Editing an item is now undo/redo-able.

model/modelitem.cpp

@@ -16,3 +16,25 @@ bool ModelItem::setData(const QVariant& value, int role) {
 
   return valueChanged;
 }
+
+bool ModelItem::setItemData(const QMap<int, QVariant>& changedValues) {
+  bool valueChanged = false;
+
+  QMap<int, QVariant>::const_iterator citer = changedValues.constBegin();
+
+  while (citer != changedValues.constEnd()) {
+    const int role       = citer.key();
+    const QVariant value = citer.value();
+
+    if (m_values.contains(role)) {
+      if (m_values.value(role) != value) {
+        valueChanged = true;
+      }
+    }
+    m_values[role] = value;
+
+    citer++;
+  }
+
+  return valueChanged;
+}