Milestone6

README.md

@@ -1,9 +1,57 @@
 # Yuki's Android Learning Plan guided by Sammy #
 ## Milestones
-1. Bare bones application, including main components and architecture. 
+1. Bare bones application, including main components and architecture.
 * Appropriate choice of architecture.
-* Defining components that are needed and how they fit into the architecture. 
-2. API integration  
-* Implementation of network layer 
-3. Displaying list of meteors 
-* Using appropriate Android components, display a list of meteors received from the API (point 2). 
+* Defining components that are needed and how they fit into the architecture.
+2. API integration
+* Implementation of network layer
+3. Displaying list of meteors
+* Using appropriate Android components, display a list of meteors received from the API (point 2).
+4. List filtering and sorting
+* Add interactive filter & sorting UI components to the view 
+* Display filtered/sorted list
+5. Detail view 
+* More complex view logic by adding a detail view and handling navigation 
+6. Persistence
+* List of meteors should be stored for offline usage.
+* Update application logic to use offline state store whenever API is not available. 
+
+## Comments Summary
+1. ListAdapter vs. RecyclerViewAdapter -> RecyclerViewAdapter
+2. Lifecycle-Aware Components -> lifecycle
+```MainActivity.kt
+override fun onCreate(savedInstanceState: Bundle?) {
+    lifecycle.addObserver(viewModel)
+}
+```
+```MainViewModel.kt
+private val repository: MeteorRepository) : ViewModel(), DefaultLifecycleObserver {
+    override fun onResume(owner: LifecycleOwner) {
+        getMeteorsInfo()
+    }
+}
+```
+
+3. Prevent leak -> onDestroy()
+```MainActivity
+override fun onDestroy() {
+   super.onDestroy()
+   Injection.destroy()
+   lifecycle.removeObserver(viewModel)}
+```
+"This is a code vulnerability. You're setting the entire Activity as the listener, which means that the Activity can't be garbage collected as long as there is a reference to it. When is the reference to the activity cleaned up? Furthermore, the Activity doesn't really need to be informed of clicks when the activity is no longer in view. So: it's a good practise to "unset" the listener, for example in 'onDestroy()'."
+
+4. RelativeLayout vs. LinearLayout -> RelativeLayout
+
+5. Don't use hardcoded strings, use string resources instead. -> R.string.name
+
+6. MVVM architecture (especially the functionality of ViewModel)
+
+7. val vs. var -> val 
+
+8. unnecessary init{} -> declaration with initialization 
+“Declare context and recyclerItemClickListener as private vals in the MeteorsListAdapter initialisor, and you can use them as variables in the class. ”
+
+9. MutableList vs. List -> List<MeteorData>
+
+10. databinding

app/build.gradle

@@ -41,23 +41,35 @@ android {
         }
     }
     buildFeatures {
-        viewBinding true
+        dataBinding true
     }
 }
 
 dependencies {
-    implementation 'com.google.code.gson:gson:2.8.5'
+
     implementation 'androidx.core:core-ktx:1.7.0'
+    implementation 'androidx.lifecycle:lifecycle-extensions:2.2.0'
     implementation 'androidx.appcompat:appcompat:1.5.1'
+    implementation "androidx.lifecycle:lifecycle-livedata-ktx:2.5.1"
     implementation 'com.google.android.material:material:1.7.0'
     implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
-    implementation 'androidx.navigation:navigation-fragment-ktx:2.5.2'
-    implementation 'androidx.navigation:navigation-ui-ktx:2.5.2'
-    implementation 'androidx.swiperefreshlayout:swiperefreshlayout:1.0.0'
-    implementation 'com.google.android.gms:play-services-basement:17.3.0'
-    implementation 'com.google.android.gms:play-services-maps:17.0.0'
+    implementation 'androidx.swiperefreshlayout:swiperefreshlayout:1.1.0'
+    implementation 'androidx.fragment:fragment-ktx:1.5.5'
+
+    implementation 'com.google.code.gson:gson:2.8.9'
+    implementation 'com.google.android.gms:play-services-basement:18.1.0'
+    implementation 'com.google.android.gms:play-services-maps:18.1.0'
+
+    implementation 'com.squareup.retrofit2:converter-moshi:2.9.0'
+    implementation 'com.squareup.retrofit2:converter-gson:2.4.0'
+    implementation 'com.squareup.okhttp3:okhttp:4.10.0'
+    implementation "com.squareup.okhttp3:logging-interceptor:4.10.0"
+
+    implementation 'com.orhanobut:hawk:2.0.1'
+
+    implementation "io.coil-kt:coil:2.2.2"
+
     testImplementation 'junit:junit:4.13.2'
     androidTestImplementation 'androidx.test.ext:junit:1.1.3'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'
-
 }

app/src/main/AndroidManifest.xml

@@ -17,7 +17,7 @@
             android:name="com.google.android.geo.API_KEY"
             android:value="AIzaSyBBuSbrTz9SuyFwci1bCzyO0ZLPspoP2os"/>
 
