feat: Add speakers under session (#1788)

Detail:
- Set up recycler/adapter to fetch speakers under session

Fixes: #1786

Author: anhanh11001

app/src/main/java/org/fossasia/openevent/general/di/Modules.kt

@@ -203,7 +203,7 @@ val viewModelModule = module {
     viewModel { ProfileViewModel(get(), get()) }
     viewModel { SignUpViewModel(get(), get(), get()) }
     viewModel { EventDetailsViewModel(get(), get(), get(), get(), get(), get(), get(), get()) }
-    viewModel { SessionViewModel(get(), get()) }
+    viewModel { SessionViewModel(get(), get(), get()) }
     viewModel { SearchViewModel(get(), get(), get(), get()) }
     viewModel { AttendeeViewModel(get(), get(), get(), get(), get(), get(), get()) }
     viewModel { SearchLocationViewModel(get(), get()) }

app/src/main/java/org/fossasia/openevent/general/event/EventDetailsFragment.kt

@@ -80,9 +80,6 @@ import org.fossasia.openevent.general.utils.Utils.setToolbar
 import org.jetbrains.anko.design.longSnackbar
 import org.jetbrains.anko.design.snackbar
 
-const val EVENT_ID = "eventId"
-const val EVENT_TOPIC_ID = "eventTopicId"
-const val EVENT_LOCATION = "eventLocation"
 const val EVENT_DETAIL_FRAGMENT = "eventDetailFragment;"
 
 class EventDetailsFragment : Fragment() {

app/src/main/java/org/fossasia/openevent/general/sessions/SessionFragment.kt

@@ -13,6 +13,9 @@ import androidx.fragment.app.Fragment
 import androidx.lifecycle.Observer
 import androidx.navigation.fragment.navArgs
 import com.squareup.picasso.Picasso
+import androidx.navigation.Navigation.findNavController
+import androidx.recyclerview.widget.LinearLayoutManager
+import androidx.recyclerview.widget.LinearLayoutManager.HORIZONTAL
 import kotlinx.android.synthetic.main.fragment_session.view.progressBar
 import kotlinx.android.synthetic.main.fragment_session.view.sessionDetailTrack
 import kotlinx.android.synthetic.main.fragment_session.view.sessionDetailAbstract
@@ -34,7 +37,12 @@ import kotlinx.android.synthetic.main.fragment_session.view.sessionDetailAbstrac
 import kotlinx.android.synthetic.main.fragment_session.view.sessionDetailTrackContainer
 import kotlinx.android.synthetic.main.fragment_session.view.sessionDetailSignUpButton
 import kotlinx.android.synthetic.main.fragment_session.view.sessionDetailTrackIcon
+import kotlinx.android.synthetic.main.fragment_session.view.speakersUnderSessionRecycler
+import kotlinx.android.synthetic.main.fragment_session.view.speakersProgressBar
+import kotlinx.android.synthetic.main.fragment_session.view.sessionDetailSpeakersContainer
 import org.fossasia.openevent.general.R
+import org.fossasia.openevent.general.common.SpeakerClickListener
+import org.fossasia.openevent.general.speakers.SpeakerRecyclerAdapter
 import org.fossasia.openevent.general.event.EventUtils
 import org.fossasia.openevent.general.utils.Utils
 import org.fossasia.openevent.general.utils.Utils.setToolbar
@@ -47,6 +55,7 @@ const val LINE_COUNT_ABSTRACT = 3
 class SessionFragment : Fragment() {
     private lateinit var rootView: View
     private val sessionViewModel by viewModel<SessionViewModel>()
+    private val speakersAdapter = SpeakerRecyclerAdapter()
     private val safeArgs: SessionFragmentArgs by navArgs()
 
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
@@ -59,6 +68,9 @@ class SessionFragment : Fragment() {
             .nonNull()
             .observe(viewLifecycleOwner, Observer {
                 rootView.snackbar(it)
+                if (it == getString(R.string.error_fetching_speakers_for_session)) {
+                    rootView.sessionDetailSpeakersContainer.visibility = View.GONE
+                }
             })
 
         sessionViewModel.session
@@ -74,11 +86,48 @@ class SessionFragment : Fragment() {
                 rootView.sessionDetailContainer.visibility = if (it) View.GONE else View.VISIBLE
             })
 
