[코드랩] Feature internet filter

GuessTheWord-Starter/app/build.gradle

@@ -56,4 +56,7 @@ dependencies {
     // Navigation
     implementation "androidx.navigation:navigation-fragment-ktx:2.3.0"
     implementation "androidx.navigation:navigation-ui-ktx:2.3.0"
+
+    //ViewModel
+    implementation 'androidx.lifecycle:lifecycle-viewmodel-ktx:2.2.0'
 }

GuessTheWord-Starter/app/src/main/java/com/example/android/guesstheword/screens/game/GameFragment.kt

@@ -17,11 +17,15 @@
 package com.example.android.guesstheword.screens.game
 
 import android.os.Bundle
+import android.util.Log
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
+import android.widget.Toast
 import androidx.databinding.DataBindingUtil
 import androidx.fragment.app.Fragment
+import androidx.lifecycle.ViewModelProvider
+import androidx.navigation.fragment.NavHostFragment
 import com.example.android.guesstheword.R
 import com.example.android.guesstheword.databinding.GameFragmentBinding
 
@@ -30,17 +34,10 @@ import com.example.android.guesstheword.databinding.GameFragmentBinding
  */
 class GameFragment : Fragment() {
 
-    // The current word
-    private var word = ""
-
-    // The current score
-    private var score = 0
-
-    // The list of words - the front of the list is the next word to guess
-    private lateinit var wordList: MutableList<String>
-
     private lateinit var binding: GameFragmentBinding
 
+    private lateinit var viewModel: GameViewModel
+
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
                               savedInstanceState: Bundle?): View? {
 
@@ -52,79 +49,49 @@ class GameFragment : Fragment() {
                 false
         )
 
-        resetList()
-        nextWord()
+        Log.i("GameFragment", "Called ViewModelProvider.get")
+        viewModel = ViewModelProvider(this).get(GameViewModel::class.java)
 
         binding.correctButton.setOnClickListener { onCorrect() }
         binding.skipButton.setOnClickListener { onSkip() }
+        binding.endGameButton.setOnClickListener { onEndGame() }
         updateScoreText()
         updateWordText()
         return binding.root
 
     }
 
-    /**
-     * Resets the list of words and randomizes the order
-     */
-    private fun resetList() {
-        wordList = mutableListOf(
-                "queen",
-                "hospital",
-                "basketball",
-                "cat",
-                "change",
-                "snail",
-                "soup",
-                "calendar",
-                "sad",
-                "desk",
-                "guitar",
-                "home",
-                "railway",
-                "zebra",
-                "jelly",
-                "car",
-                "crow",
-                "trade",
-                "bag",
-                "roll",
-                "bubble"
-        )
-        wordList.shuffle()
-    }
-
-    /** Methods for buttons presses **/
+    /** Methods for button click handlers **/
 
     private fun onSkip() {
-        score--
-        nextWord()
+        viewModel.onSkip()
+        updateWordText()
+        updateScoreText()
     }
 
     private fun onCorrect() {
-        score++
-        nextWord()
-    }
-
-    /**
-     * Moves to the next word in the list
-     */
-    private fun nextWord() {
-        if (!wordList.isEmpty()) {
-            //Select and remove a word from the list
-            word = wordList.removeAt(0)
-        }
+        viewModel.onCorrect()
         updateWordText()
         updateScoreText()
     }
 
-
     /** Methods for updating the UI **/
-
     private fun updateWordText() {
-        binding.wordText.text = word
+        binding.wordText.text = viewModel.word
     }
 
     private fun updateScoreText() {
-        binding.scoreText.text = score.toString()
+        binding.scoreText.text = viewModel.score.toString()
+    }
+
+    private fun onEndGame() {
+        gameFinished()
+    }
+
+    private fun gameFinished() {
+        Toast.makeText(activity, "Game has just finished", Toast.LENGTH_SHORT).show()
+        val action = GameFragmentDirections.actionGameToScore()
+        action.score = viewModel.score
+        NavHostFragment.findNavController(this).navigate(action)
     }
 }

GuessTheWord-Starter/app/src/main/java/com/example/android/guesstheword/screens/game/GameViewModel.kt

@@ -0,0 +1,80 @@
+package com.example.android.guesstheword.screens.game
+
+import android.util.Log
+import androidx.lifecycle.ViewModel
+
+class GameViewModel : ViewModel() {
+
+    // The current word
+    var word = ""
+
+    // The current score
+    var score = 0
+
+    // The list of words - the front of the list is the next word to guess
+    private lateinit var wordList: MutableList<String>
+
+    /**
+     * Resets the list of words and randomizes the order
+     */
+    fun resetList() {
+        wordList = mutableListOf(
+            "queen",
+            "hospital",
+            "basketball",
+            "cat",
+            "change",
+            "snail",
+            "soup",
+            "calendar",
+            "sad",
+            "desk",
+            "guitar",
+            "home",
+            "railway",
+            "zebra",
+            "jelly",
+            "car",
+            "crow",
+            "trade",
+            "bag",
+            "roll",
+            "bubble"
+        )
+        wordList.shuffle()
+    }
+
+
+    init {
+        resetList()
+        nextWord()
+        Log.i("GameViewModel", "GameViewModel created!")
+    }
+
+    /**
+     * Moves to the next word in the list
+     */
+    private fun nextWord() {
+        if (!wordList.isEmpty()) {
+            //Select and remove a word from the list
+            word = wordList.removeAt(0)
+        }
+
+    }
+
+    /** Methods for buttons presses **/
+    fun onSkip() {
+        score--
+        nextWord()
+    }
+
+    fun onCorrect() {
+        score++
+        nextWord()
+    }
+
+    override fun onCleared() {
+        super.onCleared()
+        Log.i("GameViewModel", "GameViewModel destroyed!!")
+    }
+}

