Convert TaskListViewModel to flow

app/src/main/java/com/todoroo/astrid/activity/TaskEditFragment.kt

@@ -6,7 +6,6 @@
 package com.todoroo.astrid.activity
 
 import android.app.Activity
-import android.content.BroadcastReceiver
 import android.content.Context
 import android.content.Intent
 import android.graphics.Paint
@@ -16,15 +15,20 @@ import android.view.LayoutInflater
 import android.view.MenuItem
 import android.view.View
 import android.view.ViewGroup
+import android.view.inputmethod.EditorInfo
 import android.view.inputmethod.InputMethodManager
 import androidx.activity.result.contract.ActivityResultContracts
 import androidx.appcompat.content.res.AppCompatResources
 import androidx.appcompat.widget.Toolbar
 import androidx.compose.animation.ExperimentalAnimationApi
-import androidx.compose.foundation.layout.*
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.material.Divider
-import androidx.compose.runtime.*
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.saveable.rememberSaveable
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.input.pointer.PointerEventPass
 import androidx.compose.ui.input.pointer.pointerInput
@@ -55,19 +59,32 @@ import kotlinx.coroutines.flow.launchIn
 import kotlinx.coroutines.flow.onEach
 import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.launch
-import org.tasks.LocalBroadcastManager
 import org.tasks.R
 import org.tasks.Strings.isNullOrEmpty
 import org.tasks.analytics.Firebase
 import org.tasks.calendars.CalendarPicker
 import org.tasks.compose.BeastModeBanner
 import org.tasks.compose.collectAsStateLifecycleAware
-import org.tasks.compose.edit.*
+import org.tasks.compose.edit.CommentsRow
+import org.tasks.compose.edit.DescriptionRow
+import org.tasks.compose.edit.DueDateRow
+import org.tasks.compose.edit.InfoRow
+import org.tasks.compose.edit.ListRow
+import org.tasks.compose.edit.PriorityRow
 import org.tasks.data.Alarm
 import org.tasks.data.Location
 import org.tasks.data.TagData
 import org.tasks.data.UserActivityDao
-import org.tasks.databinding.*
+import org.tasks.databinding.FragmentTaskEditBinding
+import org.tasks.databinding.TaskEditCalendarBinding
+import org.tasks.databinding.TaskEditFilesBinding
+import org.tasks.databinding.TaskEditLocationBinding
+import org.tasks.databinding.TaskEditRemindersBinding
+import org.tasks.databinding.TaskEditRepeatBinding
+import org.tasks.databinding.TaskEditStartDateBinding
+import org.tasks.databinding.TaskEditSubtasksBinding
+import org.tasks.databinding.TaskEditTagsBinding
+import org.tasks.databinding.TaskEditTimerBinding
 import org.tasks.date.DateTimeUtils.newDateTime
 import org.tasks.dialogs.DateTimePicker
 import org.tasks.dialogs.DialogBuilder
@@ -84,13 +101,18 @@ import org.tasks.fragments.TaskEditControlSetFragmentManager.Companion.TAG_PRIOR
 import org.tasks.markdown.MarkdownProvider
 import org.tasks.notifications.NotificationManager
 import org.tasks.preferences.Preferences
-import org.tasks.ui.*
+import org.tasks.ui.CalendarControlSet
+import org.tasks.ui.ChipProvider
+import org.tasks.ui.LocationControlSet
+import org.tasks.ui.SubtaskControlSet
+import org.tasks.ui.TaskEditEvent
+import org.tasks.ui.TaskEditEventBus
+import org.tasks.ui.TaskEditViewModel
 import org.tasks.ui.TaskEditViewModel.Companion.stripCarriageReturns
 import java.time.format.FormatStyle
-import java.util.*
+import java.util.Locale
 import javax.inject.Inject
 import kotlin.math.abs
-import android.view.inputmethod.EditorInfo
 
 @AndroidEntryPoint
 class TaskEditFragment : Fragment(), Toolbar.OnMenuItemClickListener {
@@ -106,15 +128,12 @@ class TaskEditFragment : Fragment(), Toolbar.OnMenuItemClickListener {
     @Inject lateinit var linkify: Linkify
     @Inject lateinit var markdownProvider: MarkdownProvider
     @Inject lateinit var taskEditEventBus: TaskEditEventBus
-    @Inject lateinit var localBroadcastManager: LocalBroadcastManager
     @Inject lateinit var locale: Locale
     @Inject lateinit var chipProvider: ChipProvider
 