+        sessionViewModel.speakersUnderSession
+            .nonNull()
+            .observe(viewLifecycleOwner, Observer {
+                speakersAdapter.addAll(it)
+                if (it.isEmpty())
+                    rootView.sessionDetailSpeakersContainer.visibility = View.GONE
+                else
+                    rootView.speakersProgressBar.visibility = View.GONE
+            })
+
         sessionViewModel.loadSession(safeArgs.sessionId)
+        val currentSpeakers = sessionViewModel.speakersUnderSession.value
+        if (currentSpeakers == null)
+            sessionViewModel.loadSpeakersUnderSession(safeArgs.sessionId)
+        else {
+            speakersAdapter.addAll(currentSpeakers)
+            if (currentSpeakers.isEmpty())
+                rootView.sessionDetailSpeakersContainer.visibility = View.GONE
+            else
+                rootView.speakersProgressBar.visibility = View.GONE
+        }
+
+        val layoutManager = LinearLayoutManager(context)
+        layoutManager.orientation = HORIZONTAL
+        rootView.speakersUnderSessionRecycler.layoutManager = layoutManager
+        rootView.speakersUnderSessionRecycler.adapter = speakersAdapter
 
         return rootView
     }
 
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        super.onViewCreated(view, savedInstanceState)
+        val speakerClickListener = object : SpeakerClickListener {
+            override fun onClick(speakerId: Long) {
+                findNavController(rootView).navigate(SessionFragmentDirections.actionSessionToSpeaker(speakerId))
+            }
+        }
+        speakersAdapter.apply {
+            onSpeakerClick = speakerClickListener
+        }
+    }
+
     override fun onOptionsItemSelected(item: MenuItem): Boolean {
         return when (item.itemId) {
             android.R.id.home -> {

app/src/main/java/org/fossasia/openevent/general/sessions/SessionViewModel.kt

@@ -3,17 +3,20 @@ package org.fossasia.openevent.general.sessions
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
-import io.reactivex.android.schedulers.AndroidSchedulers
 import org.fossasia.openevent.general.BuildConfig.MAPBOX_KEY
 import io.reactivex.disposables.CompositeDisposable
-import io.reactivex.schedulers.Schedulers
+import io.reactivex.rxkotlin.plusAssign
 import org.fossasia.openevent.general.R
 import org.fossasia.openevent.general.common.SingleLiveEvent
 import org.fossasia.openevent.general.data.Resource
+import org.fossasia.openevent.general.speakers.Speaker
+import org.fossasia.openevent.general.speakers.SpeakerService
+import org.fossasia.openevent.general.utils.extensions.withDefaultSchedulers
 import timber.log.Timber
 
 class SessionViewModel(
     private val sessionService: SessionService,
+    private val speakerService: SpeakerService,
     private val resource: Resource
 ) : ViewModel() {
     private val compositeDisposable = CompositeDisposable()
@@ -24,16 +27,17 @@ class SessionViewModel(
     val progress: LiveData<Boolean> = mutableProgress
     private val mutableError = SingleLiveEvent<String>()
     val error: LiveData<String> = mutableError
+    private val mutableSpeakers = MutableLiveData<List<Speaker>>()
+    val speakersUnderSession: LiveData<List<Speaker>> = mutableSpeakers
 
     fun loadSession(id: Long) {
         if (id == -1L) {
             mutableError.value = resource.getString(R.string.error_fetching_event_message)
             return
         }
 
-        compositeDisposable.add(sessionService.fetchSession(id)
-            .subscribeOn(Schedulers.io())
-            .observeOn(AndroidSchedulers.mainThread())
+        compositeDisposable += sessionService.fetchSession(id)
+            .withDefaultSchedulers()
             .doOnSubscribe { mutableProgress.value = true }
             .subscribe({
                 mutableSession.value = it
@@ -43,7 +47,22 @@ class SessionViewModel(
                 mutableError.value = resource.getString(R.string.error_fetching_event_section_message,
                     resource.getString(R.string.session))
             })
-        )
+    }
+
+    fun loadSpeakersUnderSession(id: Long) {
+        if (id == -1L) {
+            mutableError.value = resource.getString(R.string.error_fetching_speakers_for_session)
+            return
+        }
+
+        compositeDisposable += speakerService.fetchSpeakerForSession(id)
+            .withDefaultSchedulers()
+            .subscribe({
+                mutableSpeakers.value = it
+            }, {
+                Timber.e(it, "Error fetching speakers for session $id")
+                mutableError.value = resource.getString(R.string.error_fetching_speakers_for_session)
+            })
     }
 
