Add sort by list

app/src/main/java/com/todoroo/astrid/core/SortHelper.java

@@ -17,6 +17,7 @@ import com.todoroo.andlib.sql.Functions;
 import com.todoroo.andlib.sql.Order;
 import com.todoroo.astrid.data.Task;
 
+import org.tasks.data.CaldavCalendar;
 import org.tasks.preferences.QueryPreferences;
 
 import java.util.Locale;
@@ -37,6 +38,7 @@ public class SortHelper {
   public static final int SORT_GTASKS = 6;
   public static final int SORT_CALDAV = 7;
   public static final int SORT_START = 8;
+  public static final int SORT_LIST = 9;
 
   public static final long APPLE_EPOCH = 978307200000L; // 1/1/2001 GMT
   @SuppressLint("DefaultLocale")
@@ -48,6 +50,7 @@ public class SortHelper {
   private static final String ADJUSTED_START_DATE =
       "(CASE WHEN (hideUntil / 1000) % 60 > 0 THEN hideUntil ELSE (hideUntil + 86399000) END)";
   private static final Order ORDER_TITLE = Order.asc(Functions.upper(Task.TITLE));
+  private static final Order ORDER_LIST = Order.asc(Functions.upper(CaldavCalendar.NAME));
 
   /** Takes a SQL query, and if there isn't already an order, creates an order. */
   public static String adjustQueryForFlagsAndSort(
@@ -113,6 +116,9 @@ public class SortHelper {
       case SORT_CREATED:
         order = Order.desc(Task.CREATION_DATE);
         break;
+      case SORT_LIST:
+        order = ORDER_LIST;
+        break;
       default:
         order =
             Order.asc(
@@ -146,6 +152,8 @@ public class SortHelper {
         return "tasks.modified";
       case SORT_CREATED:
         return "tasks.created";
+      case SORT_LIST:
+        return "cdl_id";
       default:
         return null;
     }
@@ -168,6 +176,7 @@ public class SortHelper {
       case SORT_CREATED -> "tasks.created";
       case SORT_GTASKS -> "tasks.`order`";
       case SORT_CALDAV -> CALDAV_ORDER_COLUMN;
+      case SORT_LIST -> "cdl_name";
       default -> "(CASE WHEN (tasks.dueDate=0) "
               + // if no due date
               "THEN (strftime('%s','now')*1000)*2 "

app/src/main/java/org/tasks/data/CaldavCalendar.kt

@@ -51,6 +51,6 @@ data class CaldavCalendar(
         val TABLE = Table("caldav_lists")
         val ACCOUNT = TABLE.column("cdl_account")
         val UUID = TABLE.column("cdl_uuid")
-        val NAME = TABLE.column("cdl_name")
+        @JvmField val NAME = TABLE.column("cdl_name")
     }
 }

app/src/main/java/org/tasks/data/CaldavDao.kt

@@ -33,6 +33,9 @@ abstract class CaldavDao {
     @Query("SELECT * FROM caldav_lists WHERE cdl_uuid = :uuid LIMIT 1")
     abstract suspend fun getCalendarByUuid(uuid: String): CaldavCalendar?
 
+    @Query("SELECT * FROM caldav_lists WHERE cdl_id = :id LIMIT 1")
+    abstract suspend fun getCalendarById(id: Long): CaldavCalendar?
+
     @Query("SELECT * FROM caldav_lists WHERE cdl_account = :uuid")
     abstract suspend fun getCalendarsByAccount(uuid: String): List<CaldavCalendar>
 