GuessTheWord-Starter/app/src/main/java/com/example/android/guesstheword/screens/score/ScoreFragment.kt

@@ -22,6 +22,7 @@ import android.view.View
 import android.view.ViewGroup
 import androidx.databinding.DataBindingUtil
 import androidx.fragment.app.Fragment
+import androidx.lifecycle.ViewModelProvider
 import androidx.navigation.fragment.navArgs
 import com.example.android.guesstheword.R
 import com.example.android.guesstheword.databinding.ScoreFragmentBinding
@@ -31,6 +32,9 @@ import com.example.android.guesstheword.databinding.ScoreFragmentBinding
  */
 class ScoreFragment : Fragment() {
 
+    private lateinit var viewModel: ScoreViewModel
+    private lateinit var viewModelFactory: ScoreViewModelFactory
+
     override fun onCreateView(
             inflater: LayoutInflater,
             container: ViewGroup?,
@@ -45,6 +49,10 @@ class ScoreFragment : Fragment() {
                 false
         )
 
+        viewModelFactory = ScoreViewModelFactory(ScoreFragmentArgs.fromBundle(requireArguments()).score)
+        viewModel = ViewModelProvider(this, viewModelFactory).get(ScoreViewModel::class.java)
+
+        binding.scoreText.text = viewModel.score.toString()
         return binding.root
     }
 }

GuessTheWord-Starter/app/src/main/java/com/example/android/guesstheword/screens/score/ScoreViewModel.kt

@@ -0,0 +1,13 @@
+package com.example.android.guesstheword.screens.score
+
+import android.util.Log
+import androidx.lifecycle.ViewModel
+
+class ScoreViewModel(finalScore: Int) : ViewModel() {
+    // The final score
+    var score = finalScore
+
+    init {
+        Log.i("ScoreViewModel", "Final score is $finalScore")
+    }
+}

GuessTheWord-Starter/app/src/main/java/com/example/android/guesstheword/screens/score/ScoreViewModelFactory.kt

@@ -0,0 +1,14 @@
+package com.example.android.guesstheword.screens.score
+
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.ViewModelProvider
+
+class ScoreViewModelFactory(private val finalScore: Int) : ViewModelProvider.Factory {
+
+    override fun <T : ViewModel?> create(modelClass: Class<T>): T {
+        if(modelClass.isAssignableFrom(ScoreViewModel::class.java)) {
+            return ScoreViewModel(finalScore) as T
+        }
+        throw IllegalArgumentException("Unknown ViewModel class")
+    }
+}

MarsRealEstate-Starter/app/build.gradle

@@ -39,6 +39,15 @@ android {
     buildFeatures {
         dataBinding true
     }
+
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+
+    kotlinOptions {
+        jvmTarget = JavaVersion.VERSION_1_8.toString()
+    }
 }
 
 dependencies {
@@ -59,4 +68,15 @@ dependencies {
 
     // Core with Ktx
     implementation "androidx.core:core-ktx:$version_core"
+
+    // Retrofit
+    implementation "com.squareup.retrofit2:retrofit:$version_retrofit"
+    implementation "com.squareup.retrofit2:converter-scalars:$version_retrofit"
+
+    implementation "com.squareup.moshi:moshi-kotlin:$version_moshi"
+    implementation "com.squareup.retrofit2:retrofit:$version_retrofit"
+    implementation "com.squareup.retrofit2:converter-scalars:$version_retrofit"
+    implementation "com.squareup.retrofit2:converter-moshi:$version_retrofit"
+
+    implementation "com.github.bumptech.glide:glide:$version_glide"
 }

MarsRealEstate-Starter/app/src/main/AndroidManifest.xml

@@ -19,6 +19,8 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.example.android.marsrealestate">
 
+    <uses-permission android:name="android.permission.INTERNET" />
+
     <application
         android:allowBackup="true"
         android:icon="@mipmap/ic_launcher"

MarsRealEstate-Starter/app/src/main/java/com/example/android/marsrealestate/BindingAdapters.kt

@@ -17,3 +17,54 @@
 
 package com.example.android.marsrealestate
 
+import android.view.View
+import android.widget.ImageView
+import androidx.core.net.toUri
+import androidx.databinding.BindingAdapter
+import androidx.recyclerview.widget.RecyclerView
+import com.bumptech.glide.Glide
+import com.bumptech.glide.request.RequestOptions
+import com.example.android.marsrealestate.network.MarsProperty
+import com.example.android.marsrealestate.overview.MarsApiStatus
+import com.example.android.marsrealestate.overview.PhotoGridAdapter
+
+@BindingAdapter("imageUrl")
+fun ImageView.bindImage(imgUrl: String?) {
+    imgUrl?.let {
+        val imgUri = it.toUri().buildUpon().scheme("https").build()
+        Glide.with(this.context)
+            .load(imgUri)
+            .apply(
+                RequestOptions()
+                    .placeholder(R.drawable.loading_animation)
+                    .error(R.drawable.ic_broken_image)
+            )
+            .into(this)
+    }
+}
+
+/**
+ * When there is no Mars property data (data is null), hide the [RecyclerView], otherwise show it.
+ */
+@BindingAdapter("listData")
+fun bindRecyclerView(recyclerView: RecyclerView, data: List<MarsProperty>?) {
+    val adapter = recyclerView.adapter as PhotoGridAdapter
+    adapter.submitList(data)
+}
+
+@BindingAdapter("marsApiStatus")
+fun bindStatus(statusImageView: ImageView, status: MarsApiStatus?) {
+    when (status) {
+        MarsApiStatus.LOADING -> {
+            statusImageView.visibility = View.VISIBLE
+            statusImageView.setImageResource(R.drawable.loading_animation)
+        }
+        MarsApiStatus.ERROR -> {
+            statusImageView.visibility = View.VISIBLE
+            statusImageView.setImageResource(R.drawable.ic_connection_error)
+        }
+        MarsApiStatus.DONE -> {
+            statusImageView.visibility = View.GONE
+        }
+    }
+}

