Naturally, Indicator of ScrollView is visible when the content view of ScrollView is longer than ScrollView height and user drag on Screen. As we all know It is a default functionality, we can't make it always visible directly.

Using flashScrollIndicators() method we can make it visible.

Example

override func viewDidAppear(_ animated: Bool) {
 super.viewDidAppear(true)
 scrollView.flashScrollIndicators()
 }

But indicator only appears for some time after...

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