app/src/main/java/org/tasks/data/TaskListQueryRecursive.kt

@@ -48,14 +48,22 @@ internal object TaskListQueryRecursive {
             else -> PermaSql.replacePlaceholdersForQuery(filter.getSqlQuery())
         }
         val manualSort = preferences.isManualSort
+        val sortPreference = preferences.sortMode
         val sortMode = when {
             manualSort && filter is GtasksFilter -> SortHelper.SORT_GTASKS
             manualSort && filter is CaldavFilter -> SortHelper.SORT_CALDAV
-            else -> preferences.sortMode
+            sortPreference == SortHelper.SORT_LIST && (filter is GtasksFilter || filter is CaldavFilter) ->
+                SortHelper.SORT_AUTO
+            else -> sortPreference
         }
         val reverseSort =
             preferences.isReverseSort && sortMode != SortHelper.SORT_GTASKS && sortMode != SortHelper.SORT_CALDAV
-        val sortSelect = SortHelper.orderSelectForSortTypeRecursive(sortMode)
+        val primarySortSelect = SortHelper.orderSelectForSortTypeRecursive(sortMode)
+        val secondarySortSelect = if (sortMode == SortHelper.SORT_LIST) {
+            "NULL"
+        } else {
+            primarySortSelect
+        }
         val parentCompleted = if (preferences.completedTasksAtBottom) "tasks.completed > 0" else "0"
         val completionSort =
             if (preferences.completedTasksAtBottom && preferences.sortCompletedByCompletionDate) {
@@ -66,10 +74,20 @@ internal object TaskListQueryRecursive {
         val withClause = """
             CREATE TEMPORARY TABLE `recursive_tasks` AS
             WITH RECURSIVE recursive_tasks (task, parent_complete, subtask_complete, completion_sort, parent, collapsed, hidden, indent, title, primary_sort, secondary_sort, sort_group) AS (
-                SELECT tasks._id, $parentCompleted as parent_complete, 0 as subtask_complete, $completionSort as completion_sort, 0 as parent, tasks.collapsed as collapsed, 0 as hidden, 0 AS sort_indent, UPPER(tasks.title) AS sort_title, $sortSelect as primary_sort, NULL as secondarySort, ${SortHelper.getSortGroup(sortMode)}
+                SELECT tasks._id, $parentCompleted as parent_complete, 0 as subtask_complete, $completionSort as completion_sort, 0 as parent, tasks.collapsed as collapsed, 0 as hidden, 0 AS sort_indent, UPPER(tasks.title) AS sort_title, $primarySortSelect as primary_sort, NULL as secondarySort, ${SortHelper.getSortGroup(sortMode)}
                 FROM tasks
+                ${
+                    if (sortMode == SortHelper.SORT_LIST) {
+                        """
+                            LEFT JOIN caldav_tasks on cd_task = tasks._id AND cd_deleted = 0
+                            LEFT JOIN caldav_lists on cd_calendar = cdl_uuid
+                        """.trimIndent()
+                    } else {
+                        ""
+                    }
+                }
                 $parentQuery
-                UNION ALL SELECT tasks._id, recursive_tasks.parent_complete, $parentCompleted as subtask_complete, $completionSort as completion_sort, recursive_tasks.task as parent, tasks.collapsed as collapsed, CASE WHEN recursive_tasks.collapsed > 0 OR recursive_tasks.hidden > 0 THEN 1 ELSE 0 END as hidden, recursive_tasks.indent+1 AS sort_indent, UPPER(tasks.title) AS sort_title, recursive_tasks.primary_sort as primary_sort, $sortSelect as secondary_sort, recursive_tasks.sort_group FROM tasks
+                UNION ALL SELECT tasks._id, recursive_tasks.parent_complete, $parentCompleted as subtask_complete, $completionSort as completion_sort, recursive_tasks.task as parent, tasks.collapsed as collapsed, CASE WHEN recursive_tasks.collapsed > 0 OR recursive_tasks.hidden > 0 THEN 1 ELSE 0 END as hidden, recursive_tasks.indent+1 AS sort_indent, UPPER(tasks.title) AS sort_title, recursive_tasks.primary_sort as primary_sort, $secondarySortSelect as secondary_sort, recursive_tasks.sort_group FROM tasks
                 $SUBTASK_QUERY
                 ORDER BY parent_complete ASC, sort_indent DESC, subtask_complete ASC, completion_sort DESC, ${SortHelper.orderForSortTypeRecursive(sortMode, reverseSort)}
             ) SELECT * FROM recursive_tasks