-        <activity android:name=".ui.MainActivity"
+        <activity android:name=".view.MainActivity"
             android:exported="true">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
@@ -26,7 +26,7 @@
             </intent-filter>
         </activity>
         <activity
-            android:name=".ui.MapActivity"
+            android:name=".view.MapActivity"
             android:screenOrientation="portrait">
         </activity>
     </application>

app/src/main/java/com/example/assignment/adapter/MeteorsListAdapter.kt

@@ -9,27 +9,16 @@ import androidx.recyclerview.widget.RecyclerView
 import com.example.assignment.R
 import com.example.assignment.databinding.ItemMeteoriteBinding
 import com.example.assignment.model.MeteorData
-import com.google.gson.Gson
-import java.io.IOException
-import java.io.InputStream
-
+import com.orhanobut.hawk.Hawk.init
 
 class MeteorsListAdapter(
-    context: Context,
-    recyclerItemClickListener: RecyclerItemClickListener
+    meteorList: List<MeteorData>,
+    var context: Context,
+    var recyclerItemClickListener: RecyclerItemClickListener
 ) : RecyclerView.Adapter<MeteorsListAdapter.MeteorsViewHolder>() {
 
     private val TAG: String = this.javaClass.name
-    var meteorDataList: MutableList<MeteorData>
-    var context: Context
-    var recyclerItemClickListener: RecyclerItemClickListener
-
-    init {
-        this.context = context
-        meteorDataList = parseJsonToObject(context) as MutableList<MeteorData>
-        Log.d(TAG, meteorDataList.toString())
-        this.recyclerItemClickListener = recyclerItemClickListener
-    }
+    var meteorDataList: List<MeteorData> = meteorList
 
     override fun onCreateViewHolder(
         parent: ViewGroup,
@@ -54,28 +43,17 @@ class MeteorsListAdapter(
         return meteorDataList.size
     }
 
-    private fun remove(item: MeteorData) {
-        Log.d(TAG, "remove list item:$item")
-        val pos = meteorDataList.indexOf(item)
-        if (pos > -1) {
-            meteorDataList.removeAt(pos)
-            notifyItemRemoved(pos)
-        }
+    fun update(data: List<MeteorData>) {
+        meteorDataList = data
+        notifyDataSetChanged()
     }
 
     private fun getItem(position: Int): MeteorData {
         return meteorDataList[position]
     }
 
-    fun clear() {
-        Log.d(TAG, "clear Recycler view.")
-        while (itemCount > 0) {
-            remove(getItem(0))
-        }
-    }
-
     interface RecyclerItemClickListener {
-        fun onRecyclerItemClick(meteorItem: MeteorData?)
+        fun onRecyclerItemClick(meteorItem: MeteorData)
     }
 
     inner class MeteorsViewHolder(itemBinding: ItemMeteoriteBinding) :
@@ -97,28 +75,4 @@ class MeteorsListAdapter(
             })
         }
     }
-
-    private fun loadJSONFromAsset(context: Context): String? {
-        var json: String? = null
-        json = try {
-            val `is`: InputStream = context.assets.open("y77d-th95.json")
-            val size: Int = `is`.available()
-            val buffer = ByteArray(size)
-            `is`.read(buffer)
-            `is`.close()
-            String(buffer)
-        } catch (ex: IOException) {
-            ex.printStackTrace()
-            return null
-        }
-        return json
-    }
-
-    private fun parseJsonToObject(context: Context): List<MeteorData> {
-        val jsonString: String? = loadJSONFromAsset(context)
-        return Gson().fromJson(jsonString, Array<MeteorData>::class.java).toList()
-    }
-
-
-
 }

