Merge pull request #605 from nacatl/save-last-session-scroll

Save tab and scroll position which is shown before.(part 2)

app/src/main/java/io/github/droidkaigi/confsched2018/presentation/common/pref/Prefs.kt

@@ -1,11 +1,8 @@
 package io.github.droidkaigi.confsched2018.presentation.common.pref
 
 import com.chibatching.kotpref.KotprefModel
-import com.chibatching.kotpref.enumpref.enumValuePref
 import io.github.droidkaigi.confsched2018.R
-import io.github.droidkaigi.confsched2018.presentation.sessions.SessionTabMode
 import io.github.droidkaigi.confsched2018.util.ext.bool
-import io.github.droidkaigi.confsched2018.util.ext.integer
 
 object Prefs : KotprefModel() {
     public override val kotprefName: String = "droidkaigi_prefs"
@@ -25,14 +22,4 @@ object Prefs : KotprefModel() {
             default = context.bool(R.bool.pref_default_value_enable_reopen_previous_room_sessions),
             key = R.string.pref_key_enable_reopen_previous_room_sessions
     )
-    var previousSessionTabMode by enumValuePref(SessionTabMode.ROOM)
-    var previousSessionTabId: Int by intPref(
-            default = context.integer(R.integer.pref_default_value_previous_session_tab_id)
-    )
-
-    fun initPreviousSessionPrefs() {
-        Prefs.previousSessionTabMode = SessionTabMode.ROOM
-        Prefs.previousSessionTabId = Prefs.context.integer(
-                integerRes = R.integer.pref_default_value_previous_session_tab_id)
-    }
 }

app/src/main/java/io/github/droidkaigi/confsched2018/presentation/common/pref/PreviousSessionPrefs.kt

@@ -0,0 +1,43 @@
+package io.github.droidkaigi.confsched2018.presentation.common.pref
+
+import com.chibatching.kotpref.KotprefModel
+import com.chibatching.kotpref.enumpref.enumValuePref
+import io.github.droidkaigi.confsched2018.R
+import io.github.droidkaigi.confsched2018.presentation.sessions.SessionTabMode
+import io.github.droidkaigi.confsched2018.util.ext.ScrollState
+import io.github.droidkaigi.confsched2018.util.ext.integer
+
+object PreviousSessionPrefs : KotprefModel() {
+    public override val kotprefName: String = "previous_session_prefs"
+    var previousSessionTabMode by enumValuePref(
+            default = SessionTabMode.ROOM
+    )
+    var previousSessionTabId: Int by intPref(
+            default = context.integer(R.integer.pref_default_value_previous_session_tab_id)
+    )
+    private var previousSessionScrollPosition: Int by intPref(
+            default = context.integer(R.integer.pref_default_value_previous_session_scroll_position)
+    )
+    private var previousSessionScrollOffset: Int by intPref(
+            default = context.integer(R.integer.pref_default_value_previous_session_scroll_offset)
+    )
+
+    fun initPreviousSessionPrefs() {
+        PreviousSessionPrefs.previousSessionTabMode = SessionTabMode.ROOM
+        PreviousSessionPrefs.previousSessionTabId = context.integer(
+                integerRes = R.integer.pref_default_value_previous_session_tab_id)
+        PreviousSessionPrefs.previousSessionScrollPosition = context.integer(
+                integerRes = R.integer.pref_default_value_previous_session_scroll_position)
+        PreviousSessionPrefs.previousSessionScrollOffset = context.integer(
+                integerRes = R.integer.pref_default_value_previous_session_scroll_offset)
+    }
+
+    var scrollState: ScrollState
+        get() = ScrollState(
+                anchorPosition = previousSessionScrollPosition,
+                anchorOffset = previousSessionScrollOffset)
+        set(scrollState) {
+            previousSessionScrollPosition = scrollState.anchorPosition
+            previousSessionScrollOffset = scrollState.anchorOffset
+        }
+}

app/src/main/java/io/github/droidkaigi/confsched2018/presentation/sessions/AllSessionsFragment.kt

