Fix deprecations

app/src/main/java/org/tasks/preferences/fragments/Backups.kt

@@ -52,7 +52,7 @@ class Backups : InjectingPreferenceFragment() {
         findPreference(R.string.backup_BAc_export)
             .setOnPreferenceClickListener {
                 ExportTasksDialog.newExportTasksDialog()
-                    .show(fragmentManager!!, FRAG_TAG_EXPORT_TASKS)
+                    .show(parentFragmentManager, FRAG_TAG_EXPORT_TASKS)
                 false
             }
 
@@ -135,7 +135,7 @@ class Backups : InjectingPreferenceFragment() {
                     toaster.longToast(R.string.invalid_backup_file)
                 } else {
                     ImportTasksDialog.newImportTasksDialog(uri, extension)
-                        .show(fragmentManager!!, FRAG_TAG_IMPORT_TASKS)
+                        .show(parentFragmentManager, FRAG_TAG_IMPORT_TASKS)
                 }
             }
         } else if (requestCode == REQUEST_DRIVE_BACKUP) {

app/src/main/java/org/tasks/preferences/fragments/LookAndFeel.kt

@@ -106,7 +106,7 @@ class LookAndFeel : InjectingPreferenceFragment(), Preference.OnPreferenceChange
         languagePreference.onPreferenceClickListener = Preference.OnPreferenceClickListener {
             val dialog = LocalePickerDialog.newLocalePickerDialog()
             dialog.setTargetFragment(this, REQUEST_LOCALE)
-            dialog.show(fragmentManager!!, FRAG_TAG_LOCALE_PICKER)
+            dialog.show(parentFragmentManager, FRAG_TAG_LOCALE_PICKER)
             false
         }
 

app/src/main/java/org/tasks/preferences/fragments/TaskDefaults.kt

@@ -54,7 +54,7 @@ class TaskDefaults : InjectingPreferenceFragment() {
                     this,
                     REQUEST_REMOTE_LIST
                 )
-                    .show(fragmentManager!!, FRAG_TAG_REMOTE_LIST_SELECTION)
+                    .show(parentFragmentManager, FRAG_TAG_REMOTE_LIST_SELECTION)
                 false
             }
         updateRemoteListSummary()