MarsRealEstate-Starter/app/src/main/java/com/example/android/marsrealestate/detail/DetailFragment.kt

@@ -21,19 +21,30 @@ import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
 import androidx.fragment.app.Fragment
+import androidx.lifecycle.ViewModelProvider
 import com.example.android.marsrealestate.databinding.FragmentDetailBinding
 
 /**
  * This [Fragment] will show the detailed information about a selected piece of Mars real estate.
  */
 class DetailFragment : Fragment() {
-    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
-                              savedInstanceState: Bundle?): View? {
+
+    override fun onCreateView(
+        inflater: LayoutInflater, container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
 
         @Suppress("UNUSED_VARIABLE")
         val application = requireNotNull(activity).application
         val binding = FragmentDetailBinding.inflate(inflater)
         binding.lifecycleOwner = this
+
+        val marsProperty = DetailFragmentArgs.fromBundle(arguments!!).selectedProperty
+        val viewModelFactory = DetailViewModelFactory(marsProperty, application)
+        binding.viewModel = ViewModelProvider(
+            this, viewModelFactory
+        ).get(DetailViewModel::class.java)
+
         return binding.root
     }
 }

MarsRealEstate-Starter/app/src/main/java/com/example/android/marsrealestate/detail/DetailViewModel.kt

@@ -17,12 +17,38 @@
 package com.example.android.marsrealestate.detail
 
 import android.app.Application
-import androidx.lifecycle.AndroidViewModel
-import androidx.lifecycle.ViewModel
+import androidx.lifecycle.*
 import com.example.android.marsrealestate.network.MarsProperty
+import com.example.android.marsrealestate.R
 
 /**
  * The [ViewModel] that is associated with the [DetailFragment].
  */
-class DetailViewModel(@Suppress("UNUSED_PARAMETER")marsProperty: MarsProperty, app: Application) : AndroidViewModel(app) {
+class DetailViewModel(@Suppress("UNUSED_PARAMETER") marsProperty: MarsProperty, app: Application) :
+    AndroidViewModel(app) {
+
+    private val _selectedProperty = MutableLiveData<MarsProperty>()
+    val selectedProperty: LiveData<MarsProperty>
+        get() = _selectedProperty
+
+    val displayPropertyPrice = Transformations.map(selectedProperty) {
+        app.applicationContext.getString(
+            when (it.isRental) {
+                true -> R.string.display_price_monthly_rental
+                false -> R.string.display_price
+            }, it.price)
+    }
+
+    val displayPropertyType = Transformations.map(selectedProperty) {
+        app.applicationContext.getString(R.string.display_type,
+            app.applicationContext.getString(
+                when (it.isRental) {
+                    true -> R.string.type_rent
+                    false -> R.string.type_sale
+                }))
+    }
+
+    init {
+        _selectedProperty.value = marsProperty
+    }
 }

MarsRealEstate-Starter/app/src/main/java/com/example/android/marsrealestate/network/MarsApiService.kt

@@ -17,4 +17,38 @@
 
 package com.example.android.marsrealestate.network
 
-private const val BASE_URL = "https://android-kotlin-fun-mars-server.appspot.com/"
+import com.squareup.moshi.Moshi
+import com.squareup.moshi.kotlin.reflect.KotlinJsonAdapterFactory
+import retrofit2.Call
+import retrofit2.Retrofit
+import retrofit2.converter.moshi.MoshiConverterFactory
+import retrofit2.http.GET
+import retrofit2.http.Query
+
+private const val BASE_URL = "https://android-kotlin-fun-mars-server.appspot.com"
+
+private val moshi = Moshi.Builder()
+    .add(KotlinJsonAdapterFactory())
+    .build()
+
+private val retrofit = Retrofit.Builder()
+    .addConverterFactory(MoshiConverterFactory.create(moshi))
+    .baseUrl(BASE_URL)
+    .build()
+
+interface MarsApiService {
+    @GET("/realestate")
+    suspend fun getProperties(@Query("filter") type: String): List<MarsProperty>
+}
+
+object MarsApi {
+    val retrofitService: MarsApiService by lazy {
+        retrofit.create(MarsApiService::class.java)
+    }
+}
+
+enum class MarsApiFilter(val value: String) {
+    SHOW_RENT("rent"),
+    SHOW_BUY("buy"),
+    SHOW_ALL("all")
+}

MarsRealEstate-Starter/app/src/main/java/com/example/android/marsrealestate/network/MarsProperty.kt

@@ -17,4 +17,17 @@
 
 package com.example.android.marsrealestate.network
 
-class MarsProperty()
+import android.os.Parcelable
+import com.squareup.moshi.Json
+import kotlinx.android.parcel.Parcelize
+
+@Parcelize
+data class MarsProperty(
+    val id: String,
+    @Json(name = "img_src") val imgSrcUrl: String,
+    val type: String,
+    val price: Double
+): Parcelable {
+    val isRental
+        get() = type == "rent"
+}

