Outline 0024 Spring 2010 17 :: 2 More information about Swing - PowerPoint PPT Presentation

Outline �� 0024 Spring 2010 � – 17 :: 2 – �

More information about Swing 
 0024 Spring 2010 � – 17 :: 3 – �

Java Foundation Classes � import java.awt.*; import java.awt.event.*; � import javax.swing.*; import javax.swing.event.*; � 0024 Spring 2010 � – 17 :: 4 – �

Swing vs. AWT � 0024 Spring 2010 � – 17 :: 5 – � (c) O ʼ Reilly 1999 �

Swing � 0024 Spring 2010 � – 17 :: 6 – �

Top-level containers � 0024 Spring 2010 � – 17 :: 7 – � http://java.sun.com/docs/books/tutorial/ui/features/components.html �

Containers � containers � 0024 Spring 2010 � – 17 :: 8 – �

General-purpose containers � 0024 Spring 2010 � – 17 :: 9 – �

Basic controls � 0024 Spring 2010 � – 17 :: 10 – �

Essential Swing components � AWT � Swing � 0024 Spring 2010 � – 17 :: 11 – �

Example 1 � pack() causes a window to be sized to fit the preferred size and layouts of its sub- components � 0024 Spring 2010 � – 17 :: 12 – �

Example 2 � In this example how a custom frame is created � 0024 Spring 2010 � – 17 :: 13 – �

Build from bottom up � JButton � JLabel � JPanel � JFrame � 0024 Spring 2010 � – 17 :: 14 – �

Layout managers � Organizing Layout of components in a container � FlowLayout � GridLayout � null � none, 
 Left to right, � programmer 
 Top to bottom � sets x,y,w,h � GridBagLayout � BorderLayout � CardLayout � n � w � e � JButton � c � One at a time � s � 0024 Spring 2010 � – 17 :: 15 – �

Combinations � JButton � JButton � JTextArea � 0024 Spring 2010 � – 17 :: 16 – �

Combinations � JButton � JButton � JFrame � n � JPanel: FlowLayout � JPanel: BorderLayout � c � JTextArea � 0024 Spring 2010 � – 17 :: 17 – �

Code: null layout � press me 0024 Spring 2010 � – 17 :: 18 – �

Code: FlowLayout � press me then me 0024 Spring 2010 � – 17 :: 19 – �

import java.awt.*; import javax.swing.*; public class Main { public static void main(String[] args) { JFrame f = new JFrame("title"); JPanel p = new JPanel( ); FlowLayout L = new FlowLayout( ); JButton b1 = new JButton("press me"); JButton b2 = new JButton("then me"); p.setLayout(L); p.add(b1); p.add(b2); f.setContentPane(p); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.pack(); f.setVisible( true ); } } 0024 Spring 2010 � – 17 :: 20 – �

Box Layout � myPane.setLayout(new BoxLayout(myPane, BoxLayout.PAGE_AXIS)); � Component.CENTER_ALIGNMENT � Component.RIGHT_ALIGNMENT � Component.LEFT_ALIGNMENT � 0024 Spring 2010 � – 17 :: 21 – �

A simple Swing program - Events • Objects communicate by “firing” and “handling” events � • Events are sent from a single source object to one or more registered listener objects � 0024 Spring 2010 � – 17 :: 22 – �

Types of event listeners � Act that results in event Listener type ActionListener User clicks a button, presses Return while typing in a text field, or chooses a menu item User closes a frame (main window) WindowListener User presses a mouse button while the cursor is over MouseListener a component User moves the mouse over a component MouseMotionListener Component becomes visible ComponentListener Component gets the keyboard focus FocusListener Table or list selection changes ListSelectionListener 0024 Spring 2010 � – 17 :: 23 – �

Handling events I � Listener � JButton � JLabel � JPanel � JFrame � 0024 Spring 2010 � – 17 :: 24 – �

