onPreview
abstract fun onPreview(previewThumbnailView: PreviewThumbnailView, progress: Int, fromUser: Boolean)
Callback triggered when the Preview Thumbnail process is in progress
Parameters
previewThumbnailView
the PreviewThumbnailView triggering this action
progress
the PreviewThumbnailView's current progress
fromUser
indicates whether this action was triggered by the user or programmatically