MarsRealEstate-Starter/app/src/main/java/com/example/android/marsrealestate/overview/OverviewFragment.kt

@@ -20,9 +20,13 @@ package com.example.android.marsrealestate.overview
 import android.os.Bundle
 import android.view.*
 import androidx.fragment.app.Fragment
+import androidx.lifecycle.Observer
 import androidx.lifecycle.ViewModelProvider
+import androidx.navigation.fragment.findNavController
 import com.example.android.marsrealestate.R
 import com.example.android.marsrealestate.databinding.FragmentOverviewBinding
+import com.example.android.marsrealestate.databinding.GridViewItemBinding
+import com.example.android.marsrealestate.network.MarsApiFilter
 
 /**
  * This fragment shows the the status of the Mars real-estate web services transaction.
@@ -49,7 +53,17 @@ class OverviewFragment : Fragment() {
 
         // Giving the binding access to the OverviewViewModel
         binding.viewModel = viewModel
+        binding.photosGrid.adapter = PhotoGridAdapter(PhotoGridAdapter.OnClickListener{
+            viewModel.displayPropertyDetails(it)
+        })
 
+        viewModel.navigateToSelectedProperty.observe(this, Observer {
+            if ( null != it ) {
+                this.findNavController().navigate(
+                    OverviewFragmentDirections.actionShowDetail(it))
+                viewModel.displayPropertyDetailsComplete()
+            }
+        })
         setHasOptionsMenu(true)
         return binding.root
     }
@@ -61,4 +75,15 @@ class OverviewFragment : Fragment() {
         inflater.inflate(R.menu.overflow_menu, menu)
         super.onCreateOptionsMenu(menu, inflater)
     }
+
+    override fun onOptionsItemSelected(item: MenuItem?): Boolean {
+        viewModel.updateFilter(
+            when(item?.itemId){
+                R.id.show_rent_menu -> MarsApiFilter.SHOW_RENT
+                R.id.show_buy_menu -> MarsApiFilter.SHOW_BUY
+                else -> MarsApiFilter.SHOW_ALL
+            }
+        )
+        return super.onOptionsItemSelected(item)
+    }
 }

MarsRealEstate-Starter/app/src/main/java/com/example/android/marsrealestate/overview/OverviewViewModel.kt

@@ -20,10 +20,20 @@ package com.example.android.marsrealestate.overview
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import com.example.android.marsrealestate.network.MarsApi
+import com.example.android.marsrealestate.network.MarsApiFilter
+import com.example.android.marsrealestate.network.MarsProperty
+import kotlinx.coroutines.launch
+import retrofit2.Call
+import retrofit2.Response
 
 /**
  * The [ViewModel] that is attached to the [OverviewFragment].
  */
+
+enum class MarsApiStatus { LOADING, ERROR, DONE }
+
 class OverviewViewModel : ViewModel() {
 
     // The internal MutableLiveData String that stores the most recent response
@@ -33,17 +43,55 @@ class OverviewViewModel : ViewModel() {
     val response: LiveData<String>
         get() = _response
 
+    private val _properties = MutableLiveData<List<MarsProperty>>()
+
+    val properties: LiveData<List<MarsProperty>>
+        get() = _properties
+
+    private val _status = MutableLiveData<MarsApiStatus>()
+
+    val status: LiveData<MarsApiStatus>
+        get() = _status
+
+    private val _navigateToSelectedProperty = MutableLiveData<MarsProperty>()
+    val navigateToSelectedProperty: LiveData<MarsProperty>
+        get() = _navigateToSelectedProperty
+
     /**
      * Call getMarsRealEstateProperties() on init so we can display status immediately.
      */
     init {
-        getMarsRealEstateProperties()
+        getMarsRealEstateProperties(MarsApiFilter.SHOW_ALL)
+    }
+
+    fun displayPropertyDetails(marsProperty: MarsProperty){
+        _navigateToSelectedProperty.value = marsProperty
+    }
+
+    fun displayPropertyDetailsComplete(){
+        _navigateToSelectedProperty.value = null
     }
 
     /**
      * Sets the value of the status LiveData to the Mars API status.
      */
-    private fun getMarsRealEstateProperties() {
-        _response.value = "Set the Mars API Response here!"
+    private fun getMarsRealEstateProperties(filter: MarsApiFilter) {
+        viewModelScope.launch {
+            _status.value = MarsApiStatus.LOADING
+            try {
+                val listResult = MarsApi.retrofitService.getProperties(filter.value)
+                if (listResult.isNotEmpty()) {
+                    _properties.value = listResult
+                    _status.value = MarsApiStatus.DONE
+                }
+            } catch (e: Exception) {
+                _status.value = MarsApiStatus.ERROR
+                _properties.value = ArrayList()
+            }
+        }
+    }
+
+    fun updateFilter(filter: MarsApiFilter){
+        getMarsRealEstateProperties(filter)
     }
 }

MarsRealEstate-Starter/app/src/main/java/com/example/android/marsrealestate/overview/PhotoGridAdapter.kt

@@ -17,4 +17,57 @@
 
 package com.example.android.marsrealestate.overview
 
+import android.view.LayoutInflater
+import android.view.ViewGroup
+import androidx.recyclerview.widget.DiffUtil
+import androidx.recyclerview.widget.ListAdapter
+import androidx.recyclerview.widget.RecyclerView
+import com.example.android.marsrealestate.databinding.GridViewItemBinding
+import com.example.android.marsrealestate.network.MarsProperty
 