@@ -20,15 +20,19 @@ import io.github.droidkaigi.confsched2018.di.Injectable
 import io.github.droidkaigi.confsched2018.model.Session
 import io.github.droidkaigi.confsched2018.presentation.NavigationController
 import io.github.droidkaigi.confsched2018.presentation.Result
+import io.github.droidkaigi.confsched2018.presentation.common.pref.PreviousSessionPrefs
 import io.github.droidkaigi.confsched2018.presentation.common.view.OnTabReselectedListener
 import io.github.droidkaigi.confsched2018.presentation.sessions.SessionsFragment.CurrentSessionScroller
+import io.github.droidkaigi.confsched2018.presentation.sessions.SessionsFragment.SavePreviousSessionScroller
 import io.github.droidkaigi.confsched2018.presentation.sessions.item.DateSessionsSection
 import io.github.droidkaigi.confsched2018.presentation.sessions.item.SpeechSessionItem
 import io.github.droidkaigi.confsched2018.util.ProgressTimeLatch
 import io.github.droidkaigi.confsched2018.util.SessionAlarm
 import io.github.droidkaigi.confsched2018.util.ext.addOnScrollListener
+import io.github.droidkaigi.confsched2018.util.ext.getScrollState
 import io.github.droidkaigi.confsched2018.util.ext.isGone
 import io.github.droidkaigi.confsched2018.util.ext.observe
+import io.github.droidkaigi.confsched2018.util.ext.restoreScrollState
 import io.github.droidkaigi.confsched2018.util.ext.setLinearDivider
 import io.github.droidkaigi.confsched2018.util.ext.setTextIfChanged
 import io.github.droidkaigi.confsched2018.util.ext.setVisible
@@ -42,7 +46,8 @@ class AllSessionsFragment :
         Fragment(),
         Injectable,
         CurrentSessionScroller,
-        OnTabReselectedListener {
+        OnTabReselectedListener,
+        SavePreviousSessionScroller {
 
     private lateinit var binding: FragmentAllSessionsBinding
 
@@ -86,7 +91,10 @@ class AllSessionsFragment :
                     sessionsSection.updateSessions(sessions, onFavoriteClickListener,
                             onFeedbackListener, true)
 
-                    sessionsViewModel.onSuccessFetchSessions()
+                    sessionsViewModel.onShowSessions()
+                    if (sessionsViewModel.isNeedRestoreScrollState) {
+                        scrollToPreviousSession()
+                    }
                 }
                 is Result.Failure -> {
                     Timber.e(result.e)
@@ -113,6 +121,26 @@ class AllSessionsFragment :
         binding.sessionsRecycler.smoothScrollToPosition(0)
     }
 
+    override fun requestSavingScrollState() {
+        val layoutManager = binding.sessionsRecycler.layoutManager as LinearLayoutManager
+        PreviousSessionPrefs.scrollState = layoutManager.getScrollState()
+    }
+
+    override fun requestRestoringScrollState() {
+        if (sessionsViewModel.sessions is Result.Success<*>) {
+            scrollToPreviousSession()
+        } else {
+            sessionsViewModel.isNeedRestoreScrollState = true
+        }
+    }
+
+    private fun scrollToPreviousSession() {
+        sessionsViewModel.isNeedRestoreScrollState = false
+        val layoutManager = binding.sessionsRecycler.layoutManager as LinearLayoutManager
+        layoutManager.restoreScrollState(PreviousSessionPrefs.scrollState)
+        PreviousSessionPrefs.initPreviousSessionPrefs()
+    }
+
     private fun setupRecyclerView() {
         val groupAdapter = GroupAdapter<ViewHolder>().apply {
             add(sessionsSection)

app/src/main/java/io/github/droidkaigi/confsched2018/presentation/sessions/AllSessionsViewModel.kt

@@ -26,6 +26,8 @@ class AllSessionsViewModel @Inject constructor(
     private val focusCurrentSession: MutableLiveData<Boolean> = MutableLiveData()
     val refreshFocusCurrentSession: LiveData<Boolean> = focusCurrentSession
 
+    var isNeedRestoreScrollState: Boolean = false
+
     val sessions: LiveData<Result<List<Session>>> by lazy {
         repository.sessions
                 .toResult(schedulerProvider)
@@ -43,7 +45,7 @@ class AllSessionsViewModel @Inject constructor(
                 .addTo(compositeDisposable)
     }
 
