X-Git-Url: https://git.quassel-irc.org/?a=blobdiff_plain;f=src%2Fuisupport%2Fbufferview.cpp;h=f5db3e29c25b4ee8777fd4c5a333d02cae9bf3d3;hb=082cb8c8eb6db90cbb2166a0098874e76d5c6ad9;hp=f603bf587e66ed7c5d2e897722ee71bb8dcaf461;hpb=a453c963cf1872e14c83adf1d40a31821c166805;p=quassel.git

diff --git a/src/uisupport/bufferview.cpp b/src/uisupport/bufferview.cpp
index f603bf58..f5db3e29 100644
--- a/src/uisupport/bufferview.cpp
+++ b/src/uisupport/bufferview.cpp
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2005-2019 by the Quassel Project                        *
+ *   Copyright (C) 2005-2020 by the Quassel Project                        *
  *   devel@quassel-irc.org                                                 *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -493,14 +493,18 @@ void BufferView::changeBuffer(Direction direction)
             QModelIndex newParent = currentIndex.sibling(currentIndex.row() - 1, 0);
             if (currentIndex.row() == 0)
                 newParent = lastNetIndex;
-            if (model()->hasChildren(newParent))
-                resultingIndex = newParent.model()->index(model()->rowCount(newParent) - 1, 0, newParent);
+            if (model()->hasChildren(newParent)) {
+                // Treat an invalid QAbstractItemModel as an invalid QModelIndex
+                resultingIndex = (newParent.model() ? newParent.model()->index(model()->rowCount(newParent) - 1, 0, newParent) : QModelIndex());
+            }
             else
                 resultingIndex = newParent;
         }
         else {
-            if (model()->hasChildren(currentIndex))
-                resultingIndex = currentIndex.model()->index(0, 0, currentIndex);
+            if (model()->hasChildren(currentIndex)) {
+                // Treat an invalid QAbstractItemModel as an invalid QModelIndex
+                resultingIndex = (currentIndex.model() ? currentIndex.model()->index(0, 0, currentIndex) : QModelIndex());
+            }
             else
                 resultingIndex = currentIndex.sibling(currentIndex.row() + 1, 0);
         }
@@ -509,8 +513,10 @@ void BufferView::changeBuffer(Direction direction)
     if (!resultingIndex.isValid()) {
         if (direction == Forward)
             resultingIndex = model()->index(0, 0, QModelIndex());
-        else
+        else {
+            // Assume model is valid
             resultingIndex = lastNetIndex.model()->index(model()->rowCount(lastNetIndex) - 1, 0, lastNetIndex);
+        }
     }
 
     selectionModel()->setCurrentIndex(resultingIndex, QItemSelectionModel::ClearAndSelect | QItemSelectionModel::Rows);