     fun loadMap(latitude: String, longitude: String): String {

app/src/main/java/org/fossasia/openevent/general/speakers/SpeakerApi.kt

@@ -9,6 +9,9 @@ interface SpeakerApi {
     @GET("events/{id}/speakers")
     fun getSpeakerForEvent(@Path("id") id: Long): Single<List<Speaker>>
 
+    @GET("sessions/{sessionId}/speakers")
+    fun getSpeakersForSession(@Path("sessionId") id: Long): Single<List<Speaker>>
+
     @GET("speakers/{speaker_id}")
     fun getSpeakerWithId(@Path("speaker_id") id: Long): Single<Speaker>
 }

app/src/main/java/org/fossasia/openevent/general/speakers/SpeakerService.kt

@@ -24,6 +24,12 @@ class SpeakerService(
         return speakerWithEventDao.getSpeakerWithEventId(id)
     }
 
+    fun fetchSpeakerForSession(sessionId: Long): Single<List<Speaker>> =
+        speakerApi.getSpeakersForSession(sessionId)
+            .doOnSuccess {
+                speakerDao.insertSpeakers(it)
+            }
+
     fun fetchSpeaker(id: Long): Flowable<Speaker> {
         return speakerDao.getSpeaker(id)
     }

app/src/main/res/layout/fragment_session.xml

@@ -220,6 +220,36 @@
             android:background="@color/grey" />
     </LinearLayout>
 
+    <LinearLayout
+        android:id="@+id/sessionDetailSpeakersContainer"
+        android:orientation="vertical"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:animateLayoutChanges="true">
+        <TextView
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:text="@string/speakers"
+            android:textColor="@color/dark_grey"
+            android:textSize="@dimen/event_details_headers"
+            android:layout_marginBottom="@dimen/layout_margin_medium"/>
+        <ProgressBar
+            android:id="@+id/speakersProgressBar"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="center"/>
+        <androidx.recyclerview.widget.RecyclerView
+            android:id="@+id/speakersUnderSessionRecycler"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"/>
+        <View
+            android:layout_width="match_parent"
+            android:layout_height="@dimen/event_details_divider"
+            android:layout_marginTop="@dimen/layout_margin_large"
+            android:layout_marginBottom="@dimen/layout_margin_large"
+            android:background="@color/grey" />
+    </LinearLayout>
+
     <androidx.appcompat.widget.AppCompatButton
         android:id="@+id/sessionDetailSignUpButton"
         android:layout_width="match_parent"

app/src/main/res/navigation/navigation_graph.xml

@@ -251,6 +251,13 @@
         android:name="org.fossasia.openevent.general.sessions.SessionFragment"
         android:label="SessionFragment"
         tools:layout="@layout/fragment_session">
+        <action
+            android:id="@+id/action_session_to_speaker"
+            app:destination="@id/speakerFragment"
+            app:popEnterAnim="@anim/slide_in_left"
+            app:popExitAnim="@anim/slide_out_right"
+            app:enterAnim="@anim/slide_in_right"
+            app:exitAnim="@anim/slide_out_left"/>
         <argument
             android:name="sessionId"
             app:argType="long"

app/src/main/res/values/strings.xml

@@ -290,6 +290,7 @@
     <!--about event fragment-->
     <string name="error_fetching_event_message">Error fetching event</string>
     <string name="error_fetching_events_message">Error fetching events</string>
+    <string name="error_fetching_speakers_for_session">Error fetching speakers under this session</string>
     <string name="error">Error</string>
     <string name="fetch_favorite_events_error_message">Error fetching favorite events</string>
     <string name="list_orders_fail_message">Failed  to list Orders under a user</string>