1.  Command line  Input: Scanner class  Output: System.out.println()  GUI Components  Input: Text Fields, Mouse Clicks  Output: Labels, Dialog Boxes  Comparison: Command line versus GUIs  Command line: Easy to learn, good for debugging  Disadvantages: Inappropriate for production systems

2.  AWT (Abstract Window Toolkit)  Simple components, short learning curve  Operating system calls create components (heavy weight)  Single buffering  SWING  Complex components, lots of features, steep learning curve  Draws components locally (lightweight, consistent cross platform look & feel)  Double buffering for increased responsiveness  Extends AWT, often overriding methods  Note : JavaFX and Androids don’t use Swing for mobile devices

3. Heavyweight Lightweight

5.  JApplet  JPanel  JButton  JLabel  LayoutManager  BorderLayout  BoxLayout  JOptionPane  JTextField  JSlider These could help We’ll definitely use these Parent classes  Component  Container  JComponent  Window  Frame  Applet

6. CREATING A JAPPLETCREATING A JFRAME  Extend; code the init method  Get the content pane  Create Components  Add components to the content pane  If draggable, set title and possibly the icon  Set the size  Override Japplet methods as needed  Instantiate or extend  Get the content pane  Create Components  Add components to the content pane  Set title, possibly icon  Set the size  Set location in window  Set close operation  Set visible

7.  Definition: A sub-panel that holds components  Creating a JPanel  Instantiate (new JPanel())  Create and add components (add(new JButton("X"));  If desired  Set background and foreground colors  Set a border (setBorder method)  Set size, preferred size, minimum size, maximum size  Override the paintComponent method if necessary Note: when overriding paintCompnent, you should call super.paintComponent(g);

8.  Definition: An object that controls how components are drawn in a panel  Manager classes  Flow, Border, Box, Grid, GridBag, Overlay, and others  Default if none specified: Flow  Purpose: Abstracts component positioning so appearance will correctly adapt to different platforms.

9. public class ShowBorder extends JFrame { public static void main(String[] args) { JFrame f = new ShowBorder(); Container c = f.getContentPane(); c.setLayout(new BorderLayout(5,10)); c.add(new JButton("East"), BorderLayout.EAST); c.add(new JButton("West"), BorderLayout.WEST); c.add(new JButton("North"), BorderLayout.NORTH); c.add(new JButton("South"), BorderLayout.SOUTH); c.add(new JButton("Center"), BorderLayout.CENTER); f.setTitle("Show Border Layout"); f.setSize(new Dimension(400, 200)); f.setLocationRelativeTo(null); // Center on screen f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.setVisible(true); } Note: setImageIcon can replace the Java coffee cup

10. public class ShowBox extends JFrame { public static void main(String[] args) { JFrame f = new ShowBox(); Container c = f.getContentPane(); c.setLayout(new BoxLayout(c, BoxLayout.X_AXIS)); c.add(new JButton("First")); c.add(Box.createHorizontalStrut(10)); c.add(new JButton("Second")); c.add(Box.createHorizontalGlue()); c.add(new JButton(“Third")); f.setTitle("Show Box Layout"); f.setSize(new Dimension(400, 75)); f.setLocationRelativeTo(null); // Center on screen f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.setVisible(true); } } Note: Box Layouts can be either horizontal or vertical)

11.  Instantiate: JButton button = new JButton(“Reset");  Background Color: button.setBackground(new Color(0,0x99,0xFF));  Foreground Color: button.setForeground(Color.WHITE);  Border: button.setBorder (BorderFactory.createEtchedBorder(EtchedBorder.RAISED));  Tool tip: button.setToolTipText("This is a tool tip");  Change Font: button.setFont(new Font("Arial", Font.BOLD, 25));  Set size of button: button.setSize(BUTTON_SIZE);  Set preferred size: button.setPreferredSize(BUTTON_SIZE);  Set the minimum size: button.setMinimumSize(BUTTON_SIZE);  Set the maximum size: button.setMaximumSize(BUTTON_SIZE);  Listen for button clicks: button.addActionListener(this); Notes: 1) The setText method can change the button label 2)Buttons can also be created with icons (ImageIcon object) 3)Listener methods respond to user interactions (week 5 slides)

12. label = new JLabel("Points: " + 0); label.setBackground (new Color(0x33, 0x66, 0xcc)); label.setForeground(Color.WHITE); label.setOpaque(true); // The default is false. label.setBorder(BorderFactory.createEtchedBorder (EtchedBorder.RAISED)); label.setPreferredSize(new Dimension(100,30)); To change a label: label:.setText ("Points: " + 20); To get a label’s text: String text = label.getText();

13.  Purposes:  Display messages in a production system  Create dialog boxes for gathering user input  JOptionPane class structure: a group of static methods providing a variety of options  Example:  JOptionPane.showMessageDialog (this, "this is a message for the user");  Note: The first argument of showMessageDialog is a GUI component that the message will always appear on top. A null argument is legal, but then the message could go behind the component.

14. JSlider slider = new JSlider(JSlider.VERTICAL); slider.setPaintLabels(true); slider.setPaintTicks(true); slider.setMajorTickSpacing(10); slider.setMinorTickSpacing(1); slider.addChangeListener ( new ChangeListener() { public void stateChanged (ChangeEvent e) { // *** Insert listener code here ** } }); Note: Horizontal Jsliders are also possible Note: background/foreground color, border, font methods exist

15. JPanel panel = new JPanel(); panel.setLayout(new BoxLayout(panel, BoxLayout.X_AXIS)); JTextField field = new JTextField("Initial data"); field.setPreferredSize(new Dimension(200,30)); field.setMaximumSize(field.getPreferredSize()); JLabel label = new JLabel("Enter Something"); panel.add(label); panel.add(Box.createHorizontalStrut(10)); panel.add(field); field.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { // Add listener logic here } });

16.  JCheckBox, JRadioButton, JTextArea, JComboBox, JScrollBar, JTable, JTree, Many others  All swing components follow the same general principles for instantiating, sizing, setting colors/fonts, adding listeners, etc. as was described on the previous slides