     val editViewModel: TaskEditViewModel by viewModels()
-    val subtaskViewModel: TaskListViewModel by viewModels()
     lateinit var binding: FragmentTaskEditBinding
     private var showKeyboard = false
-    private val refreshReceiver = RefreshReceiver()
     private val beastMode =
         registerForActivityResult(ActivityResultContracts.StartActivityForResult()) {
             activity?.recreate()
@@ -317,7 +336,6 @@ class TaskEditFragment : Fragment(), Toolbar.OnMenuItemClickListener {
 
     override fun onResume() {
         super.onResume()
-        localBroadcastManager.registerRefreshReceiver(refreshReceiver)
         if (showKeyboard) {
             binding.title.requestFocus()
             val imm = context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
@@ -328,11 +346,6 @@ class TaskEditFragment : Fragment(), Toolbar.OnMenuItemClickListener {
         }
     }
 
-    override fun onPause() {
-        super.onPause()
-        localBroadcastManager.unregisterReceiver(refreshReceiver)
-    }
-
     override fun onMenuItemClick(item: MenuItem): Boolean {
         AndroidUtilities.hideKeyboard(activity)
         if (item.itemId == R.id.menu_delete) {
@@ -417,12 +430,6 @@ class TaskEditFragment : Fragment(), Toolbar.OnMenuItemClickListener {
         }
     }
 
-    private inner class RefreshReceiver : BroadcastReceiver() {
-        override fun onReceive(context: Context, intent: Intent) {
-            subtaskViewModel.invalidate()
-        }
-    }
-
     @Composable
     private fun DueDateRow() {
         val dueDate = editViewModel.dueDate.collectAsStateLifecycleAware().value

app/src/main/java/com/todoroo/astrid/activity/TaskListFragment.kt

@@ -12,7 +12,12 @@ import android.content.Intent
 import android.os.Bundle
 import android.os.Parcelable
 import android.speech.RecognizerIntent
-import android.view.*
+import android.view.Gravity
+import android.view.LayoutInflater
+import android.view.Menu
+import android.view.MenuItem
+import android.view.View
+import android.view.ViewGroup
 import androidx.annotation.StringRes
 import androidx.appcompat.app.AppCompatActivity
 import androidx.appcompat.view.ActionMode
@@ -30,7 +35,9 @@ import androidx.core.view.isVisible
 import androidx.core.view.setMargins
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.viewModels
+import androidx.lifecycle.Lifecycle
 import androidx.lifecycle.lifecycleScope
+import androidx.lifecycle.repeatOnLifecycle
 import androidx.recyclerview.widget.DefaultItemAnimator
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
@@ -45,20 +52,33 @@ import com.todoroo.andlib.utility.DateUtilities
 import com.todoroo.andlib.utility.DateUtilities.now
 import com.todoroo.astrid.adapter.TaskAdapter
 import com.todoroo.astrid.adapter.TaskAdapterProvider
-import com.todoroo.astrid.api.*
 import com.todoroo.astrid.api.AstridApiConstants.EXTRAS_OLD_DUE_DATE
 import com.todoroo.astrid.api.AstridApiConstants.EXTRAS_TASK_ID
+import com.todoroo.astrid.api.CaldavFilter
+import com.todoroo.astrid.api.Filter
+import com.todoroo.astrid.api.GtasksFilter
+import com.todoroo.astrid.api.IdListFilter
+import com.todoroo.astrid.api.SearchFilter
+import com.todoroo.astrid.api.TagFilter
 import com.todoroo.astrid.core.BuiltInFilterExposer
 import com.todoroo.astrid.dao.TaskDao
 import com.todoroo.astrid.data.Task
 import com.todoroo.astrid.repeats.RepeatTaskHelper
-import com.todoroo.astrid.service.*
+import com.todoroo.astrid.service.TaskCompleter
+import com.todoroo.astrid.service.TaskCreator
+import com.todoroo.astrid.service.TaskDeleter
+import com.todoroo.astrid.service.TaskDuplicator
+import com.todoroo.astrid.service.TaskMover
 import com.todoroo.astrid.timers.TimerPlugin
 import com.todoroo.astrid.utility.Flags
 import dagger.hilt.android.AndroidEntryPoint
-import kotlinx.coroutines.*
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.NonCancellable
+import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.launchIn
 import kotlinx.coroutines.flow.onEach
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
 import org.tasks.LocalBroadcastManager
 import org.tasks.R
 import org.tasks.ShortcutManager
@@ -93,12 +113,18 @@ import org.tasks.preferences.Device
 import org.tasks.preferences.Preferences
 import org.tasks.sync.SyncAdapters
 import org.tasks.tags.TagPickerActivity
-import org.tasks.tasklist.*
+import org.tasks.tasklist.DragAndDropRecyclerAdapter
+import org.tasks.tasklist.TaskViewHolder
+import org.tasks.tasklist.ViewHolderFactory
 import org.tasks.themes.ColorProvider
 import org.tasks.themes.ThemeColor
-import org.tasks.ui.*
+import org.tasks.ui.TaskEditEvent
+import org.tasks.ui.TaskEditEventBus
+import org.tasks.ui.TaskListEvent
+import org.tasks.ui.TaskListEventBus
+import org.tasks.ui.TaskListViewModel
 import java.time.format.FormatStyle
-import java.util.*
+import java.util.Locale
 import javax.inject.Inject
 import kotlin.math.max
 
