Fix crash

Author: tgc-dk

src/displayapp/widgets/PopupMessage.cpp

@@ -17,19 +17,20 @@ void PopupMessage::Create() {
   lv_obj_set_style_local_bg_opa(btnPopup, LV_BTN_PART_MAIN, LV_STATE_DEFAULT, LV_OPA_60);
   lv_obj_t* lblMessage = lv_label_create(btnPopup, nullptr);
   lv_label_set_text_static(lblMessage, message);
-  lv_obj_set_hidden(btnPopup, true);
+  lv_obj_set_hidden(btnPopup, isHidden);
 }
 
 void PopupMessage::SetHidden(bool hidden) {
-  NRF_LOG_INFO("PopupMessage::SetHidden - hidden %d, ptr: %p", hidden, btnPopup);
   if (isHidden == hidden) {
     return;
   }
   isHidden = hidden;
+  // create/delete on demand
   if (btnPopup == nullptr && !isHidden) {
     Create();
   } else if (btnPopup != nullptr) {
-    lv_obj_set_hidden(btnPopup, isHidden);
+    lv_obj_del (btnPopup);
+    btnPopup = nullptr;
   }
 }