provide fallback in case synchronizing around message list fails for some reason

1 files changed, 32 insertions, 27 deletions

diff --git a/src/main/java/de/pixart/messenger/ui/ConversationFragment.java b/src/main/java/de/pixart/messenger/ui/ConversationFragment.java
index 0b399393d..debc7bdd2 100644
--- a/src/main/java/de/pixart/messenger/ui/ConversationFragment.java
+++ b/src/main/java/de/pixart/messenger/ui/ConversationFragment.java
@@ -143,7 +143,7 @@ public class ConversationFragment extends XmppFragment implements EditMessage.Ke
 
     private static final String STATE_LAST_MESSAGE_UUID = "state_last_message_uuid";
 
-    final protected List<Message> messageList = new ArrayList<>();
+    private final List<Message> messageList = new ArrayList<>();
     final private List<Uri> mPendingImageUris = new ArrayList<>();
     private String lastMessageUuid = null;
     public Uri mPendingEditorContent = null;
@@ -239,33 +239,33 @@ public class ConversationFragment extends XmppFragment implements EditMessage.Ke
                                 return;
                             }
                             runOnUiThread(() -> {
-                                final int oldPosition = binding.messagesView.getFirstVisiblePosition();
-                                Message message = null;
-                                int childPos;
-                                for (childPos = 0; childPos + oldPosition < messageList.size(); ++childPos) {
-                                    message = messageList.get(oldPosition + childPos);
-                                    if (message.getType() != Message.TYPE_STATUS) {
-                                        break;
+                                synchronized (messageList) {
+                                    final int oldPosition = binding.messagesView.getFirstVisiblePosition();
+                                    Message message = null;
+                                    int childPos;
+                                    for (childPos = 0; childPos + oldPosition < messageList.size(); ++childPos) {
+                                        message = messageList.get(oldPosition + childPos);
+                                        if (message.getType() != Message.TYPE_STATUS) {
+                                            break;
+                                        }
                                     }
+                                    final String uuid = message != null ? message.getUuid() : null;
+                                    View v = binding.messagesView.getChildAt(childPos);
+                                    final int pxOffset = (v == null) ? 0 : v.getTop();
+                                    ConversationFragment.this.conversation.populateWithMessages(ConversationFragment.this.messageList);
+                                    try {
+                                        updateStatusMessages();
+                                    } catch (IllegalStateException e) {
+                                        Log.d(Config.LOGTAG, "caught illegal state exception while updating status messages");
+                                    }
+                                    messageListAdapter.notifyDataSetChanged();
+                                    int pos = Math.max(getIndexOf(uuid, messageList), 0);
+                                    binding.messagesView.setSelectionFromTop(pos, pxOffset);
+                                    if (messageLoaderToast != null) {
+                                        messageLoaderToast.cancel();
+                                    }
+                                    conversation.messagesLoaded.set(true);
                                 }
-                                final String uuid = message != null ? message.getUuid() : null;
-                                View v = binding.messagesView.getChildAt(childPos);
-                                final int pxOffset = (v == null) ? 0 : v.getTop();
-                                ConversationFragment.this.conversation.populateWithMessages(ConversationFragment.this.messageList);
-                                try {
-                                    updateStatusMessages();
-                                } catch (IllegalStateException e) {
-                                    Log.d(Config.LOGTAG, "caught illegal state exception while updating status messages");
-                                }
-                                messageListAdapter.notifyDataSetChanged();
-                                int pos = Math.max(getIndexOf(uuid, messageList), 0);
-                                binding.messagesView.setSmoothScrollbarEnabled(true);
-                                binding.messagesView.setFastScrollEnabled(false);
-                                binding.messagesView.setSelectionFromTop(pos, pxOffset);
-                                if (messageLoaderToast != null) {
-                                    messageLoaderToast.cancel();
-                                }
-                                conversation.messagesLoaded.set(true);
                             });
                         }
 
@@ -1863,7 +1863,12 @@ public class ConversationFragment extends XmppFragment implements EditMessage.Ke
             if (pos >= 0) {
                 Message message = null;
                 for (int i = pos; i >= 0; --i) {
-                    message = (Message) binding.messagesView.getItemAtPosition(i);
+                    try {
+                        message = (Message) binding.messagesView.getItemAtPosition(i);
+                    } catch (ArrayIndexOutOfBoundsException e) {
+                        //should not happen if we synchronize properly. however if that fails we just gonna try item -1
+                        continue;
+                    }
                     if (message.getType() != Message.TYPE_STATUS) {
                         break;
                     }