Fixes FS#81 - avoid jumps after loading messages

1 files changed, 32 insertions, 22 deletions

diff --git a/src/main/java/de/thedevstack/conversationsplus/services/XmppConnectionService.java b/src/main/java/de/thedevstack/conversationsplus/services/XmppConnectionService.java
index 8ff5f0d2..5e529f3c 100644
--- a/src/main/java/de/thedevstack/conversationsplus/services/XmppConnectionService.java
+++ b/src/main/java/de/thedevstack/conversationsplus/services/XmppConnectionService.java
@@ -1050,32 +1050,38 @@ public class XmppConnectionService extends Service implements OnPhoneContactsLoa
             Log.d("mam", "Query in progress");
 			return;
 		}
+        //TODO Create a separate class for this runnable to store if messages are getting loaded or not. Not really a good idea to do this in the callback.
 		Runnable runnable = new Runnable() {
 			@Override
 			public void run() {
-				final Account account = conversation.getAccount();
-				List<Message> messages = databaseBackend.getMessages(conversation, 50,timestamp);
-                Log.d("mam", "runnable load more messages");
-				if (messages.size() > 0) {
-                    Log.d("mam", "At least one message");
-					conversation.addAll(0, messages);
-					checkDeletedFiles(conversation);
-					callback.onMoreMessagesLoaded(messages.size(), conversation);
-				} else if (conversation.hasMessagesLeftOnServer()
-						&& account.isOnlineAndConnected()
-						&& account.getXmppConnection().getFeatures().mam()) {
-                    Log.d("mam", "mam activate, account online and connected and messages left on server");
-					MessageArchiveService.Query query = getMessageArchiveService().query(conversation,0,timestamp - 1);
-					if (query != null) {
-						query.setCallback(callback);
-					}
-					callback.informUser(R.string.fetching_history_from_server);
-				} else {
-                    Log.d("mam", ((!conversation.hasMessagesLeftOnServer()) ? "no" : "") + " more messages left on server, mam " + ((account.getXmppConnection().getFeatures().mam()) ? "" : "not") + " activated, account is " + ((account.isOnlineAndConnected()) ? "" : "not") + " online or connected)");
-                    callback.onMoreMessagesLoaded(0, conversation);
-                    callback.informUser(R.string.no_more_history_on_server);
+                if (null == callback || !callback.isLoadingInProgress()) { // if a callback is set, ensure that there is no loading in progress
+                    if (null != callback) {
+                        callback.setLoadingInProgress(); // Tell the callback that the loading is in progress
+                    }
+                    final Account account = conversation.getAccount();
+                    List<Message> messages = databaseBackend.getMessages(conversation, 50, timestamp);
+                    Log.d("mam", "runnable load more messages");
+                    if (messages.size() > 0) {
+                        Log.d("mam", "At least one message");
+                        conversation.addAll(0, messages);
+                        checkDeletedFiles(conversation);
+                        callback.onMoreMessagesLoaded(messages.size(), conversation);
+                    } else if (conversation.hasMessagesLeftOnServer()
+                            && account.isOnlineAndConnected()
+                            && account.getXmppConnection().getFeatures().mam()) {
+                        Log.d("mam", "mam activate, account online and connected and messages left on server");
+                        MessageArchiveService.Query query = getMessageArchiveService().query(conversation, 0, timestamp - 1);
+                        if (query != null) {
+                            query.setCallback(callback);
+                        }
+                        callback.informUser(R.string.fetching_history_from_server);
+                    } else {
+                        Log.d("mam", ((!conversation.hasMessagesLeftOnServer()) ? "no" : "") + " more messages left on server, mam " + ((account.getXmppConnection().getFeatures().mam()) ? "" : "not") + " activated, account is " + ((account.isOnlineAndConnected()) ? "" : "not") + " online or connected)");
+                        callback.onMoreMessagesLoaded(0, conversation);
+                        callback.informUser(R.string.no_more_history_on_server);
+                    }
                 }
-			}
+            }
 		};
 		mDatabaseExecutor.execute(runnable);
 	}
@@ -2553,6 +2559,10 @@ public class XmppConnectionService extends Service implements OnPhoneContactsLoa
 		public void onMoreMessagesLoaded(int count, Conversation conversation);
 
 		public void informUser(int r);
+
+        void setLoadingInProgress();
+
+        boolean isLoadingInProgress();
 	}
 
 	public interface OnAccountPasswordChanged {