+class PhotoGridAdapter(private val onClickListener: OnClickListener) : ListAdapter<MarsProperty,
+        PhotoGridAdapter.MarsPropertyViewHolder>(DiffCallback) {
+
+    override fun onCreateViewHolder(
+        parent: ViewGroup,
+        viewType: Int
+    ): MarsPropertyViewHolder {
+        return MarsPropertyViewHolder(
+            GridViewItemBinding.inflate(
+                LayoutInflater.from(parent.context)
+            )
+        )
+    }
+
+    override fun onBindViewHolder(holder: MarsPropertyViewHolder, position: Int) {
+        val marsProperty = getItem(position)
+        holder.itemView.setOnClickListener {
+            onClickListener.onClick(marsProperty)
+        }
+        holder.bind(marsProperty)
+    }
+
+    class MarsPropertyViewHolder(
+        private val binding: GridViewItemBinding
+    ) : RecyclerView.ViewHolder(binding.root) {
+
+        fun bind(marsProperty: MarsProperty) {
+            binding.property = marsProperty
+            binding.executePendingBindings()
+        }
+    }
+
+    companion object DiffCallback : DiffUtil.ItemCallback<MarsProperty>() {
+        override fun areItemsTheSame(oldItem: MarsProperty, newItem: MarsProperty): Boolean {
+            return oldItem === newItem
+        }
+
+        override fun areContentsTheSame(oldItem: MarsProperty, newItem: MarsProperty): Boolean {
+            return oldItem.id == newItem.id
+        }
+    }
+
+    class OnClickListener(val clickListener: (marsProperty: MarsProperty) -> Unit) {
+        fun onClick(marsProperty: MarsProperty) = clickListener(marsProperty)
+    }
+}

MarsRealEstate-Starter/app/src/main/res/layout/fragment_detail.xml

@@ -21,6 +21,13 @@
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools">
 
+    <data>
+
+        <variable
+            name="viewModel"
+            type="com.example.android.marsrealestate.detail.DetailViewModel" />
+    </data>
+
     <ScrollView
         android:layout_width="match_parent"
         android:layout_height="match_parent"
@@ -36,6 +43,7 @@
                 android:layout_width="0dp"
                 android:layout_height="266dp"
                 android:scaleType="centerCrop"
+                app:imageUrl="@{viewModel.selectedProperty.imgSrcUrl}"
                 app:layout_constraintEnd_toEndOf="parent"
                 app:layout_constraintStart_toStartOf="parent"
                 app:layout_constraintTop_toTopOf="parent"
@@ -46,6 +54,7 @@
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:layout_marginTop="16dp"
+                android:text="@{viewModel.displayPropertyType}"
                 android:textColor="#de000000"
                 android:textSize="39sp"
                 app:layout_constraintStart_toStartOf="parent"
@@ -57,6 +66,7 @@
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:layout_marginTop="8dp"
+                android:text="@{viewModel.displayPropertyPrice}"
                 android:textColor="#de000000"
                 android:textSize="20sp"
                 app:layout_constraintStart_toStartOf="parent"

MarsRealEstate-Starter/app/src/main/res/layout/fragment_overview.xml

@@ -31,14 +31,21 @@
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         tools:context="com.example.android.marsrealestate.MainActivity">
-        <TextView
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:text="@{viewModel.response}"
+
+        <androidx.recyclerview.widget.RecyclerView
+            android:id="@+id/photos_grid"
+            app:layoutManager="androidx.recyclerview.widget.GridLayoutManager"
+            android:padding="6dp"
+            app:listData="@{viewModel.properties}"
+            android:clipToPadding="false"
+            app:layout_constraintTop_toTopOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintBottom_toBottomOf="parent"
-            app:layout_constraintLeft_toLeftOf="parent"
-            app:layout_constraintRight_toRightOf="parent"
-            app:layout_constraintTop_toTopOf="parent" />
+            app:spanCount="2"
+            tools:itemCount="16"
+            android:layout_width="0dp"
+            android:layout_height="0dp"/>
 
     </androidx.constraintlayout.widget.ConstraintLayout>
 </layout>

MarsRealEstate-Starter/app/src/main/res/layout/grid_view_item.xml

@@ -1,31 +1,41 @@
 <?xml version="1.0" encoding="utf-8"?>
-
-<!--
-  ~ Copyright 2019, The Android Open Source Project
-  ~
-  ~ Licensed under the Apache License, Version 2.0 (the "License");
-  ~ you may not use this file except in compliance with the License.
-  ~ You may obtain a copy of the License at
-  ~
-  ~     http://www.apache.org/licenses/LICENSE-2.0
-  ~
-  ~ Unless required by applicable law or agreed to in writing, software
-  ~ distributed under the License is distributed on an "AS IS" BASIS,
-  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-  ~ See the License for the specific language governing permissions and
-  ~ limitations under the License.
-  ~
-  -->
-
 <layout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools">
-    <ImageView
-        android:id="@+id/mars_image"
+
+    <data>
+        <import type="android.view.View" />
+
+        <variable
+            name="property"
+            type="com.example.android.marsrealestate.network.MarsProperty" />
+    </data>
+
+    <FrameLayout
         android:layout_width="match_parent"
-        android:layout_height="170dp"
-        android:scaleType="centerCrop"
-        android:adjustViewBounds="true"
-        android:padding="2dp"
-        tools:src="@tools:sample/backgrounds/scenic"/>
-</layout>
+        android:layout_height="match_parent">
+
+        <ImageView
+            android:id="@+id/mars_image"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:adjustViewBounds="true"
+            android:padding="2dp"
+            android:scaleType="centerCrop"
+            app:imageUrl="@{property.imgSrcUrl}" />
+
+        <ImageView
+            android:id="@+id/mars_property_type"
+            android:layout_width="wrap_content"
+            android:layout_height="45dp"
+            android:layout_gravity="bottom|end"
+            android:adjustViewBounds="true"
+            android:padding="5dp"
+            android:visibility="@{property.rental ? View.GONE : View.VISIBLE}"
+            android:scaleType="fitCenter"
+            android:src="@drawable/ic_for_sale_outline"
+            tools:src="@drawable/ic_for_sale_outline" />
+
+    </FrameLayout>
+
+</layout>

