Add a setting to choose if we prefer Tasks.org or OpenTasks.

app/src/main/java/com/etesync/syncadapter/App.kt

@@ -277,6 +277,7 @@ class App : Application() {
         val OVERRIDE_PROXY = "overrideProxy"
         val OVERRIDE_PROXY_HOST = "overrideProxyHost"
         val OVERRIDE_PROXY_PORT = "overrideProxyPort"
+        val PREFER_TASKSORG = "preferTasksOrg"
         val FORCE_LANGUAGE = "forceLanguage"
         val CHANGE_NOTIFICATION = "show_change_notification"
 

app/src/main/java/com/etesync/syncadapter/ui/AppSettingsActivity.kt

@@ -43,6 +43,8 @@ class AppSettingsActivity : BaseActivity() {
         internal lateinit var dbHelper: ServiceDB.OpenHelper
         internal lateinit var settings: Settings
 
+        internal lateinit var prefPreferTasksOrg: SwitchPreferenceCompat
+
         internal lateinit var prefResetHints: Preference
         internal lateinit var prefOverrideProxy: SwitchPreferenceCompat
         internal lateinit var prefDistrustSystemCerts: SwitchPreferenceCompat
@@ -86,6 +88,14 @@ class AppSettingsActivity : BaseActivity() {
                 true
             }
 
+            prefPreferTasksOrg = findPreference("prefer_tasksorg") as SwitchPreferenceCompat
+            prefPreferTasksOrg.isChecked = context!!.defaultSharedPreferences.getBoolean(App.PREFER_TASKSORG, false)
+            prefPreferTasksOrg.onPreferenceChangeListener = Preference.OnPreferenceChangeListener { _, newValue ->
+                context!!.defaultSharedPreferences.edit().putBoolean(App.PREFER_TASKSORG, newValue as Boolean).apply()
+                Snackbar.make(view!!, getString(R.string.app_settings_prefer_tasksorg_snack), Snackbar.LENGTH_LONG).show()
+                true
+            }
+
             prefProxyHost = findPreference("proxy_host") as EditTextPreference
             val proxyHost = settings.getString(App.OVERRIDE_PROXY_HOST, App.OVERRIDE_PROXY_HOST_DEFAULT)
             prefProxyHost.text = proxyHost

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

@@ -93,6 +93,11 @@
     <string name="app_settings_reset_hints">Reset hints</string>
     <string name="app_settings_reset_hints_summary">Re-enables hints which have been dismissed previously</string>
     <string name="app_settings_reset_hints_success">All hints will be shown again</string>
+    <string name="app_settings_sync">Sync</string>
+    <string name="app_settings_prefer_tasksorg">Prefer Tasks.org tasks provider</string>
+    <string name="app_settings_prefer_tasksorg_on">Will sync tasks with Tasks.org if available</string>
+    <string name="app_settings_prefer_tasksorg_off">Will sync tasks with OpenTasks if available</string>
+    <string name="app_settings_prefer_tasksorg_snack">You may need to remove and re-add your account for these changes to take effect.</string>
     <string name="app_settings_connection">Connection</string>
     <string name="app_settings_override_proxy">Override proxy settings</string>
     <string name="app_settings_override_proxy_on">Use custom proxy settings</string>

app/src/main/res/xml/settings_app.xml

@@ -26,6 +26,16 @@
 
     </PreferenceCategory>
 
+    <PreferenceCategory android:title="@string/app_settings_sync">
+
+        <SwitchPreferenceCompat
+            android:key="prefer_tasksorg"
+            android:title="@string/app_settings_prefer_tasksorg"
+            android:summaryOn="@string/app_settings_prefer_tasksorg_on"
+            android:summaryOff="@string/app_settings_prefer_tasksorg_off"/>
+
+    </PreferenceCategory>
+
     <PreferenceCategory android:title="@string/app_settings_connection">
 
         <SwitchPreferenceCompat