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Исправлен недочёт с toolbar
Удалены лишние пробелы

app/src/main/java/com/example/movieapp/BindingAdapter.kt

@@ -11,6 +11,7 @@ import com.bumptech.glide.request.RequestOptions
 import com.example.movieapp.domain.Movie
 import com.example.movieapp.overview.MovieAdapter
 
+//Binding adapter used to display images from URL using Glide
 @BindingAdapter("imageUrl")
 fun bindImage(imageView: ImageView, imgUrl: String?) {
     imgUrl?.let {
@@ -26,34 +27,40 @@ fun bindImage(imageView: ImageView, imgUrl: String?) {
     }
 }
 
+//Binding adapter used to display title from object
 @BindingAdapter("title")
 fun bindTitle(textView: TextView, title: String?) {
     title?.let {
         textView.text = title
     }
 }
 
+//Binding adapter used to display plot from object
 @BindingAdapter("plot")
 fun TextView.bindPlot(plot: String?) {
     plot?.let {
         text = plot
     }
 }
 
+//Binding adapter used to display year from object
 @BindingAdapter("year")
 fun TextView.bindYear(year: Int?) {
     year?.let {
         text = year.toString()
     }
 }
 
+//Binding adapter used to set adapter of RecyclerView
 @BindingAdapter("listData")
 fun bindRecyclerView(recyclerView: RecyclerView, data: List<Movie>?) {
-    val adapter = recyclerView.adapter as MovieAdapter
-    adapter.submitList(data)
+    data?.let {
+        val adapter = recyclerView.adapter as MovieAdapter
+        adapter.submitList(data)
+    }
 }
 
-
+//Binding adapter used to hide the spinner once data is available.
 @BindingAdapter("isNetworkError", "playlist")
 fun hideIfNetworkError(view: View, isNetWorkError: Boolean, playlist: Any?) {
     view.visibility = if (playlist != null) View.GONE else View.VISIBLE

app/src/main/java/com/example/movieapp/MainActivity.kt

@@ -9,6 +9,8 @@ class MainActivity : AppCompatActivity() {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_main)
+
+        //Function for Light-Dark theme
         AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.getDefaultNightMode())
     }
 }

app/src/main/java/com/example/movieapp/detail/DetailFragment.kt

@@ -49,6 +49,4 @@ class DetailFragment : Fragment() {
 
         return binding.root
     }
-
-
 }

app/src/main/java/com/example/movieapp/detail/DetailViewModelFactory.kt

@@ -5,11 +5,11 @@ import androidx.lifecycle.ViewModelProvider
 import com.example.movieapp.domain.Movie
 
 class DetailViewModelFactory(private val movie: Movie) : ViewModelProvider.Factory {
+    @Suppress("UNCHECKED_CAST")
     override fun <T : ViewModel?> create(modelClass: Class<T>): T {
         if (modelClass.isAssignableFrom(DetailViewModel::class.java)) {
             return DetailViewModel(movie) as T
         }
         throw IllegalArgumentException("Unknown ViewModel class")
     }
-
 }

app/src/main/java/com/example/movieapp/network/MovieApiService.kt

@@ -7,11 +7,14 @@ import retrofit2.http.GET
 
 private const val BASE_URL = "https://api.myjson.com/bins/"
 
+//A retrofit service to fetch movie playlist.
 interface MovieApiService {
     @GET("19tvhm")
     suspend fun getPropertyAsync(): List<MovieProperty>
 }
 
+
+//Main entry point for network access
 object MovieApi {
 
     private val retrofit = Retrofit.Builder()

app/src/main/java/com/example/movieapp/network/MovieProperty.kt

@@ -4,9 +4,7 @@ import com.example.movieapp.database.DatabaseMovie
 import com.squareup.moshi.Json
 import com.squareup.moshi.JsonClass
 
-
-
-//
+//Network object of movie for REST
 @JsonClass(generateAdapter = true)
 data class MovieProperty(
     @Json(name = "imdbID") val id: String,

app/src/main/java/com/example/movieapp/overview/MovieAdapter.kt

@@ -11,7 +11,6 @@ import com.example.movieapp.domain.Movie
 class MovieAdapter(private val onClickListener: ClickListener) :
     ListAdapter<Movie, MovieAdapter.MovieViewHolder>(DiffCallback()) {
 
-
     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MovieViewHolder {
         return MovieViewHolder(
             ItemBinding.inflate(
@@ -28,14 +27,15 @@ class MovieAdapter(private val onClickListener: ClickListener) :
         holder.bind(item)
     }
 
-    class MovieViewHolder(private val binding: ItemBinding) :
-        RecyclerView.ViewHolder(binding.root) {
+    class MovieViewHolder(private val binding: ItemBinding) : RecyclerView.ViewHolder(binding.root) {
         fun bind(movie: Movie) {
             binding.movie = movie
             binding.executePendingBindings()
         }
     }
 
+
+    //Class for comparing the old list and the new one, and updating it
     class DiffCallback : DiffUtil.ItemCallback<Movie>() {
         override fun areItemsTheSame(oldItem: Movie, newItem: Movie): Boolean {
             return oldItem == newItem
@@ -44,10 +44,9 @@ class MovieAdapter(private val onClickListener: ClickListener) :
         override fun areContentsTheSame(oldItem: Movie, newItem: Movie): Boolean {
             return newItem.id == oldItem.id
         }
-
     }
 