MarsRealEstate-Starter/app/src/main/res/navigation/nav_graph.xml

@@ -38,6 +38,10 @@
         android:name="com.example.android.marsrealestate.detail.DetailFragment"
         android:label="fragment_detail"
         tools:layout="@layout/fragment_detail">
+        <argument
+            android:name="selectedProperty"
+            app:argType="com.example.android.marsrealestate.network.MarsProperty"
+            />
     </fragment>
 
 </navigation>

TrackMySleepQuality-Starter/app/build.gradle

@@ -80,5 +80,10 @@ dependencies {
     testImplementation 'junit:junit:4.12'
     androidTestImplementation 'androidx.test.ext:junit:1.1.0'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
+
+    implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:2.2.0"
+
+    // Kotlin Extensions and Coroutines support for Room
+    implementation "androidx.room:room-ktx:$room_version"
 }
 

TrackMySleepQuality-Starter/app/src/androidTest/java/com/example/android/trackmysleepquality/SleepDatabaseTest.kt

@@ -15,57 +15,57 @@
  */
 
 package com.example.android.trackmysleepquality
-//
-//import androidx.room.Room
-//import androidx.test.ext.junit.runners.AndroidJUnit4
-//import androidx.test.platform.app.InstrumentationRegistry
-//import com.example.android.trackmysleepquality.database.SleepDatabase
-//import com.example.android.trackmysleepquality.database.SleepDatabaseDao
-//import com.example.android.trackmysleepquality.database.SleepNight
-//import org.junit.Assert.assertEquals
-//import org.junit.After
-//import org.junit.Before
-//import org.junit.Test
-//import org.junit.runner.RunWith
-//import java.io.IOException
-//
-//
-///**
-// * This is not meant to be a full set of tests. For simplicity, most of your samples do not
-// * include tests. However, when building the Room, it is helpful to make sure it works before
-// * adding the UI.
-// */
-//
-//@RunWith(AndroidJUnit4::class)
-//class SleepDatabaseTest {
-//
-//    private lateinit var sleepDao: SleepDatabaseDao
-//    private lateinit var db: SleepDatabase
-//
-//    @Before
-//    fun createDb() {
-//        val context = InstrumentationRegistry.getInstrumentation().targetContext
-//        // Using an in-memory database because the information stored here disappears when the
-//        // process is killed.
-//        db = Room.inMemoryDatabaseBuilder(context, SleepDatabase::class.java)
-//                // Allowing main thread queries, just for testing.
-//                .allowMainThreadQueries()
-//                .build()
-//        sleepDao = db.sleepDatabaseDao
-//    }
-//
-//    @After
-//    @Throws(IOException::class)
-//    fun closeDb() {
-//        db.close()
-//    }
-//
-//    @Test
-//    @Throws(Exception::class)
-//    fun insertAndGetNight() {
-//        val night = SleepNight()
-//        sleepDao.insert(night)
-//        val tonight = sleepDao.getTonight()
-//        assertEquals(tonight?.sleepQuality, -1)
-//    }
-//}
+
+import androidx.room.Room
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.platform.app.InstrumentationRegistry
+import com.example.android.trackmysleepquality.database.SleepDatabase
+import com.example.android.trackmysleepquality.database.SleepDatabaseDao
+import com.example.android.trackmysleepquality.database.SleepNight
+import org.junit.Assert.assertEquals
+import org.junit.After
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import java.io.IOException
+
+
+/**
+ * This is not meant to be a full set of tests. For simplicity, most of your samples do not
+ * include tests. However, when building the Room, it is helpful to make sure it works before
+ * adding the UI.
+ */
+
+@RunWith(AndroidJUnit4::class)
+class SleepDatabaseTest {
+
+    private lateinit var sleepDao: SleepDatabaseDao
+    private lateinit var db: SleepDatabase
+
+    @Before
+    fun createDb() {
+        val context = InstrumentationRegistry.getInstrumentation().targetContext
+        // Using an in-memory database because the information stored here disappears when the
+        // process is killed.
+        db = Room.inMemoryDatabaseBuilder(context, SleepDatabase::class.java)
+                // Allowing main thread queries, just for testing.
+                .allowMainThreadQueries()
+                .build()
+        sleepDao = db.sleepDatabaseDao
+    }
+
+    @After
+    @Throws(IOException::class)
+    fun closeDb() {
+        db.close()
+    }
+
+    @Test
+    @Throws(Exception::class)
+    fun insertAndGetNight() {
+        val night = SleepNight()
+        sleepDao.insert(night)
+        val tonight = sleepDao.getTonight()
+        assertEquals(tonight?.sleepQuality, -1)
+    }
+}

TrackMySleepQuality-Starter/app/src/main/java/com/example/android/trackmysleepquality/database/SleepDatabase.kt