app/src/main/java/org/tasks/dialogs/SortDialog.java

@@ -7,20 +7,26 @@ import android.app.Dialog;
 import android.content.DialogInterface;
 import android.os.Bundle;
 import android.widget.Button;
+
 import androidx.annotation.NonNull;
 import androidx.appcompat.app.AlertDialog;
 import androidx.fragment.app.DialogFragment;
 import androidx.fragment.app.Fragment;
+
 import com.todoroo.astrid.api.Filter;
 import com.todoroo.astrid.core.SortHelper;
-import dagger.hilt.android.AndroidEntryPoint;
+
-import java.util.ArrayList;
-import java.util.List;
-import javax.inject.Inject;
 import org.tasks.R;
 import org.tasks.preferences.Preferences;
 import org.tasks.preferences.QueryPreferences;
 import org.tasks.widget.WidgetPreferences;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.inject.Inject;
+
+import dagger.hilt.android.AndroidEntryPoint;
 import timber.log.Timber;
 
 @AndroidEntryPoint
@@ -92,6 +98,7 @@ public class SortDialog extends DialogFragment {
     items.add(getString(R.string.SSD_sort_alpha));
     items.add(getString(R.string.SSD_sort_modified));
     items.add(getString(R.string.sort_created));
+    items.add(getString(R.string.sort_list));
 
     if (manualEnabled) {
       if (preferences.isManualSort()) {
@@ -186,6 +193,8 @@ public class SortDialog extends DialogFragment {
         return 6;
       case SortHelper.SORT_CREATED:
         return 7;
+      case SortHelper.SORT_LIST:
+        return 8;
     }
 
     Timber.e("Invalid sort mode: %s", sortMode);
@@ -208,6 +217,8 @@ public class SortDialog extends DialogFragment {
         return SortHelper.SORT_MODIFIED;
       case 7:
         return SortHelper.SORT_CREATED;
+      case 8:
+        return SortHelper.SORT_LIST;
     }
 
     Timber.e("Invalid sort mode: %s", index);

app/src/main/java/org/tasks/tasklist/AdapterSection.kt

@@ -1,16 +1,10 @@
 package org.tasks.tasklist
 
 import android.content.Context
-import androidx.annotation.StringRes
 import androidx.core.content.ContextCompat
-import com.todoroo.andlib.utility.DateUtilities
+import com.todoroo.astrid.core.SortHelper.SORT_START
-import com.todoroo.astrid.core.SortHelper.*
 import org.tasks.R
 import org.tasks.date.DateTimeUtils.toDateTime
-import org.tasks.tasklist.SectionedDataSource.Companion.HEADER_COMPLETED
-import org.tasks.tasklist.SectionedDataSource.Companion.HEADER_OVERDUE
-import java.time.format.FormatStyle
-import java.util.*
 
 data class AdapterSection(
         var firstPosition: Int,
@@ -26,48 +20,4 @@ data class AdapterSection(
             } else {
                 textColor
             })
-
-    fun headerString(
-            context: Context,
-            locale: Locale,
-            sortMode: Int,
-            alwaysDisplayFullDate: Boolean,
-            style: FormatStyle = FormatStyle.FULL,
-            compact: Boolean = false
-    ): String =
-            when {
-                value == HEADER_COMPLETED -> context.getString(R.string.completed)
-                sortMode == SORT_IMPORTANCE -> context.getString(priorityToString())
-                value == HEADER_OVERDUE -> context.getString(R.string.filter_overdue)
-                value == 0L -> context.getString(when (sortMode) {
-                    SORT_DUE -> R.string.no_due_date
-                    SORT_START -> R.string.no_start_date
-                    else -> R.string.no_date
-                })
-                else -> {
-                    val dateString = DateUtilities.getRelativeDay(
-                            context, value, locale, style, alwaysDisplayFullDate, !compact
-                    )
-                    when {
-                        compact -> dateString
-                        sortMode == SORT_DUE ->
-                            context.getString(R.string.sort_due_group, dateString)
-                        sortMode == SORT_START ->
-                            context.getString(R.string.sort_start_group, dateString)
-                        sortMode == SORT_CREATED ->
-                            context.getString(R.string.sort_created_group, dateString)
-                        sortMode == SORT_MODIFIED ->
-                            context.getString(R.string.sort_modified_group, dateString)
-                        else -> throw IllegalArgumentException()
-                    }
-                }
-            }
-
-    @StringRes
-    private fun priorityToString() = when (value) {
-        0L -> R.string.filter_high_priority
-        1L -> R.string.filter_medium_priority
-        2L -> R.string.filter_low_priority
-        else -> R.string.filter_no_priority
-    }
 }