-    fun onSuccessFetchSessions() {
+    fun onShowSessions() {
         refreshFocusCurrentSession()
     }
 

app/src/main/java/io/github/droidkaigi/confsched2018/presentation/sessions/RoomSessionsFragment.kt

@@ -21,15 +21,19 @@ import io.github.droidkaigi.confsched2018.model.Room
 import io.github.droidkaigi.confsched2018.model.Session
 import io.github.droidkaigi.confsched2018.presentation.NavigationController
 import io.github.droidkaigi.confsched2018.presentation.Result
+import io.github.droidkaigi.confsched2018.presentation.common.pref.PreviousSessionPrefs
 import io.github.droidkaigi.confsched2018.presentation.common.view.OnTabReselectedListener
 import io.github.droidkaigi.confsched2018.presentation.sessions.SessionsFragment.CurrentSessionScroller
+import io.github.droidkaigi.confsched2018.presentation.sessions.SessionsFragment.SavePreviousSessionScroller
 import io.github.droidkaigi.confsched2018.presentation.sessions.item.DateSessionsSection
 import io.github.droidkaigi.confsched2018.presentation.sessions.item.SpeechSessionItem
 import io.github.droidkaigi.confsched2018.util.ProgressTimeLatch
 import io.github.droidkaigi.confsched2018.util.SessionAlarm
 import io.github.droidkaigi.confsched2018.util.ext.addOnScrollListener
+import io.github.droidkaigi.confsched2018.util.ext.getScrollState
 import io.github.droidkaigi.confsched2018.util.ext.isGone
 import io.github.droidkaigi.confsched2018.util.ext.observe
+import io.github.droidkaigi.confsched2018.util.ext.restoreScrollState
 import io.github.droidkaigi.confsched2018.util.ext.setLinearDivider
 import io.github.droidkaigi.confsched2018.util.ext.setTextIfChanged
 import io.github.droidkaigi.confsched2018.util.ext.setVisible
@@ -43,7 +47,8 @@ class RoomSessionsFragment :
         Fragment(),
         Injectable,
         CurrentSessionScroller,
-        OnTabReselectedListener {
+        OnTabReselectedListener,
+        SavePreviousSessionScroller {
 
     private lateinit var binding: FragmentRoomSessionsBinding
     private lateinit var roomName: String
@@ -94,7 +99,10 @@ class RoomSessionsFragment :
                     sessionsSection.updateSessions(sessions, onFavoriteClickListener,
                             onFeedbackListener, true)
 
-                    sessionsViewModel.onSuccessFetchSessions()
+                    sessionsViewModel.onShowSessions()
+                    if (sessionsViewModel.isNeedRestoreScrollState) {
+                        scrollToPreviousSession()
+                    }
                 }
                 is Result.Failure -> {
                     Timber.e(result.e)
@@ -121,6 +129,26 @@ class RoomSessionsFragment :
         binding.sessionsRecycler.smoothScrollToPosition(0)
     }
 
+    override fun requestSavingScrollState() {
+        val layoutManager = binding.sessionsRecycler.layoutManager as LinearLayoutManager
+        PreviousSessionPrefs.scrollState = layoutManager.getScrollState()
+    }
+
+    override fun requestRestoringScrollState() {
+        if (sessionsViewModel.sessions is Result.Success<*>) {
+            scrollToPreviousSession()
+        } else {
+            sessionsViewModel.isNeedRestoreScrollState = true
+        }
+    }
+
+    private fun scrollToPreviousSession() {
+        sessionsViewModel.isNeedRestoreScrollState = false
+        val layoutManager = binding.sessionsRecycler.layoutManager as LinearLayoutManager
+        layoutManager.restoreScrollState(PreviousSessionPrefs.scrollState)
+        PreviousSessionPrefs.initPreviousSessionPrefs()
+    }
+
     private fun setupRecyclerView() {
         val groupAdapter = GroupAdapter<ViewHolder>().apply {
             add(sessionsSection)

app/src/main/java/io/github/droidkaigi/confsched2018/presentation/sessions/RoomSessionsViewModel.kt

