	void removeItem(const ItemPtr &item);
 	[[nodiscard]] rpl::producer<> addsItem() const;
+	[[nodiscard]] rpl::producer<> removesItem() const;
 
 	[[nodiscard]] std::vector<MTPInputDocument> attachedStickers() const;
 
@@ -52,7 +53,7 @@ private:
 	float64 _lastLineZ = 0.;
 	int _itemNumber = 0;
 
-	rpl::event_stream<> _addsItem;
+	rpl::event_stream<> _addsItem, _removesItem;
 	rpl::lifetime _lifetime;
 
 };