ViewStateProtocol extension

ViewStateProtocolExtension_AddViews.swift

extension ViewStateProtocol where Self: UIViewController {
    ..........
     // Manages and adds different views on the basis of the state
    func addView(withState state: StatesType) {
        
        // error state, empty state & loading state
        switch state {
        case .loading:
            // calls state manager to add a laoding view
            stateManager?.addView(loadingView!, forState: StatesType.loading.rawValue, superview: view)
        case .error:
            // calls state manager to add an error view
            stateManager?.addView(errorView!, forState: StatesType.error.rawValue, superview: view)
        case .empty:
            // calls state manager to add an empty view
            stateManager?.addView(emptyView!, forState: StatesType.empty.rawValue, superview: view)
        default:
            // removes all the views for managing states
            removeAllViews()
        }
    }
}