When you compare this piece of code, to the normal way of setting up the data source and implementing all the tableView delegate functions, which one do you feel is easier? The first thing to do is to present the loading indicator to the user whenever we are calling this function. Next we'll call the subscribe to start listening to the events, and finally, we'll set the disposeBag to dispose the observable. I wrote the app using MVVM without RxSwift 18 months ago. Also the value only is only changed when a new request to server is completed. I wrote the app using MVVM without RxSwift 1,5 years ago. Now, I thought it would be nice to refactor it and see how it looks like when using RxSwift with MVVM. So what do you think? Next, let’s check the bindViewModel() function: At first, we’ll bind the friendCells to tableview. In the viewDidLoad, we'll call the preparing functions: First, we’ll prepare the view model by binding all the values in the bindViewModel(). So in general, we have: 1. View Controller: It only performs things related to UI – Show/get information. If you have any questions, comments or feedback, you can comment below or contact me on Twitter! We could do it by the same way we were listening to the observable states when receiving friends from the network client. thank you. At the bottom of the code block you can see two variables that are defined as BehaviorRelay. they're used to gather information about the pages you visit and how many clicks you need to accomplish a task. .disposed(by: disposeBag) In case you want to learn the basics of the MVVM pattern, I suggest that you check out my earlier post, I’ll cover these topics by showing how to write an application called Friends. At the beginning of the class, we’ll notice the view model definition. I use ‘loadInProgress’ and ‘onShowLoadingHud’ because I think loading is a specific view model action that view controller does not need to know about. Whenever the delete event gets called for the table view, also the modelDeleted gets called. In case you want to know the basics of MVVM pattern, I suggest that you check out my older post MVVM with Swift application. We’ll also add all the libs for the testing targets that we have. I wrote the app using MVVM without RxSwift 1,5 years ago. Let’s start with the viewModel. This way there is no change that the value is accidentally changed in the view controller side. At first, we’ll import RxSwift so that we have the tools provided by the library available for use. I am Max, and I am going to talk to you about MVVM with RxSwift. In the empty cell's case, we'll do the same as with the error case, with the exception that we'll use hard coded "No data available" as the textLabel?.text. For example: we tie firstnameValid with firstname. So inside the view model, we define our own disposeBag. In Samsara, a profile is the model that encapsulates the settings for a meditation session. View Model: It receives information from VC, handles all this information and sends it back to VC. I’d love to follow ReusabilityPrinciple while building our app. Hey! So using PublishSubjectis very similar to using variables, but instead of setting the value, we’ll call onNext() instead. Selecting a cell is done with modelSelected and the handling is very close to cell deleting. Thanks, I am glad you find the post helpful. Now that we have handled the data source and delegation of the tableView, all that is left is to make sure that this observable is disposed using the disposeBag when the view is deallocated. Friends is an iPhone app that downloads a list of friends and displays them in the app. This blog post discusses tokens and their implementation considerations used by OAuth 2.0 and OpenID Connect protocols. This simple app displays a list of the most starred repositories on GitHub by a language. Whenever the delete event gets called for the tableView, also the modelDeleted gets called. PublishSubjectreceives information and then publishes it to the subscriber. The example project is in the MVVM-Rx folder. I have implemented the cell clicking and deleting a friend is done using the swipe. OAuth 2.0 and OIDC: what should I know about tokens? Just making sure that you did checkout the RxSwift branch from GitHub? So inside the function, we'll just check that the cell type is what we expect, and call the viewModel.delete function with the correct ViewModel as a parameter. Then, we’ll use switch to check if the element contains .normal, .error or .empty cells. This enum contains all the cell types our table view can show. I do have quite a few things on my topic list so I can’t promise(Kit) you that I’ll do it any time soon.. It is a great and detailed post for new to understand. How cool is this! Variable is a type provided by RxSwift. It is a computed property and it returns an observable for the cells variable. A user can tap on a button in the navigation bar to show the second screen. Now that we have handled the data source and delegation of the tableView, all that is left is to make sure that this observable is disposed of using the disposeBag, when View is deallocated. We use FriendViewController to create a new friend and also to update an old one. Yes, you can of course do this using only one variable. In the normal case, we’ll deque the cell from the tableView and set the viewModel received as the cells viewModel. It is also defined as private, just as the cells variable we discussed above. return loadInProgress RxSwift has been a hot topic in the swift community for a few years now, but somehow I’ve managed to avoid it. Now, let’s check the onShowError which is defined as a PublishSubject. I also had some trouble at first to figure out when to use Variable, Observable, PublishSubject and how I should bind values to UI components. All the codes are available, but I’ll dive into the network layer in another post. And after we are done editing the Podfile, we’ll need to run pod install in the terminal. In the MVVM design pattern, Model is the same as in MVC pattern. This is the variable that we'll use later on the view controller side to bind the cell value to the tableView. After that, we'll call getFriends() from the appServerClient and subscribe to the observable it returns. Network request with RxSwift. Error cell show error information to the user and empty cell is shown when there is no data on the server. We can directly define the blocks for different states, as we’ve done above. 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