You didn't miss anything. Transparency cannot be applied to graphics. The "Feature Layer" or "Image Editor" techniques is the only way. Would be a nice feature. Not even certain if there are any plans to do this in the future. Don't think production quality cartography is the ESRI's focus.
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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