Do you have a basemap of your own that you want to use? As far as I know (which could be wrong) you need to have a least one basemap. I added in my own custom base map by going to the Settings (upper right hand corner when you open the viewer builder), under the tab basemap I added my own and you can remove the others if you want at that location.
サインインしたメンバーは投稿、更新のフォローなどができます。初めてですか?無料アカウントを登録してください。
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