app/src/main/java/org/tasks/tasklist/DragAndDropRecyclerAdapter.kt

@@ -4,8 +4,13 @@ import android.graphics.Canvas
 import android.view.ViewGroup
 import androidx.recyclerview.widget.DiffUtil
 import androidx.recyclerview.widget.ItemTouchHelper
-import androidx.recyclerview.widget.ItemTouchHelper.*
+import androidx.recyclerview.widget.ItemTouchHelper.ACTION_STATE_DRAG
+import androidx.recyclerview.widget.ItemTouchHelper.Callback
 import androidx.recyclerview.widget.ItemTouchHelper.Callback.makeMovementFlags
+import androidx.recyclerview.widget.ItemTouchHelper.DOWN
+import androidx.recyclerview.widget.ItemTouchHelper.LEFT
+import androidx.recyclerview.widget.ItemTouchHelper.RIGHT
+import androidx.recyclerview.widget.ItemTouchHelper.UP
 import androidx.recyclerview.widget.RecyclerView
 import com.todoroo.astrid.activity.TaskListFragment
 import com.todoroo.astrid.adapter.TaskAdapter
@@ -18,7 +23,8 @@ import kotlinx.coroutines.runBlocking
 import org.tasks.activities.DragAndDropDiffer
 import org.tasks.data.TaskContainer
 import org.tasks.preferences.Preferences
-import java.util.*
+import java.util.LinkedList
+import java.util.Queue
 import java.util.concurrent.Executors
 import kotlin.math.max
 import kotlin.math.min
@@ -50,7 +56,7 @@ class DragAndDropRecyclerAdapter(
         val viewType = getItemViewType(position)
         if (viewType == 1) {
             val headerSection = items.getSection(position)
-            (holder as HeaderViewHolder).bind(taskList.getFilter(), preferences.sortMode, preferences.alwaysDisplayFullDate, headerSection)
+            (holder as HeaderViewHolder).bind(taskList.getFilter(), preferences.sortMode, headerSection)
         } else {
             super.onBindViewHolder(holder, position)
         }