@@ -15,3 +15,37 @@
  */
 
 package com.example.android.trackmysleepquality.database
+
+import android.content.Context
+import androidx.room.Database
+import androidx.room.Room
+import androidx.room.RoomDatabase
+
+@Database(entities = [SleepNight::class], version = 1, exportSchema = false)
+abstract class SleepDatabase : RoomDatabase() {
+    abstract val sleepDatabaseDao: SleepDatabaseDao
+
+    companion object {
+        @Volatile
+        private var INSTANCE: SleepDatabase? = null
+
+        fun getInstance(context: Context): SleepDatabase {
+            synchronized(this) {
+                var instance = INSTANCE
+
+                if (instance == null) {
+                    instance = Room.databaseBuilder(
+                        context.applicationContext,
+                        SleepDatabase::class.java,
+                        "sleep_history_database"
+                    )
+                        .fallbackToDestructiveMigration()
+                        .allowMainThreadQueries()
+                        .build()
+                    INSTANCE = instance
+                }
+                return instance
+            }
+        }
+    }
+}

TrackMySleepQuality-Starter/app/src/main/java/com/example/android/trackmysleepquality/database/SleepDatabaseDao.kt

@@ -16,7 +16,29 @@
 
 package com.example.android.trackmysleepquality.database
 
+import androidx.lifecycle.LiveData
 import androidx.room.Dao
+import androidx.room.Insert
+import androidx.room.Query
+import androidx.room.Update
 
 @Dao
-interface SleepDatabaseDao
+interface SleepDatabaseDao {
+    @Insert
+    fun insert(night: SleepNight)
+
+    @Update
+    fun update(night: SleepNight)
+
+    @Query("SELECT * from daily_sleep_quality_table WHERE nightId = :key")
+    fun get(key: Long): SleepNight?
+
+    @Query("DELETE FROM daily_sleep_quality_table")
+    fun clear()
+
+    @Query("SELECT * FROM daily_sleep_quality_table ORDER BY nightId DESC LIMIT 1")
+    fun getTonight(): SleepNight?
+
+    @Query("SELECT * FROM daily_sleep_quality_table ORDER BY nightId DESC")
+    fun getAllNights(): LiveData<List<SleepNight>>
+}

TrackMySleepQuality-Starter/app/src/main/java/com/example/android/trackmysleepquality/database/SleepNight.kt

@@ -16,3 +16,18 @@
 
 package com.example.android.trackmysleepquality.database
 
+import androidx.room.ColumnInfo
+import androidx.room.Entity
+import androidx.room.PrimaryKey
+
+@Entity(tableName = "daily_sleep_quality_table")
+data class SleepNight(
+    @PrimaryKey(autoGenerate = true)
+    var nightId: Long = 0L,
+    @ColumnInfo(name = "start_time_milli")
+    val startTimeMilli: Long = System.currentTimeMillis(),
+    @ColumnInfo(name = "end_time_milli")
+    var endTimeMilli: Long = startTimeMilli,
+    @ColumnInfo(name = "quality_rating")
+    var sleepQuality: Int = -1
+)

TrackMySleepQuality-Starter/app/src/main/java/com/example/android/trackmysleepquality/sleepquality/SleepQualityViewModel.kt

@@ -15,3 +15,8 @@
  */
 
 package com.example.android.trackmysleepquality.sleepquality
+
+import androidx.lifecycle.ViewModel
+
+class SleepQualityViewModel : ViewModel() {
+}

TrackMySleepQuality-Starter/app/src/main/java/com/example/android/trackmysleepquality/sleepquality/SleepQualityViewModelFactory.kt

@@ -15,3 +15,16 @@
  */
 
 package com.example.android.trackmysleepquality.sleepquality
+
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.ViewModelProvider
+
+class SleepQualityViewModelFactory : ViewModelProvider.Factory {
+
+    override fun <T : ViewModel?> create(modelClass: Class<T>): T {
+        if (modelClass.isAssignableFrom(SleepQualityViewModel::class.java)) {
+            return SleepQualityViewModel() as T
+        }
+        throw IllegalArgumentException("Unknown viewModel class")
+    }
+}

TrackMySleepQuality-Starter/app/src/main/java/com/example/android/trackmysleepquality/sleeptracker/SleepTrackerFragment.kt

@@ -22,7 +22,9 @@ import android.view.View
 import android.view.ViewGroup
 import androidx.databinding.DataBindingUtil
 import androidx.fragment.app.Fragment
+import androidx.lifecycle.ViewModelProvider
 import com.example.android.trackmysleepquality.R
+import com.example.android.trackmysleepquality.database.SleepDatabase
 import com.example.android.trackmysleepquality.databinding.FragmentSleepTrackerBinding
 
 /**
@@ -37,12 +39,29 @@ class SleepTrackerFragment : Fragment() {
      *
      * This function uses DataBindingUtil to inflate R.layout.fragment_sleep_quality.
      */
-    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
-                              savedInstanceState: Bundle?): View? {
+    override fun onCreateView(
+        inflater: LayoutInflater, container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
 
         // Get a reference to the binding object and inflate the fragment views.
         val binding: FragmentSleepTrackerBinding = DataBindingUtil.inflate(
-                inflater, R.layout.fragment_sleep_tracker, container, false)
+            inflater, R.layout.fragment_sleep_tracker, container, false
+        )
+
+        val application = requireNotNull(this.activity).application
+
+        val dataSource = SleepDatabase.getInstance(application).sleepDatabaseDao
+
+        val viewModelFactory = SleepTrackerViewModelFactory(dataSource, application)
+
+        val sleepTrackerViewModel =
+            ViewModelProvider(
+                this, viewModelFactory
+            ).get(SleepTrackerViewModel::class.java)
+
+        binding.lifecycleOwner = this
+        binding.sleepTrackerViewModel = sleepTrackerViewModel
 
         return binding.root
     }

TrackMySleepQuality-Starter/app/src/main/java/com/example/android/trackmysleepquality/sleeptracker/SleepTrackerViewModel.kt