@@ -263,14 +289,18 @@ class TaskListFragment : Fragment(), OnRefreshListener, Toolbar.OnMenuItemClickL
         listViewModel.setFilter((if (searchQuery == null) filter else createSearchFilter(searchQuery!!)))
         (recyclerView.itemAnimator as DefaultItemAnimator).supportsChangeAnimations = false
         recyclerView.layoutManager = LinearLayoutManager(context)
-        listViewModel.observe(this) {
-            submitList(it)
-            if (it.isEmpty()) {
-                swipeRefreshLayout.visibility = View.GONE
-                emptyRefreshLayout.visibility = View.VISIBLE
-            } else {
-                swipeRefreshLayout.visibility = View.VISIBLE
-                emptyRefreshLayout.visibility = View.GONE
+        lifecycleScope.launch {
+            viewLifecycleOwner.repeatOnLifecycle(Lifecycle.State.STARTED) {
+                listViewModel.tasks.collect {
+                    submitList(it)
+                    if (it.isEmpty()) {
+                        swipeRefreshLayout.visibility = View.GONE
+                        emptyRefreshLayout.visibility = View.VISIBLE
+                    } else {
+                        swipeRefreshLayout.visibility = View.VISIBLE
+                        emptyRefreshLayout.visibility = View.GONE
+                    }
+                }
             }
         }
         setupRefresh(swipeRefreshLayout)
@@ -383,11 +413,11 @@ class TaskListFragment : Fragment(), OnRefreshListener, Toolbar.OnMenuItemClickL
             delay(SEARCH_DEBOUNCE_TIMEOUT)
             searchQuery = query?.trim { it <= ' ' } ?: ""
             if (searchQuery?.isEmpty() == true) {
-                listViewModel.searchByFilter(
+                listViewModel.setFilter(
                     BuiltInFilterExposer.getMyTasksFilter(requireContext().resources))
             } else {
                 val savedFilter = createSearchFilter(searchQuery!!)
-                listViewModel.searchByFilter(savedFilter)
+                listViewModel.setFilter(savedFilter)
             }
         }
     }
@@ -572,7 +602,6 @@ class TaskListFragment : Fragment(), OnRefreshListener, Toolbar.OnMenuItemClickL
     }
 
     private fun refresh() {
-        loadTaskListContent()
         setSyncOngoing()
     }
 
@@ -666,7 +695,7 @@ class TaskListFragment : Fragment(), OnRefreshListener, Toolbar.OnMenuItemClickL
 
     override fun onMenuItemActionCollapse(item: MenuItem): Boolean {
         search.setOnQueryTextListener(null)
-        listViewModel.searchByFilter(filter)
+        listViewModel.setFilter(filter)
         searchJob?.cancel()
         searchQuery = null
         if (preferences.isTopAppBar) {

app/src/main/java/org/tasks/compose/FlowHelpers.kt

@@ -8,11 +8,21 @@ import androidx.compose.ui.platform.LocalLifecycleOwner
 import androidx.lifecycle.Lifecycle
 import androidx.lifecycle.LifecycleOwner
 import androidx.lifecycle.flowWithLifecycle
+import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.conflate
+import kotlinx.coroutines.flow.flow
 import kotlin.coroutines.CoroutineContext
 import kotlin.coroutines.EmptyCoroutineContext
 
+fun <T> Flow<T>.throttleLatest(period: Long) = flow {
+    conflate().collect {
+        emit(it)
+        delay(period)
+    }
+}
+
 // https://proandroiddev.com/how-to-collect-flows-lifecycle-aware-in-jetpack-compose-babd53582d0b
 
