# Unit Test - 使用hilt測試9 - Testing Add Item

---

## 開始吧

### 情境

### 修改AddShoppingItemFragmen
* 注入glide
* 觀察者模式-當url變化.用glide讀取，insert data 做對應的動作

class AddShoppingItemFragment @Inject constructor(
    val glide: RequestManager //注入glide
) : Fragment(R.layout.fragment_add_shopping_item) {

    lateinit var viewModel: ShoppingViewModel

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        viewModel = ViewModelProvider(requireActivity()).get(ShoppingViewModel::class.java)
        subscribeToObserver()

        btnAddShoppingItem.setOnClickListener {
            viewModel.insertShoppingItem(
                etShoppingItemName.text.toString(),
                etShoppingItemAmount.text.toString(),
                etShoppingItemPrice.text.toString()
            )
        }

        ivShoppingImage.setOnClickListener {
            findNavController().navigate(
                AddShoppingItemFragmentDirections.actionAddShoppingItemFragmentToImagePickFragment()
            )
        }

        val callback = object : OnBackPressedCallback(true) {
            override fun handleOnBackPressed() {
                viewModel.setCurImageUrl("")
                findNavController().popBackStack()
            }
        }
        requireActivity().onBackPressedDispatcher.addCallback(callback)
    }

    private fun subscribeToObserver() {
        viewModel.curImageUrl.observe(viewLifecycleOwner, Observer {
            glide.load(it).into(ivShoppingImage)
        })

        viewModel.insertShoppingItemStatus.observe(viewLifecycleOwner, Observer {
            it.getContentIfNotHandled()?.let { result ->
                when (result.status) {
                    Status.SUCCESS -> {
                        Snackbar.make(
                            requireActivity().rootLayout,
                            "Add Shopping Item",
                            Snackbar.LENGTH_LONG
                        ).show()
                        findNavController().popBackStack()
                    }
                    Status.ERROR -> {
                        Snackbar.make(
                            requireActivity().rootLayout,
                            result.message ?: "an unknown error occurred",
                            Snackbar.LENGTH_LONG
                        ).show()
                    }
                    Status.LOADING -> {
                        /* NO-OP */
                    }
                }
            }
        })
    }
}

### 修正ShoppingFragmentFactory
* 增加glide的參數

class ShoppingFragmentFactory @Inject constructor(
    private val imageAdapter: ImageAdapter,
    private val glide: RequestManager //注入用的
) : FragmentFactory() {

    override fun instantiate(classLoader: ClassLoader, className: String): Fragment {
        return when (className) {
            ImagePickFragment::class.java.name -> ImagePickFragment(imageAdapter)
            //當實例化的fragment是底下這個，要傳遞glide做實例化
            AddShoppingItemFragmen::class.java.name -> AddShoppingItemFragmen(glide)
            else -> super.instantiate(classLoader, className)
        }
    }
}

### 寫測試吧
* 打開之前的AddShoppingItemFragmentTest
* 寫入一筆資料，並查詢DB是否有該筆資料

@ExperimentalCoroutinesApi
@MediumTest
@HiltAndroidTest
class AddShoppingItemFragmentTest {

    @get:Rule
    var hiltRule = HiltAndroidRule(this)

    @get:Rule
    var instantTaskExecutorRule = InstantTaskExecutorRule()

    @Before
    fun setup() {
        hiltRule.inject()
    }

    //新增factory
    @Inject
    lateinit var fragmentFactory: ShoppingFragmentFactory
    //新增測試
    @Test
    fun clickInsertIntoDb_shoppingItemInsertedIntoDb() {
        val testViewModel = ShoppingViewModel(FakeRepository())
        launchFragmentInHiltContainer<AddShoppingItemFragment>(
            fragmentFactory = fragmentFactory
        ) {
            viewModel = testViewModel
        }

        onView(withId(R.id.etShoppingItemName)).perform(replaceText("shopping item"))
        onView(withId(R.id.etShoppingItemAmount)).perform(replaceText("5"))
        onView(withId(R.id.etShoppingItemPrice)).perform(replaceText("5.5"))
        onView(withId(R.id.btnAddShoppingItem)).perform(click())

        assertThat(testViewModel.shoppingItems.getOrAwaitValue())
            .contains(ShoppingItem("shopping item", 5, 5.5f, ""))

    }

    @Test
    fun pressBackButton_popBackStack() {
        val navController = mock(NavController::class.java)
        launchFragmentInHiltContainer<AddShoppingItemFragment> {
            Navigation.setViewNavController(requireView(), navController)
        }

        pressBack()
        verify(navController).popBackStack()
    }

    @Test
    fun clickivShoppingImage_navigeteToImagePickFragment() {
        val navController = mock(NavController::class.java)
        launchFragmentInHiltContainer<AddShoppingItemFragment> {
            Navigation.setViewNavController(requireView(), navController)
        }

        onView(withId(R.id.ivShoppingImage)).perform(click())

        verify(navController).navigate(
            AddShoppingItemFragmentDirections.actionAddShoppingItemFragmentToImagePickFragment()
        )
    }

    @Test
    fun imageUrlIsEmpty_afterPooBackStack() {
        val testviewModel = ShoppingViewModel(FakeRepository())

        val navController = mock(NavController::class.java)
        launchFragmentInHiltContainer<AddShoppingItemFragment> {
            Navigation.setViewNavController(requireView(), navController)
            viewModel = testviewModel
        }
        pressBack()
        val value = testviewModel.curImageUrl.getOrAwaitValue()
        assertThat(value).isEmpty()

    }
}


參考資料
[
Philipp Lackner's channel](https://www.youtube.com/watch?v=6ZQ9v0KFiPA)

###### tags: `test` `Unit Test` `kotlin` `hilt`