private void initButtonPanel(PagesWorker pagesWorker){
buttonPanel = new JPanel();
buttonPanel.setLayout(new BoxLayout(buttonPanel, BoxLayout.Y_AXIS));
buttonPanel.setBorder(BorderFactory.createEmptyBorder(0, 10, 10, 10));
pageActionListener = new PagesActionsMediator(pagesWorker);
//move up button
moveUpButton = new JButton();
moveUpButton.setMargin(new Insets(2, 2, 2, 2));
moveUpButton.addActionListener(pageActionListener);