Retain content of compose view on orientation change

app/src/main/java/ch/dissem/apps/abit/ComposeMessageFragment.kt

@@ -63,6 +63,7 @@ class ComposeMessageFragment : Fragment() {
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
+        retainInstance = true
         arguments?.apply {
             val draft = getSerializable(EXTRA_DRAFT) as Plaintext?
             if (draft != null) {
@@ -266,6 +267,14 @@ class ComposeMessageFragment : Fragment() {
         super.onPause()
     }
 
+    override fun onDestroyView() {
+        identity = sender_input.selectedItem as BitmessageAddress
+        // recipient is set when one is selected
+        subject = subject_input.text?.toString() ?: ""
+        content = body_input.text?.toString() ?: ""
+        super.onDestroyView()
+    }
+
     private fun send() {
         val ctx = activity ?: throw IllegalStateException("Fragment is not attached to an activity")
         if (recipient == null) {