2019 Jun. 30.2019 Jun. 29.2019 Jun. 22.2019 May 31.2019 May 30.参照元 https://developer.android.com/guide/topics/ui/dialogs https://akira-watson.com/android/alertdialog.htmlhttp://furudate.hatenablog.com/entry/2014/01/09/162421[MainActivit…