public void actionPerformed(ActionEvent ae) {
				JTextField jt = (JTextField) ae.getSource();
				try {
					int i = -1;
					i = jt.getText().indexOf('%');
					if (i == -1)
						i = Integer.parseInt(jt.getText());
					else
						i = Integer.parseInt(jt.getText().substring(0, i));

					if (i <= 999)
						m_fScale = i / 100D;

					jt.setText((int) (m_fScale * 100) + "%");
					if (m_fScale > 0.1) {
						if (!a_zoomout.isEnabled())
							a_zoomout.setEnabled(true);
					} else
						a_zoomout.setEnabled(false);
					if (m_fScale < 9.99) {
						if (!a_zoomin.isEnabled())
							a_zoomin.setEnabled(true);
					} else
						a_zoomin.setEnabled(false);
					setAppropriateSize();
					// m_GraphPanel.clearBuffer();
					m_GraphPanel.repaint();
					m_GraphPanel.invalidate();
					m_jScrollPane.revalidate();
				} catch (NumberFormatException ne) {
					JOptionPane.showMessageDialog(GUI.this.getParent(),
							"Invalid integer entered for zoom.", "Error", JOptionPane.ERROR_MESSAGE);
					jt.setText((m_fScale * 100) + "%");
				}
			}