code cleanup

ui/comboboxex.cpp

@@ -0,0 +1,41 @@
+#include "comboboxex.h"
+
+#include "project/undo.h"
+
+#include <QUndoCommand>
+#include <QWheelEvent>
+
+class ComboBoxExCommand : public QUndoCommand {
+public:
+    ComboBoxExCommand(ComboBoxEx* obj, int old_index, int new_index) :
+        combobox(obj), old_val(old_index), new_val(new_index), done(true) {}
+    void undo() {
+        combobox->setCurrentIndex(old_val);
+        done = false;
+    }
+    void redo() {
+        if (!done) {
+            combobox->setCurrentIndex(new_val);
+        }
+    }
+private:
+    ComboBoxEx* combobox;
+    int old_val;
+    int new_val;
+    bool done;
+};
+
+ComboBoxEx::ComboBoxEx(QWidget *parent) : QComboBox(parent), index(0) {
+    connect(this, SIGNAL(activated(int)), this, SLOT(index_changed(int)));
+}
+
+void ComboBoxEx::index_changed(int i) {
+    if (index != i) {
+        undo_stack.push(new ComboBoxExCommand(this, index, i));
+        index = i;
+    }
+}
+
+void ComboBoxEx::wheelEvent(QWheelEvent* e) {
+    e->ignore();
+}