 @Composable

app/src/main/java/org/tasks/ui/SubtaskControlSet.kt

@@ -4,7 +4,6 @@ import android.app.Activity
 import android.os.Bundle
 import android.view.View
 import android.view.ViewGroup
-import androidx.compose.runtime.livedata.observeAsState
 import androidx.compose.ui.platform.ComposeView
 import androidx.lifecycle.ViewModelProvider
 import androidx.lifecycle.lifecycleScope
@@ -59,7 +58,7 @@ class SubtaskControlSet : TaskEditControlFragment() {
                         filter = viewModel.selectedList.collectAsStateLifecycleAware().value,
                         hasParent = viewModel.hasParent,
                         desaturate = preferences.desaturateDarkMode,
-                        existingSubtasks = listViewModel.tasks.observeAsState(initial = emptyList()).value,
+                        existingSubtasks = listViewModel.tasks.collectAsStateLifecycleAware(initial = emptyList()).value,
                         newSubtasks = viewModel.newSubtasks.collectAsStateLifecycleAware().value,
                         openSubtask = this@SubtaskControlSet::openSubtask,
                         completeExistingSubtask = this@SubtaskControlSet::complete,

app/src/main/java/org/tasks/ui/TaskListViewModel.kt

@@ -1,64 +1,66 @@
 package org.tasks.ui
 
-import androidx.lifecycle.LifecycleOwner
-import androidx.lifecycle.LiveData
-import androidx.lifecycle.MutableLiveData
+import android.content.BroadcastReceiver
+import android.content.Context
+import android.content.Intent
 import androidx.lifecycle.ViewModel
-import androidx.lifecycle.viewModelScope
-import com.todoroo.andlib.utility.AndroidUtilities
+import com.todoroo.andlib.utility.DateUtilities
 import com.todoroo.astrid.api.Filter
 import dagger.hilt.android.lifecycle.HiltViewModel
-import kotlinx.coroutines.launch
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.filter
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.update
+import org.tasks.LocalBroadcastManager
+import org.tasks.compose.throttleLatest
 import org.tasks.data.TaskContainer
 import org.tasks.data.TaskDao
 import org.tasks.data.TaskListQuery.getQuery
 import org.tasks.preferences.Preferences
-import timber.log.Timber
 import javax.inject.Inject
 
 @HiltViewModel
 class TaskListViewModel @Inject constructor(
         private val preferences: Preferences,
-        private val taskDao: TaskDao) : ViewModel() {
+        private val taskDao: TaskDao,
+        private val localBroadcastManager: LocalBroadcastManager,
+) : ViewModel() {
 
-    private var _tasks = MutableLiveData<List<TaskContainer>>()
-    val tasks: LiveData<List<TaskContainer>>
-        get() = _tasks
-    private var filter: Filter? = null
-    private var manualSortFilter = false
+    data class State(
+        val filter: Filter? = null,
+        val now: Long = DateUtilities.now(),
+    )
 
-    fun setFilter(filter: Filter) {
-        manualSortFilter = (filter.supportsManualSort() && preferences.isManualSort
-                || filter.supportsAstridSorting() && preferences.isAstridSort)
-        if (filter != this.filter || filter.getSqlQuery() != this.filter!!.getSqlQuery()) {
-            this.filter = filter
-            _tasks = MutableLiveData()
+    private val _state = MutableStateFlow(State())
+
+    val tasks: Flow<List<TaskContainer>> =
+        _state
+            .filter { it.filter != null }
+            .throttleLatest(333)
+            .map { taskDao.fetchTasks { getQuery(preferences, it.filter!!) } }
+
+    private val refreshReceiver = object : BroadcastReceiver() {
+        override fun onReceive(context: Context?, intent: Intent?) {
             invalidate()
         }
     }
 
-    fun observe(owner: LifecycleOwner, observer: (List<TaskContainer>) -> Unit) =
-            _tasks.observe(owner, observer)
-
-    fun searchByFilter(filter: Filter?) {
-        this.filter = filter
-        invalidate()
+    fun setFilter(filter: Filter) {
+        _state.update {
+            it.copy(filter = filter)
+        }
     }
 
     fun invalidate() {
-        AndroidUtilities.assertMainThread()
-        if (filter == null) {
-            return
-        }
-        try {
-            viewModelScope.launch {
-                _tasks.value = taskDao.fetchTasks { getQuery(preferences, filter!!) }
-            }
-        } catch (e: Exception) {
-            Timber.e(e)
-        }
+        _state.update { it.copy(now = DateUtilities.now()) }
     }
 
-    val value: List<TaskContainer>
-        get() = _tasks.value ?: emptyList()
-}
+    init {
+        localBroadcastManager.registerRefreshReceiver(refreshReceiver)
+    }
+
+    override fun onCleared() {
+        localBroadcastManager.unregisterReceiver(refreshReceiver)
+    }
+}