create interface for onBackendConnected

1 files changed, 4 insertions, 2 deletions

diff --git a/src/main/java/de/pixart/messenger/utils/UIHelper.java b/src/main/java/de/pixart/messenger/utils/UIHelper.java
index 92efe4d26..13a08aedd 100644
--- a/src/main/java/de/pixart/messenger/utils/UIHelper.java
+++ b/src/main/java/de/pixart/messenger/utils/UIHelper.java
@@ -419,12 +419,14 @@ public class UIHelper {
     public static String concatNames(List<MucOptions.User> users, int max) {
         StringBuilder builder = new StringBuilder();
         final boolean shortNames = users.size() >= 3;
-        for (int i = 0; i < Math.max(users.size(), max); ++i) {
+        for (int i = 0; i < Math.min(users.size(), max); ++i) {
             if (builder.length() != 0) {
                 builder.append(", ");
             }
             final String name = UIHelper.getDisplayName(users.get(i));
-            builder.append(shortNames ? name.split("\\s+")[0] : name);
+            if (name != null) {
+                builder.append(shortNames ? name.split("\\s+")[0] : name);
+            }
         }
         return builder.toString();
     }