From f7a38da38365a90bc4dddaf31a63b4e635095c1e Mon Sep 17 00:00:00 2001
From: Mika Fischer <fischer@videmo.de>
Date: Tue, 14 Jun 2011 10:24:16 +0200
Subject: [PATCH] Fix going to next/previous image

---
 sloth/annotations/model.py | 16 ++++++++++++++++
 sloth/core/labeltool.py    | 12 ++++++------
 2 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/sloth/annotations/model.py b/sloth/annotations/model.py
index f120c48..ebce7eb 100644
--- a/sloth/annotations/model.py
+++ b/sloth/annotations/model.py
@@ -34,6 +34,22 @@ class ModelItem(QObject):
         assert self.parent_ is None
         self.parent_ = parent
 
+    def getPreviousSibling(self):
+        if self.parent_ is not None:
+            c = self.parent().children()
+            row = c.index(self)
+            if row > 0:
+                return c[row-1]
+        return None
+
+    def getNextSibling(self):
+        if self.parent_ is not None:
+            c = self.parent().children()
+            row = c.index(self)
+            if row < len(c) - 2:
+                return c[row+1]
+        return None
+
     def setIndex(self, index):
         assert self._pindex is None
         self._pindex = QPersistentModelIndex(index)
diff --git a/sloth/core/labeltool.py b/sloth/core/labeltool.py
index 763a854..8c5415c 100755
--- a/sloth/core/labeltool.py
+++ b/sloth/core/labeltool.py
@@ -139,15 +139,15 @@ class LabelTool(QObject):
 
     def gotoNext(self):
         # TODO move this to the scene
-        if self._model is not None and self.current_index_ is not None:
-            next_index = self._model.getNextIndex(self.current_index_)
-            self.setCurrentIndex(next_index)
+        if self._model is not None and self._current_image is not None:
+            next_image = self._current_image.getNextSibling()
+            self.setCurrentImage(next_image)
 
     def gotoPrevious(self):
         # TODO move this to the scene
-        if self._model is not None and self.current_index_ is not None:
-            prev_index = self._model.getPreviousIndex(self.current_index_)
-            self.setCurrentIndex(prev_index)
+        if self._model is not None and self._current_image is not None:
+            prev_image = self._current_image.getPreviousSibling()
+            self.setCurrentImage(prev_image)
 
     def updateModified(self):
         """update all GUI elements which depend on the state of the model,