Event handling II � 0024 Spring 2010 � – 17 :: 25 – �

Example using local class � 0024 Spring 2010 � – 17 :: 26 – �

JDialog � 0024 Spring 2010 � – 17 :: 27 – �

Dialog Example � The JOptionPane class can be used to create simple modal dialogs (icons, title, text and buttons can be customized). � 0024 Spring 2010 � – 17 :: 28 – �

Swing and Threads � 0024 Spring 2010 � – 17 :: 29 – �

Safe Swing code � Unsafe to update state of Swing components Safe to update state of Swing components 0024 Spring 2010 � – 17 :: 30 – �

Event Dispatching � javax.swing.SwingUtilities.invokeLater( new Runnable(){ public void run(){ // Access to components } } ); 0024 Spring 2010 � – 17 :: 31 – �

Handle a job in the background � 0024 Spring 2010 � – 17 :: 32 – �

Model/View/Controller [MVC] � http://www.itu.dk/courses/VOP/E2005/VOP2005E/8_mvc_krasner_and_pope.pdf � 0024 Spring 2010 � – 17 :: 33 – �

Model/View/Controller �  Model �  complete, self-contained representation of object managed by the application 
 e.g., spreadsheet document �  provides a number of services to manipulate the data 
 e.g., recalculate, save �  computation and persistence issues �  Try to separate the model and its services so that it is Swing-free � 0024 Spring 2010 � – 17 :: 34 – �

Model/View/Controller �  View �  tracks what is needed for a particular perspective of the data 
 e.g., bar chart view �  presentation issues �  Controller �  gets input from the user, and uses appropriate information from the view to modify the model 
 e.g., get slider value, trigger chart modify �  interaction issues �  In practice, views and controllers are implemented with Swing components and listeners � 0024 Spring 2010 � – 17 :: 35 – �

Model/View/Controller � 0024 Spring 2010 � – 17 :: 36 – �

MVC � 0024 Spring 2010 � – 17 :: 37 – �

Pluggable “Look and Feel” � 0024 Spring 2010 � – 17 :: 38 – �

Pluggable Look-and-Feel � http://java.sun.com/docs/books/tutorial/ui/overview/demo.html � 0024 Spring 2010 � – 17 :: 39 – �

Extra part � 0024 Spring 2010 � – 17 :: 40 – �

Applets � JApplet � contentPane � JButton � 0024 Spring 2010 � – 17 :: 41 – �

Applet Methods � 0024 Spring 2010 � – 17 :: 42 – �

Application + Applet � Command line � Browser � or � JFrame � JApplet � contentPane � JPanel � JButton � 0024 Spring 2010 � – 17 :: 43 – �

Applet Security � 0024 Spring 2010 � – 17 :: 44 – �

Java 2D API � 0024 Spring 2010 � – 17 :: 45 – �

Graphics � JButton � 0024 Spring 2010 � – 17 :: 46 – �

Coordinate System � (0,0) (width,0) (0,height) (width, height) 0024 Spring 2010 � – 17 :: 47 – �

Painting Components � JButton � JPanel � 0024 Spring 2010 � – 17 :: 48 – �

Painting in Java � 0024 Spring 2010 � – 17 :: 49 – �

Graphics Primitives � http://java.sun.com/docs/books/tutorial/2d/geometry/primitives.html � label 0024 Spring 2010 � – 17 :: 50 – �

Graphics Attributes � 0024 Spring 2010 � – 17 :: 51 – �

Code � Hello World � To paint the inside of a component, 
 override the paintComponent � 0024 Spring 2010 � – 17 :: 52 – �

Creating and Drawing to an Image � http://java.sun.com/docs/books/tutorial/2d/images/drawonimage.html � 0024 Spring 2010 � – 17 :: 53 – �

Reading/Loading Image � 0024 Spring 2010 � – 17 :: 54 – �

How to proceed … � 0024 Spring 2010 � – 17 :: 55 – �