@@ -26,6 +26,9 @@ class RoomSessionsViewModel @Inject constructor(
 
     private val focusCurrentSession: MutableLiveData<Boolean> = MutableLiveData()
     val refreshFocusCurrentSession: LiveData<Boolean> = focusCurrentSession
+
+    var isNeedRestoreScrollState: Boolean = false
+
     lateinit var roomName: String
 
     val sessions: LiveData<Result<List<Session>>> by lazy {
@@ -47,7 +50,7 @@ class RoomSessionsViewModel @Inject constructor(
                 .addTo(compositeDisposable)
     }
 
-    fun onSuccessFetchSessions() {
+    fun onShowSessions() {
         refreshFocusCurrentSession()
     }
 

app/src/main/java/io/github/droidkaigi/confsched2018/presentation/sessions/ScheduleSessionsFragment.kt

@@ -18,17 +18,25 @@ import io.github.droidkaigi.confsched2018.model.Session
 import io.github.droidkaigi.confsched2018.model.SessionSchedule
 import io.github.droidkaigi.confsched2018.presentation.NavigationController
 import io.github.droidkaigi.confsched2018.presentation.Result
+import io.github.droidkaigi.confsched2018.presentation.common.pref.PreviousSessionPrefs
 import io.github.droidkaigi.confsched2018.presentation.common.view.OnTabReselectedListener
+import io.github.droidkaigi.confsched2018.presentation.sessions.SessionsFragment.SavePreviousSessionScroller
 import io.github.droidkaigi.confsched2018.presentation.sessions.item.ScheduleSessionsSection
 import io.github.droidkaigi.confsched2018.presentation.sessions.item.SpeechSessionItem
 import io.github.droidkaigi.confsched2018.util.ProgressTimeLatch
 import io.github.droidkaigi.confsched2018.util.SessionAlarm
+import io.github.droidkaigi.confsched2018.util.ext.getScrollState
 import io.github.droidkaigi.confsched2018.util.ext.observe
+import io.github.droidkaigi.confsched2018.util.ext.restoreScrollState
 import io.github.droidkaigi.confsched2018.util.ext.setLinearDivider
 import timber.log.Timber
 import javax.inject.Inject
 
-class ScheduleSessionsFragment : Fragment(), Injectable, OnTabReselectedListener {
+class ScheduleSessionsFragment :
+        Fragment(),
+        Injectable,
+        OnTabReselectedListener,
+        SavePreviousSessionScroller {
 
     private lateinit var binding: FragmentScheduleSessionsBinding
 
@@ -78,6 +86,9 @@ class ScheduleSessionsFragment : Fragment(), Injectable, OnTabReselectedListener
                     val sessions = result.data
                     sessionsSection.updateSessions(sessions, onFavoriteClickListener,
                             onFeedbackListener)
+                    if (scheduleSessionsViewModel.isNeedRestoreScrollState) {
+                        scrollToPreviousSession()
+                    }
                 }
                 is Result.Failure -> {
                     Timber.e(result.e)
@@ -109,6 +120,26 @@ class ScheduleSessionsFragment : Fragment(), Injectable, OnTabReselectedListener
         binding.sessionsRecycler.smoothScrollToPosition(0)
     }
 
+    override fun requestSavingScrollState() {
+        val layoutManager = binding.sessionsRecycler.layoutManager as LinearLayoutManager
+        PreviousSessionPrefs.scrollState = layoutManager.getScrollState()
+    }
+
+    override fun requestRestoringScrollState() {
+        if (scheduleSessionsViewModel.sessions is Result.Success<*>) {
+            scrollToPreviousSession()
+        } else {
+            scheduleSessionsViewModel.isNeedRestoreScrollState = true
+        }
+    }
+
+    private fun scrollToPreviousSession() {
+        scheduleSessionsViewModel.isNeedRestoreScrollState = false
+        val layoutManager = binding.sessionsRecycler.layoutManager as LinearLayoutManager
+        layoutManager.restoreScrollState(PreviousSessionPrefs.scrollState)
+        PreviousSessionPrefs.initPreviousSessionPrefs()
+    }
+
     companion object {
         private const val ARG_SCHEDULE = "schedule"
 

app/src/main/java/io/github/droidkaigi/confsched2018/presentation/sessions/ScheduleSessionsViewModel.kt

