private fun initRecyclerView() {
    // Create an adapter about change the operator status of the member
    // So It is possible to change the operator status of the member by clicking the item.
    adapter = ChatMemberListAdapter { member, position -> changeMemberOperatorStatus(member, position) }
    ...
}

// Change the operator status of the member
private fun changeMemberOperatorStatus(member: Member, position: Int) {
    // If the current user is the operator, the operator role cannot be changed.
    if (member.role == Role.OPERATOR) {
        // Call the removeOperators() method to remove the operator role from the member.
        removeOperatorRole(member, position)
        return
    }
    // If the current user is not the operator, the operator role can be changed.
    addOperatorRole(member, position)
}

// Add operator role to the member
private fun addOperatorRole(member: Member, position: Int) {
    // Call the addOperators() method to add the operator role to the member.
    currentChannel?.addOperators(listOf(member.userId)) { exception ->
        if (exception != null) {
            showToast("${exception.message}")
            return@addOperators
        }
        showToast("User made operator")
        // Refresh the member if the member is not Operator refresh one more time.
        refreshMember(member, position, true)
    }
}

// Remove operator role from the member
private fun removeOperatorRole(member: Member, position: Int) {
    // Call the removeOperators() method to remove the operator role from the member.
    currentChannel?.removeOperators(listOf(member.userId)) { exception ->
        if (exception != null) {
            showToast("${exception.message}")
            return@removeOperators
        }
        showToast("User back to basic")
        // Refresh the member
        refreshMember(member, position,false)
    }
}

// Refresh the member
private fun refreshMember(member: Member, position: Int, isOperator: Boolean) {
    currentChannel?.createMemberListQuery(MemberListQueryParams())?.next { list, e ->
        if (e != null) {
            showToast("${e.message}")
            return@next
        }
        if (list != null) {
            // check if the member is Operator in the list about same userId from member.
            val operator = list.find { it.userId == member.userId }?.role == Role.OPERATOR
            // and Check operator is same with isOperator
            if (operator == isOperator) {
                // If the member is Operator and isOperator is true or
                // If the member is not Operator and isOperator is false
                // Refresh the member
                adapter.notifyItemChanged(position)
                return@next
            }else{
                // refresh one more time
                refreshMember(member, position, isOperator)
            }
        }
    }
}