[Flutter]photo_viewパッケージを使っているプロジェクトで「Looking up a deactivated widget’s ancestor is unsafe」というエラーが出た場合の対処法（動画なし）

Flutterで画像をピンチイン・アウトで拡大・縮小できる大変便利な「photo_view」という有名なパッケージがありますが、

photo_view | Flutter package

Photo View provides a gesture sensitive zoomable widget. Photo View is largely used to show interactive images and other stuff such as SVG.

このパッケージを使っているプロジェクトで画面遷移等を行った際に、

The following assertion was thrown while finalizing the widget tree:
Looking up a deactivated widget's ancestor is unsafe.

At this point the state of the widget's element tree is no longer stable.

To safely refer to a widget's ancestor in its dispose() method, save a reference to the ancestor by calling dependOnInheritedWidgetOfExactType() in the widget's didChangeDependencies() method.

というエラーが出てしまう場合があります（アプリは落ちないが）。

これは、photo_viewパッケージのissueにも上がっていているのですが、現時点（2022/4）ではまだ解決されていないようなので、以下の次善の策を施してやる必要があるようです。

（pubspec.yamlファイルの「dependency_override」欄に以下を追記）

dependency_overrides:
  photo_view:
    git:
      url: https://github.com/bluefireteam/photo_view
      ref: master

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