@@ -25,6 +25,8 @@ class ScheduleSessionsViewModel @Inject constructor(
 
     lateinit var schedule: SessionSchedule
 
+    var isNeedRestoreScrollState: Boolean = false
+
     val sessions: LiveData<Result<List<Session>>> by lazy {
         repository.scheduleSessions
                 .map { t: Map<SessionSchedule, List<Session>> ->

app/src/main/java/io/github/droidkaigi/confsched2018/presentation/sessions/SessionsFragment.kt

@@ -27,6 +27,7 @@ import io.github.droidkaigi.confsched2018.presentation.MainActivity.BottomNaviga
 import io.github.droidkaigi.confsched2018.presentation.Result
 import io.github.droidkaigi.confsched2018.presentation.common.fragment.Findable
 import io.github.droidkaigi.confsched2018.presentation.common.pref.Prefs
+import io.github.droidkaigi.confsched2018.presentation.common.pref.PreviousSessionPrefs
 import io.github.droidkaigi.confsched2018.presentation.common.view.OnTabReselectedDispatcher
 import io.github.droidkaigi.confsched2018.util.ProgressTimeLatch
 import io.github.droidkaigi.confsched2018.util.ext.observe
@@ -110,7 +111,7 @@ class SessionsFragment : Fragment(), Injectable, Findable, OnReselectedListener
                 .get(SessionsViewModel::class.java)
 
         if (Prefs.enableReopenPreviousRoomSessions and (savedInstanceState == null)) {
-            sessionsViewModel.changeTabMode(Prefs.previousSessionTabMode)
+            sessionsViewModel.changeTabMode(PreviousSessionPrefs.previousSessionTabMode)
         }
 
         val progressTimeLatch = ProgressTimeLatch {
@@ -159,14 +160,19 @@ class SessionsFragment : Fragment(), Injectable, Findable, OnReselectedListener
         super.onPause()
         when (Prefs.enableReopenPreviousRoomSessions) {
             true -> saveCurrentSession()
-            false -> Prefs.initPreviousSessionPrefs()
+            false -> PreviousSessionPrefs.initPreviousSessionPrefs()
         }
     }
 
     private fun saveCurrentSession() {
         val currentItem = binding.sessionsViewPager.currentItem
-        Prefs.previousSessionTabId = currentItem
-        Prefs.previousSessionTabMode = sessionsViewModel.tabMode
+        PreviousSessionPrefs.previousSessionTabId = currentItem
+        PreviousSessionPrefs.previousSessionTabMode = sessionsViewModel.tabMode
+        val fragment = sessionsViewPagerAdapter
+                .instantiateItem(binding.sessionsViewPager, currentItem)
+        if (fragment is SavePreviousSessionScroller) {
+            fragment.requestSavingScrollState()
+        }
     }
 
     override fun onReselected() {
@@ -188,11 +194,15 @@ class SessionsFragment : Fragment(), Injectable, Findable, OnReselectedListener
     }
 
     private fun reopenPreviousOpenedItem() {
-        val previousItem = Prefs.previousSessionTabId
+        val previousItem = PreviousSessionPrefs.previousSessionTabId
         if (previousItem < 0) return
 
         binding.sessionsViewPager.currentItem = previousItem
-        Prefs.initPreviousSessionPrefs()
+        val fragment = sessionsViewPagerAdapter
+                .instantiateItem(binding.sessionsViewPager, previousItem)
+        if (fragment is SavePreviousSessionScroller) {
+            fragment.requestRestoringScrollState()
+        }
     }
 
     override val tagForFinding = MainActivity.BottomNavigationItem.SESSION.name
@@ -201,6 +211,11 @@ class SessionsFragment : Fragment(), Injectable, Findable, OnReselectedListener
         fun scrollToCurrentSession()
     }
 
+    interface SavePreviousSessionScroller {
+        fun requestSavingScrollState()
+        fun requestRestoringScrollState()
+    }
+
     companion object {
         fun newInstance(): SessionsFragment = SessionsFragment()
     }