app/src/main/java/org/tasks/tasklist/HeaderFormatter.kt

@@ -0,0 +1,77 @@
+package org.tasks.tasklist
+
+import android.content.Context
+import androidx.annotation.StringRes
+import com.todoroo.andlib.utility.DateUtilities
+import com.todoroo.astrid.core.SortHelper
+import dagger.hilt.android.qualifiers.ApplicationContext
+import kotlinx.coroutines.runBlocking
+import org.tasks.R
+import org.tasks.data.CaldavDao
+import org.tasks.preferences.Preferences
+import java.time.format.FormatStyle
+import java.util.Locale
+import javax.inject.Inject
+
+class HeaderFormatter @Inject constructor(
+    @ApplicationContext private val context: Context,
+    private val preferences: Preferences,
+    private val locale: Locale,
+    private val caldavDao: CaldavDao,
+) {
+    private val listCache = HashMap<Long, String?>()
+
+    fun headerStringBlocking(
+        value: Long,
+        sortMode: Int = preferences.sortMode,
+        alwaysDisplayFullDate: Boolean = preferences.alwaysDisplayFullDate,
+        style: FormatStyle = FormatStyle.FULL,
+        compact: Boolean = false,
+    ) = runBlocking {
+        headerString(value, sortMode, alwaysDisplayFullDate, style, compact)
+    }
+
+    suspend fun headerString(
+        value: Long,
+        sortMode: Int = preferences.sortMode,
+        alwaysDisplayFullDate: Boolean = preferences.alwaysDisplayFullDate,
+        style: FormatStyle = FormatStyle.FULL,
+        compact: Boolean = false
+    ): String =
+        when {
+            value == SectionedDataSource.HEADER_COMPLETED -> context.getString(R.string.completed)
+            sortMode == SortHelper.SORT_IMPORTANCE -> context.getString(priorityToString(value))
+            sortMode == SortHelper.SORT_LIST ->
+                listCache.getOrPut(value) { caldavDao.getCalendarById(value)?.name }?: "list: $value"
+            value == SectionedDataSource.HEADER_OVERDUE -> context.getString(R.string.filter_overdue)
+            value == 0L -> context.getString(when (sortMode) {
+                SortHelper.SORT_DUE -> R.string.no_due_date
+                SortHelper.SORT_START -> R.string.no_start_date
+                else -> R.string.no_date
+            })
+            else -> {
+                val dateString = DateUtilities.getRelativeDay(
+                    context, value, locale, style, alwaysDisplayFullDate, !compact
+                )
+                when {
+                    compact -> dateString
+                    sortMode == SortHelper.SORT_DUE ->
+                        context.getString(R.string.sort_due_group, dateString)
+                    sortMode == SortHelper.SORT_START ->
+                        context.getString(R.string.sort_start_group, dateString)
+                    sortMode == SortHelper.SORT_CREATED ->
+                        context.getString(R.string.sort_created_group, dateString)
+                    sortMode == SortHelper.SORT_MODIFIED ->
+                        context.getString(R.string.sort_modified_group, dateString)
+                    else -> throw IllegalArgumentException()
+                }
+            }
+        }
+    @StringRes
+    private fun priorityToString(value: Long) = when (value) {
+        0L -> R.string.filter_high_priority
+        1L -> R.string.filter_medium_priority
+        2L -> R.string.filter_low_priority
+        else -> R.string.filter_no_priority
+    }
+}

app/src/main/java/org/tasks/tasklist/HeaderViewHolder.kt

@@ -7,11 +7,10 @@ import android.widget.TextView
 import androidx.recyclerview.widget.RecyclerView
 import com.todoroo.astrid.api.Filter
 import org.tasks.R
-import java.util.*
 
 class HeaderViewHolder(
         private val context: Context,
-        private val locale: Locale,
+        private val headerFormatter: HeaderFormatter,
         view: View,
         callback: (Long) -> Unit
 ) : RecyclerView.ViewHolder(view) {
@@ -21,10 +20,10 @@ class HeaderViewHolder(
     private var sortGroup = -1L
     private var rotation = 0f
 
-    fun bind(filter: Filter, sortMode: Int, alwaysDisplayFullDate: Boolean, section: AdapterSection) {
+    fun bind(filter: Filter, sortMode: Int, section: AdapterSection) {
         sortGroup = section.value
         val header = if (filter.supportsSorting()) {
-            section.headerString(context, locale, sortMode, alwaysDisplayFullDate)
+            headerFormatter.headerStringBlocking(section.value)
         } else {
             null
         }

app/src/main/java/org/tasks/tasklist/SectionedDataSource.kt

@@ -66,7 +66,11 @@ class SectionedDataSource constructor(
                 HEADER_COMPLETED
             } else if (sortGroup == null) {
                 continue
-            } else if (sortMode == SortHelper.SORT_IMPORTANCE || sortGroup == 0L) {
+            } else if (
+                sortMode == SortHelper.SORT_LIST ||
+                sortMode == SortHelper.SORT_IMPORTANCE ||
+                sortGroup == 0L
+            ) {
                 sortGroup
             } else if (sortMode == SortHelper.SORT_DUE) {
                 when {
@@ -89,6 +93,7 @@ class SectionedDataSource constructor(
                             sections.add(AdapterSection(i, header, 0, isCollapsed))
                         }
                     }
+                    sortMode == SortHelper.SORT_LIST ||
                     sortMode == SortHelper.SORT_IMPORTANCE ->
                         if (header != previous) {
                             sections.add(AdapterSection(i, header, 0, isCollapsed))