@@ -18,13 +18,80 @@ package com.example.android.trackmysleepquality.sleeptracker
 
 import android.app.Application
 import androidx.lifecycle.AndroidViewModel
+import androidx.lifecycle.MutableLiveData
+import androidx.lifecycle.Transformations
+import androidx.lifecycle.viewModelScope
 import com.example.android.trackmysleepquality.database.SleepDatabaseDao
+import com.example.android.trackmysleepquality.database.SleepNight
+import kotlinx.coroutines.launch
 
 /**
  * ViewModel for SleepTrackerFragment.
  */
 class SleepTrackerViewModel(
-        val database: SleepDatabaseDao,
-        application: Application) : AndroidViewModel(application) {
+    val database: SleepDatabaseDao,
+    application: Application
+) : AndroidViewModel(application) {
+
+    private val nights = database.getAllNights()
+
+    val nightsString = Transformations.map(nights) { nights ->
+        "${nights.toString()}"//        formatNights(nights, application.resources)
+    }
+
+    private var tonight = MutableLiveData<SleepNight?>()
+
+    init {
+        initializeTonight()
+    }
+
+    private fun initializeTonight() {
+        viewModelScope.launch {
+//            tonight.value = getTonightFromDatabase()
+        }
+    }
+
+    private suspend fun getTonightFromDatabase(): SleepNight? {
+        var night: SleepNight? = database.getTonight() ?: return null
+        if (night?.endTimeMilli != night?.startTimeMilli) {
+            night = null
+        }
+        return night
+    }
+
+    fun onStartTracking() {
+        viewModelScope.launch {
+            val newNight = SleepNight()
+            insert(newNight)
+            tonight.value = getTonightFromDatabase()
+        }
+    }
+
+    private suspend fun insert(night: SleepNight) {
+        database.insert(night)
+    }
+
+    fun onStopTracking() {
+        viewModelScope.launch {
+            val oldNight = tonight.value ?: return@launch
+            oldNight.endTimeMilli = System.currentTimeMillis()
+            update(oldNight)
+        }
+    }
+
+    private suspend fun update(night: SleepNight) {
+        database.update(night)
+    }
+
+    fun onClear() {
+        viewModelScope.launch {
+            clear()
+            tonight.value = null
+        }
+    }
+
+    suspend fun clear() {
+        database.clear()
+    }
 }
 

TrackMySleepQuality-Starter/app/src/main/res/layout/fragment_sleep_tracker.xml

@@ -24,6 +24,9 @@
          click handlers, and state variables. -->
     <data>
 
+        <variable
+            name="sleepTrackerViewModel"
+            type="com.example.android.trackmysleepquality.sleeptracker.SleepTrackerViewModel" />
     </data>
 
     <!-- Start of the visible fragment layout using ConstraintLayout -->
@@ -49,14 +52,30 @@
                  which keeps it displayed and updated in the TextView
                  whenever it changes. -->
 
-            <TextView
-                android:id="@+id/textview"
-                android:layout_width="match_parent"
+            <androidx.appcompat.widget.LinearLayoutCompat
+                android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
-                android:layout_marginStart="@dimen/margin"
-                android:layout_marginTop="@dimen/margin"
-                android:layout_marginEnd="@dimen/margin"
-                android:text="@string/how_was_hour_sleep" />
+                android:orientation="vertical">
+
+                <TextView
+                    android:id="@+id/textview"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:layout_marginStart="@dimen/margin"
+                    android:layout_marginTop="@dimen/margin"
+                    android:layout_marginEnd="@dimen/margin"
+                    android:text="@string/how_was_hour_sleep" />
+
+                <TextView
+                    android:id="@+id/format_Nights"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:layout_marginStart="@dimen/margin"
+                    android:layout_marginTop="@dimen/margin"
+                    android:layout_marginEnd="@dimen/margin"
+                    android:text="@{sleepTrackerViewModel.nightsString}" />
+
+            </androidx.appcompat.widget.LinearLayoutCompat>
         </ScrollView>
 
         <!-- With data binding and LiveData, we can track the buttons' visibility states
@@ -69,6 +88,7 @@
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:layout_marginStart="@dimen/margin"
+            android:onClick="@{()->sleepTrackerViewModel.onStartTracking()}"
             android:text="@string/start"
             app:layout_constraintBaseline_toBaselineOf="@id/stop_button"
             app:layout_constraintEnd_toStartOf="@+id/stop_button"
@@ -82,6 +102,7 @@
             android:layout_height="wrap_content"
             android:layout_marginTop="@dimen/margin"
             android:layout_marginEnd="@dimen/margin"
+            android:onClick="@{() -> sleepTrackerViewModel.onStopTracking()}"
             android:text="@string/stop"
             app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintStart_toEndOf="@+id/start_button"
@@ -95,10 +116,12 @@
             android:layout_marginStart="@dimen/margin"
             android:layout_marginEnd="@dimen/margin"
             android:layout_marginBottom="@dimen/margin"
+            android:onClick="@{() -> sleepTrackerViewModel.onClear()}"
             android:text="@string/clear"
             app:layout_constraintBottom_toBottomOf="parent"
             app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintStart_toStartOf="parent" />
 
     </androidx.constraintlayout.widget.ConstraintLayout>
+
 </layout>