Selection model's getSelectedItem() returns old data item after setting new item:
        list = new ListView<Integer>();
        ArrayList<Integer> data1 = new ArrayList<Integer>();
        data1.add(new Integer(1));
        list.setItems(FXCollections.observableList(data1));
        list.getSelectionModel().select(0);
        System.out.println(list.getSelectionModel().getSelectedItem());
        ArrayList<Integer> data2 = new ArrayList<Integer>();
        data2.add(new Integer(2));
        list.setItems(FXCollections.observableList(data2));
        System.out.println(list.getSelectionModel().getSelectedItem());