app/src/main/java/org/tasks/tasklist/TaskViewHolder.kt

@@ -17,6 +17,7 @@ import com.todoroo.andlib.utility.DateUtilities
 import com.todoroo.andlib.utility.DateUtilities.now
 import com.todoroo.astrid.api.Filter
 import com.todoroo.astrid.core.SortHelper.SORT_DUE
+import com.todoroo.astrid.core.SortHelper.SORT_LIST
 import com.todoroo.astrid.core.SortHelper.SORT_START
 import com.todoroo.astrid.ui.CheckableImageView
 import org.tasks.R
@@ -140,7 +141,7 @@ class TaskViewHolder internal constructor(
         markdown.setMarkdown(nameView, task.title)
         setupTitleAndCheckbox()
         setupDueDate(sortMode == SORT_DUE)
-        setupChips(filter, sortMode == SORT_START)
+        setupChips(filter, sortMode == SORT_START, sortMode == SORT_LIST)
         if (preferences.getBoolean(R.string.p_show_description, true)) {
             markdown.setMarkdown(description, task.notes)
             description.visibility = if (task.hasNotes()) View.VISIBLE else View.GONE
@@ -215,7 +216,7 @@ class TaskViewHolder internal constructor(
         }
     }
 
-    private fun setupChips(filter: Filter, sortByStartDate: Boolean) {
+    private fun setupChips(filter: Filter, sortByStartDate: Boolean, sortByList: Boolean) {
         chipGroup.setContent {
             AppCompatTheme {
                 ChipGroup(
@@ -238,6 +239,7 @@ class TaskViewHolder internal constructor(
                         isSubtask = task.hasParent(),
                         isGoogleTask = task.isGoogleTask,
                         sortByStartDate = sortByStartDate,
+                        sortByList = sortByList,
                         toggleSubtasks = { task: Long, collapsed: Boolean -> callback.toggleSubtasks(task, collapsed) },
                         onClick = { it: Filter -> callback.onClick(it) },
                     )

app/src/main/java/org/tasks/tasklist/ViewHolderFactory.kt

@@ -16,7 +16,7 @@ import org.tasks.preferences.ResourceResolver
 import org.tasks.tasklist.TaskViewHolder.ViewHolderCallbacks
 import org.tasks.ui.CheckBoxProvider
 import org.tasks.ui.ChipProvider
-import java.util.*
+import java.util.Locale
 import javax.inject.Inject
 
 class ViewHolderFactory @Inject constructor(
@@ -25,7 +25,9 @@ class ViewHolderFactory @Inject constructor(
         private val chipProvider: ChipProvider,
         private val checkBoxProvider: CheckBoxProvider,
         private val linkify: Linkify,
-        private val locale: Locale) {
+        private val locale: Locale,
+        private val headerFormatter: HeaderFormatter,
+) {
     private val textColorSecondary: Int = ResourceResolver.getData(context, android.R.attr.textColorSecondary)
     private val textColorOverdue: Int = context.getColor(R.color.overdue)
     private val fontSize: Int = preferences.fontSize
@@ -40,9 +42,10 @@ class ViewHolderFactory @Inject constructor(
     fun newHeaderViewHolder(parent: ViewGroup?, callback: (Long) -> Unit) =
             HeaderViewHolder(
                     context,
-                    locale,
+                    headerFormatter,
                     LayoutInflater.from(context).inflate(R.layout.task_adapter_header, parent, false),
-                    callback)
+                    callback,
+            )
 
     fun newViewHolder(parent: ViewGroup?, callbacks: ViewHolderCallbacks) =
             TaskViewHolder(

