Before sending the QAccessibleEvent QAccessible::ObjectShow event from QQuickItemPrivate::setEffectiveVisibleRecur() we checked if QQuickItemPrivate::isAccessible was set. For e.g. Button, isAccessible wasn't set by default: This was because isAccessible was only set as a response to that an Accessible attached property was assigned to the item. Therefore, when a Button was shown it could end up not sending the QAccessible::ObjectShow event. This problem was first found on Button, but after more investigation, we have found that the same problem applies to: * BusyIndicator * Button * ComboBox * Dial * Label (without a text) * ProgressBar * RangeSlider * RoundButton * Slider * TextArea * TextField The fix is to explicitly enable accessibility by calling QQuickItemPrivate::setAccessible() on *all* Qt Quick Controls, since they are all supposed to be accessible. Change-Id: If4fa050149a31bf2baffa208716341d21631c042 Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>