Testing ViewModels - Testing in Android - Part 10

In this video you will learn how you can test your ViewModels in Android with the help of a fake repository.

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[aritrabhattacharya]

Give this guy a nobel already. Outstanding work!!

[elijahonduso]

Since I discovered this channel, my life has never been the same again. Excellent!

[slaviboy]

At 1:52 The ShoppingDao is interface so we can make FakeShoppingDao class and implement the methods and then return fake data from their method, the same is for the PixabeyAPI it is also an interface, so we should make FakePixabeyAPI class and return fake api response. So we should make two separate tests
1) When we test the ViewModel we should use the same logic as you did and create FakeShoppingRepository
2) Create separate test for the DefaultShoppingRepository class using the FakeShopingDao and FakePixabeyAPI classes, that way we can test the logic inside the class

dependencies
The idea is that we should mainly use interfaces, and inject the classes using Hilt or Dagger, that way our tests are not depending on any other classes that we should pass to the constructor

[damilolaomoyiwola]

This is great! Thank you, Philipp! ❤️ Your tutorial playlist has been a life-saver for testing in Android.

[sbane]

Thank you so much philipp! i was struggling so much with the concept of testing as long as i could remember, I'm so happy i found your channel <3

[iftak]

Stop one of the greatest Android channel :) never forget 😉

[haykmkrtchyan]

Regarding setValue() and postValue() of LiveData the key difference is in which thread we call them. If we are in a background thread, we need to use postValue(). If we are in the main thread we can call directly setValue().

[mehedihasansarik]

I just like all of your videos before I watch it, you are awesome bro and I think you deserve the most subscribers, anyway keep it up and help the developer from worldwide.

[AwesomeDevNotes]

I am crying. The topics selected are so helpful

[fausto]

Thats a very interesting approach. You keeped it simple and well explained just like in the other videos, thank you very much!

[krutz]

Great video, surely a bit outdated but anyone can manage to replace the deprecated stuff

[funnymoviemomen]

Great tutorial on such an important subject. Thank you!

[hoonjung]

Again and again. Great content! Well explained!

[mtrx]

First of all thank you for your great work!!! :)
Maybe you can give a quick answer to the following question:
As I can see there’s some work needed to change the dispatcher and to mock the db and API calls. What are the reasons why the view mode test should not be put in the android test folder ? I am just thinking if it was in the Android Testfolder, the circuit es of the viewModel can be used and for the db an InMemoryDB can be set up. So from my point of view this would be a more realistic approach on the view model test and would finally also cover some the database transactions related to the view mode... Is it maybe the independence of the test cases that would require them to not use the actual database and coroutines?

[fahrican]

great video, was looking for MainCoroutineRule a long time

[bro_chenzox]

Thank you very much for the lesson! It's awesome!
Now I found that if I test id what initial number should it has:
@Test
fun `correct id is returned after add first shopping item, returns success`() {

viewModel.insertShoppingItem("name", "5", "3.0")


}

it shouldn't be a null as we've mentioned earlier in the ShoppingItem data class, but can be 0 or 1 or any Int we want to start our list from.

[akashdeepwadhwa]

thank you for wonderful tutorial and in life only your videos making me complete my homework ..lol

[gajendrapandeya]

Yeah
Finally I'm the first viewer

[amirdaryabak]

Philipp thank you for this awesome course and you teach us really good , but can you tell me what document is good to read beside your course? thank you.

[cleawrence]

Great video but in MainCouroutineRule some functions are deprecated we have to migrate to news declarations