global: made every user action set a project "modified" state that will prevent

the main window from closing instantly

app/undo/undocommand.cpp

@@ -0,0 +1,33 @@
+#include "undocommand.h"
+
+#include "core.h"
+
+UndoCommand::UndoCommand(QUndoCommand *parent) :
+  QUndoCommand(parent)
+{
+}
+
+void UndoCommand::redo()
+{
+  redo_internal();
+
+  modified_ = Core::instance()->IsProjectModified();
+  Core::instance()->SetProjectModified(true);
+}
+
+void UndoCommand::undo()
+{
+  undo_internal();
+
+  Core::instance()->SetProjectModified(modified_);
+}
+
+void UndoCommand::redo_internal()
+{
+  QUndoCommand::redo();
+}
+
+void UndoCommand::undo_internal()
+{
+  QUndoCommand::undo();
+}