-
+    //Class for click by element
     class ClickListener(val clickListener: (movie: Movie) -> Unit) {
         fun onClick(movie: Movie) = clickListener(movie)
     }

app/src/main/java/com/example/movieapp/overview/OverviewFragment.kt

@@ -14,48 +14,57 @@ import com.example.movieapp.databinding.OverviewFragmentBinding
 
 class OverviewFragment : Fragment() {
 
-
     private val viewModel: OverviewViewModel by lazy {
         val activity = requireNotNull(this.activity) {}
         ViewModelProvider(this, OverviewViewModelFactory(activity.application))
             .get(OverviewViewModel::class.java)
     }
 
-
     override fun onCreateView(
         inflater: LayoutInflater, container: ViewGroup?,
         savedInstanceState: Bundle?
     ): View? {
 
         val binding = OverviewFragmentBinding.inflate(inflater)
-        val myToolbar = binding.myToolbar
-        (activity as AppCompatActivity).setSupportActionBar(myToolbar)
 
+        //Toolbar
+        val myToolbar = binding.myToolbar
 
-        binding.lifecycleOwner = viewLifecycleOwner
+        (activity as AppCompatActivity).apply {
+            setSupportActionBar(myToolbar)
+            title = "Movie App"
+        }
 
-        binding.viewModel = viewModel
 
+        //Listener of recycler view click
         binding.recycler.adapter = MovieAdapter(MovieAdapter.ClickListener {
             viewModel.displayPropertyDetails(it)
         })
 
+        //Navigate to Detail Activity
         viewModel.navigateToSelectProperty.observe(viewLifecycleOwner, Observer {
             if (it != null) {
                 this.findNavController()
                     .navigate(OverviewFragmentDirections.actionOverviewFragmentToDetailFragment(it))
-                viewModel.displayPropertyDetailsComlited()
+                viewModel.displayPropertyDetailsCompleted()
             }
-
         })
 
-        viewModel.eventNetworkError.observe(viewLifecycleOwner, Observer<Boolean> { isNetworkError ->
+        //Looking for the internet connection
+        viewModel.eventNetworkError.observe(
+            viewLifecycleOwner,
+            Observer<Boolean> { isNetworkError ->
                 if (isNetworkError) onNetworkError()
             })
 
+        binding.lifecycleOwner = viewLifecycleOwner
+        binding.viewModel = viewModel
+
         return binding.root
     }
 
+
+    //Function will show a toast when there is no internet
     private fun onNetworkError() {
         if (!viewModel.isNetworkErrorShown.value!!) {
             Toast.makeText(activity, "Network error", Toast.LENGTH_LONG).show()

app/src/main/java/com/example/movieapp/overview/OverviewViewModel.kt

@@ -13,28 +13,29 @@ import kotlinx.coroutines.launch
 
 class OverviewViewModel(application: Application) : ViewModel() {
 
+    //LiveData object of movie
     private val _navigateToSelectProperty = MutableLiveData<Movie>()
     val navigateToSelectProperty: LiveData<Movie>
         get() = _navigateToSelectProperty
 
+    //LiveData for show Progress Bar
     private var _eventNetworkError = MutableLiveData<Boolean>(false)
     val eventNetworkError: LiveData<Boolean>
         get() = _eventNetworkError
 
+    //LiveData for show internet error
     private var _isNetworkErrorShown = MutableLiveData<Boolean>(false)
     val isNetworkErrorShown: LiveData<Boolean>
         get() = _isNetworkErrorShown
 
-
     private val moviesRepository = MoviesRepository(getDatabase(application))
     val playList = moviesRepository.movies
 
     init {
-        getMovieListProperty()
+        getMovieList()
     }
 
-
-    private fun getMovieListProperty() {
+    private fun getMovieList() {
         viewModelScope.launch {
             try {
                 moviesRepository.refreshMovie()
@@ -52,13 +53,11 @@ class OverviewViewModel(application: Application) : ViewModel() {
         _navigateToSelectProperty.value = movie
     }
 
-    fun displayPropertyDetailsComlited() {
+    fun displayPropertyDetailsCompleted() {
         _navigateToSelectProperty.value = null
     }
 
     fun onNetworkErrorShown() {
         _isNetworkErrorShown.value = true
     }
-
-
 }

app/src/main/java/com/example/movieapp/overview/OverviewViewModelFactory.kt

@@ -4,10 +4,11 @@ import android.app.Application
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.ViewModelProvider
 
-class OverviewViewModelFactory(private val application: Application) : ViewModelProvider.Factory {
+class OverviewViewModelFactory(private val app: Application) : ViewModelProvider.Factory {
+    @Suppress("UNCHECKED_CAST")
     override fun <T : ViewModel?> create(modelClass: Class<T>): T {
         if (modelClass.isAssignableFrom(OverviewViewModel::class.java)) {
-            return OverviewViewModel(application) as T
+            return OverviewViewModel(app) as T
         }
         throw ExceptionInInitializerError("Unknown viewModel Class")
     }

app/src/main/java/com/example/movieapp/repository/MoviesRepository.kt

@@ -12,13 +12,15 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
 
 class MoviesRepository(private val movieDatabase: MovieDatabase) {
+    //Refresh the videos stored in the offline cache.
     suspend fun refreshMovie() {
         withContext(Dispatchers.IO) {
             val playList = MovieApi.retrofitService.getPropertyAsync()
             movieDatabase.movieDao.insert(playList.asDatabaseModal())
         }
     }
 
+    //Transformation database object to movie object
     val movies: LiveData<List<Movie>> = Transformations.map(movieDatabase.movieDao.getMovies()) {
         it.asDomainModel()
     }