app/src/main/java/com/example/assignment/data/ApiClient.kt

@@ -0,0 +1,44 @@
+package com.example.assignment.data
+
+import com.example.assignment.model.MeteorData
+import okhttp3.OkHttpClient
+import okhttp3.logging.HttpLoggingInterceptor
+import retrofit2.Call
+import retrofit2.Retrofit
+import retrofit2.converter.gson.GsonConverterFactory
+import retrofit2.http.GET
+
+
+object ApiClient {
+
+    private const val API_BASE_URL = "https://data.nasa.gov/"
+
+    private var servicesApiInterface: MeteorApiInterface? = null
+
+    fun build(): MeteorApiInterface {
+        val builder: Retrofit.Builder = Retrofit.Builder()
+            .baseUrl(API_BASE_URL)
+            .addConverterFactory(GsonConverterFactory.create())
+
+        val httpClient: OkHttpClient.Builder = OkHttpClient.Builder()
+        httpClient.addInterceptor(interceptor())
+
+        val retrofit: Retrofit = builder.client(httpClient.build()).build()
+        servicesApiInterface = retrofit.create(
+            MeteorApiInterface::class.java
+        )
+
+        return servicesApiInterface as MeteorApiInterface
+    }
+
+    private fun interceptor(): HttpLoggingInterceptor {
+        val httpLoggingInterceptor = HttpLoggingInterceptor()
+        httpLoggingInterceptor.level = HttpLoggingInterceptor.Level.BODY
+        return httpLoggingInterceptor
+    }
+
+    interface MeteorApiInterface {
+        @GET("resource/y77d-th95.json?\$where=year>='1900-01-01T00:00:00.000'")//&\$limit=15")
+        fun getMeteorsJsonData(): Call<List<MeteorData>>
+    }
+}

app/src/main/java/com/example/assignment/data/MeteorRemoteDataSource.kt

@@ -0,0 +1,42 @@
+package com.example.assignment.data
+
+import com.example.assignment.model.MeteorData
+import com.example.assignment.model.MeteorDataSource
+import retrofit2.Call
+import retrofit2.Callback
+import retrofit2.Response
+
+
+class MeteorRemoteDataSource(apiClient: ApiClient) : MeteorDataSource {
+
+    private var call: Call<List<MeteorData>>? = null
+    private val service = apiClient.build()
+
+    override fun retrieveMeteor(callback: OperationCallback<MeteorData>) {
+        call = service.getMeteorsJsonData()
+        call?.enqueue(object : Callback<List<MeteorData>> {
+            override fun onFailure(call: Call<List<MeteorData>>, t: Throwable) {
+                callback.onError(t.message)
+            }
+
+            override fun onResponse(
+                call: Call<List<MeteorData>>,
+                response: Response<List<MeteorData>>
+            ) {
+                response.body()?.let {
+                    if (response.isSuccessful) {
+                        callback.onSuccess(it)
+                    } else {
+                        callback.onError("Error")
+                    }
+                }
+            }
+        })
+    }
+
+    override fun cancel() {
+        call?.let {
+            it.cancel()
+        }
+    }
+}

app/src/main/java/com/example/assignment/data/OperationCallback.kt

@@ -0,0 +1,7 @@
+package com.example.assignment.data
+
+
+interface OperationCallback<T> {
+    fun onSuccess(data: List<T>?)
+    fun onError(error: String?)
+}

app/src/main/java/com/example/assignment/di/injection.kt

@@ -0,0 +1,44 @@
+package com.example.assignment.di
+
+import android.content.Context
+import com.example.assignment.data.ApiClient
+import com.example.assignment.data.MeteorRemoteDataSource
+import com.example.assignment.model.MeteorDataSource
+import com.example.assignment.model.MeteorRepository
+import com.example.assignment.viewModel.ViewModelFactory
+
+object Injection {
+
+    private var meteorDataSource: MeteorDataSource? = null
+    private var meteorRepository: MeteorRepository? = null
+    private var meteorViewModelFactory: ViewModelFactory? = null
+
+    private fun createMeteorDataSource(): MeteorDataSource {
+        val dataSource = MeteorRemoteDataSource(ApiClient)
+        meteorDataSource = dataSource
+        return dataSource
+    }
+
+    private fun createMeteorRepository(): MeteorRepository {
+        val repository = MeteorRepository(provideDataSource())
+        meteorRepository = repository
+        return repository
+    }
+
+    private fun createFactory(): ViewModelFactory {
+        val factory = ViewModelFactory(providerRepository())
+        meteorViewModelFactory = factory
+        return factory
+    }
+
+    private fun provideDataSource() = meteorDataSource ?: createMeteorDataSource()
+    private fun providerRepository() = meteorRepository ?: createMeteorRepository()
+
+    fun provideViewModelFactory() = meteorViewModelFactory ?: createFactory()
+
+    fun destroy() {
+        meteorDataSource = null
+        meteorRepository = null
+        meteorViewModelFactory = null
+    }
+}