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

@@ -97,6 +97,7 @@ class ChipProvider @Inject constructor(
         place: Place?,
         tagsString: String?,
         sortByStartDate: Boolean,
+        sortByList: Boolean,
         list: String?,
         isSubtask: Boolean,
         isGoogleTask: Boolean,
@@ -125,7 +126,7 @@ class ChipProvider @Inject constructor(
             )
         }
 
-        if (!isSubtask && preferences.showListChip && filter !is CaldavFilter) {
+        if (!isSubtask && !sortByList && preferences.showListChip && filter !is CaldavFilter) {
             remember(list, isGoogleTask) {
                 lists
                     .getCaldavList(list)

app/src/main/java/org/tasks/widget/ScrollableViewsFactory.kt

@@ -26,13 +26,14 @@ import org.tasks.date.DateTimeUtils
 import org.tasks.markdown.Markdown
 import org.tasks.preferences.DefaultFilterProvider
 import org.tasks.preferences.Preferences
+import org.tasks.tasklist.HeaderFormatter
 import org.tasks.tasklist.SectionedDataSource
 import org.tasks.tasklist.SectionedDataSource.Companion.HEADER_COMPLETED
 import org.tasks.time.DateTimeUtils.startOfDay
 import org.tasks.ui.CheckBoxProvider
 import timber.log.Timber
 import java.time.format.FormatStyle
-import java.util.*
+import java.util.Locale
 import kotlin.math.max
 
 internal class ScrollableViewsFactory(
@@ -46,7 +47,8 @@ internal class ScrollableViewsFactory(
     private val locale: Locale,
     private val chipProvider: ChipProvider,
     private val localBroadcastManager: LocalBroadcastManager,
-    private val markdown: Markdown
+    private val markdown: Markdown,
+    private val headerFormatter: HeaderFormatter,
 ) : RemoteViewsFactory {
     private val indentPadding: Int
     private var showDueDates = false
@@ -145,13 +147,12 @@ internal class ScrollableViewsFactory(
         val section = tasks.getSection(position)
         val sortGroup = section.value
         val header: String? = if (filter?.supportsSorting() == true) {
-            section.headerString(
+            headerFormatter.headerStringBlocking(
-                    context,
+                value = section.value,
-                    locale,
+                sortMode = sortMode,
-                    sortMode,
+                alwaysDisplayFullDate = showFullDate,
-                    showFullDate,
+                style = FormatStyle.MEDIUM,
-                    FormatStyle.MEDIUM,
+                compact = compact,
-                    compact
             )
         } else {
             null

app/src/main/java/org/tasks/widget/ScrollableWidgetUpdateService.java

@@ -13,6 +13,7 @@ import org.tasks.data.TaskDao;
 import org.tasks.markdown.MarkdownProvider;
 import org.tasks.preferences.DefaultFilterProvider;
 import org.tasks.preferences.Preferences;
+import org.tasks.tasklist.HeaderFormatter;
 import org.tasks.themes.ColorProvider;
 import org.tasks.ui.CheckBoxProvider;
 
@@ -33,6 +34,7 @@ public class ScrollableWidgetUpdateService extends RemoteViewsService {
   @Inject ChipProvider chipProvider;
   @Inject LocalBroadcastManager localBroadcastManager;
   @Inject MarkdownProvider markdownProvider;
+  @Inject HeaderFormatter headerFormatter;
 
   @Override
   public void onStart(Intent intent, int startId) {
@@ -65,6 +67,8 @@ public class ScrollableWidgetUpdateService extends RemoteViewsService {
         locale,
         chipProvider,
         localBroadcastManager,
-        markdownProvider.markdown(false));
+        markdownProvider.markdown(false),
+        headerFormatter
+    );
   }
 }

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

@@ -42,6 +42,7 @@ File %1$s contained %2$s.\n\n
   <string name="SSD_sort_importance">By priority</string>
   <string name="SSD_sort_modified">By last modified</string>
   <string name="sort_created">By creation time</string>
+  <string name="sort_list">By list</string>
   <string name="FLA_search_filter">Matching \'%s\'</string>
   <string name="FLA_new_filter">Create new filter</string>
   <string name="TEA_title_hint">Task name</string>