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G54PRG ProgrammingLecture

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Amadeo Ascó Adam Moore

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GUI Programming II: Components

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Previously

• Hello World as GUI• Layout Design• Criteria In GUI• Human Interface Concepts• Requirements• Use Cases• Design GUI• Java Foundation Classes

Add record

View record

Edit record

Save record

Delete recordactorUser Database

actor

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Overview

• Hierarchy• Overview Swing Components• Swing Components

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HierarchyObject

Component

Container

JLabel

JButton

JMenuBar

JPanel JTable

JCheckBoxJComboBoxJTextField

JTextArea

JComponent

java.awt

javax.swing

Abstract Window Toolkit (AWT)

java.lang

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Swing Components• Position Layout Managers• Look how the control is displayed on the

screen• Feel - base functionality

– Do you click on them. e.g. button (JButton)– Do you type on them, e.g. text field (JTextField) ...

• Functionality Events– What happen when the corresponding action has

been executed by the user, e.g. clicking on the "Save" button save the data

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• JPanel

• JScrollBar

• JSlider

• JSplitPane

• JButton

• JCheckBox

• JComboBox

• JRadioButton

• JPopupMenu

Overview Swing Components

Divider between panels can be drag left and right

Divider between panels can be drag left and right

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• JMenuBar

• JMenu • JMenuItem• JTextField• JTabbedPane• JTextArea

• JTree

• JLabel Fix text on the display

• JDialog• JTabel

Swing ComponentsSubSuperClasses

src

docreadme.txtjavadoc

bin

Tab 1 Tab 2 Tab 3

Application title

Panel

Data was saved.

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Swing Componentsimport javax.swing.JFrame;import javax.swing.JLabel;

public class HelloWorldGUI extends JFrame { public static void main(String[] args) { new HelloWorldGUI(); } // main()

HelloWorldGUI() { super("Hello World"); // the title JLabel jlbHelloWorld = new JLabel(" Hello World!");

add(jlbHelloWorld); // add label to the GUI setSize(150, 80); // size of the window setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setVisible(true); // show the GUI } // Constructor ()} // end class HelloWorldGUI

import javax.swing.JFrame;import javax.swing.JLabel;

public class HelloWorldGUI extends JFrame { public static void main(String[] args) { new HelloWorldGUI(); } // main()

HelloWorldGUI() { super("Hello World"); // the title JLabel jlbHelloWorld = new JLabel(" Hello World!");

add(jlbHelloWorld); // add label to the GUI setSize(150, 80); // size of the window setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setVisible(true); // show the GUI } // Constructor ()} // end class HelloWorldGUI

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public class HelloWorldGUI extends JFrame { ...

HelloWorldGUI() { super("Hello World"); // the title JLabel jlbHelloWorld = new JLabel(" Hello World!");

add(jlbHelloWorld); // add label to the GUI setSize(150, 80); // size of the window setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setVisible(true); // show the GUI } // Constructor ()} // end class HelloWorldGUI

public class HelloWorldGUI extends JFrame { ...

HelloWorldGUI() { super("Hello World"); // the title JLabel jlbHelloWorld = new JLabel(" Hello World!");

add(jlbHelloWorld); // add label to the GUI setSize(150, 80); // size of the window setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setVisible(true); // show the GUI } // Constructor ()} // end class HelloWorldGUI

Swing Components

• Extend JFrame to get the general look of a GUI• JLabel corresponds to fix text to add to the GUI

Hello World

width

he

igh

t

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Swing Components• Creating and Showing Simple Dialogs

– It is a accomplished by using the class JDialog– Different ones depending of the message to display– Default title and icon

JOptionPane.showMessageDialog(frame, "Data was saved.", "Message");

– Custom title, warning iconJOptionPane.showMessageDialog(frame,“Data was saved.", "Warning!", JOptionPane.WARNING_MESSAGE);

– Custom title, error iconJOptionPane.showMessageDialog(frame,"Data wasn’t saved.", “Error!", JOptionPane.ERROR_MESSAGE);

Data was saved.

Data was saved.

Warning!

Data wasn’t saved.

Error!

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Swing Components

• Yes/No dialog with default icon, custom titleint iAnswer = JOptionPane.showConfirmDialog(frame, "Would you like to

save the data?", "Question!", JOptionPane.YES_NO_OPTION);

Valid return values• JOptionPane.YES_OPTION: user has selected 'YES'• JOptionPane.NO_OPTION: user has selected 'NO'• JOptionPane.CLOSED_OPTION: user closed the dialog window

explicitly, rather than by choosing a button inside the option pane

Would you like to save the data?

Question!

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Swing Components• JMenuBar and JMenuItem//Create the menu barJMenuBar menuBar = new JMenuBar();

//Build the first menuJMenu menu = new JMenu("1st Menu");

menuBar.add(menu); // add menu to menu bar

// Add menu itemsJMenuItem menuItem = new JMenuItem("1st Option");

menuItem.addItemListener(this); // register the listenermenu.add(menuItem); // add item to a container

menuItem = new JMenuItem("2nd Option");menuItem.addItemListener(this); // register the listenermenu.add(menuItem); // add item to a container...jFrame.setJMenuBar(menuBar); // set menu bar

//Create the menu barJMenuBar menuBar = new JMenuBar();

//Build the first menuJMenu menu = new JMenu("1st Menu");

menuBar.add(menu); // add menu to menu bar

// Add menu itemsJMenuItem menuItem = new JMenuItem("1st Option");

menuItem.addItemListener(this); // register the listenermenu.add(menuItem); // add item to a container

menuItem = new JMenuItem("2nd Option");menuItem.addItemListener(this); // register the listenermenu.add(menuItem); // add item to a container...jFrame.setJMenuBar(menuBar); // set menu bar

JMenuBaradd(JMenu)

JMenuadd(JMenuItem)add(JMenu)

JMenuItemaddItemListener(ItemListener)

JFramesetJMenuBar(JMenuBar)

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Swing Components

• JTextField

• JButton

JTextField jText = new JTextField(15);...

add(jText); // add to a container...jText.getText(); // get text on the text fields

JTextField jText = new JTextField(15);...

add(jText); // add to a container...jText.getText(); // get text on the text fields

JButton jButton = new JButton("OK");

jButton.setActionCommand ("OK"); // assign an action identifierjButton.addActionListerner(this); // register the listeneradd(jButton); // add to a container...

JButton jButton = new JButton("OK");

jButton.setActionCommand ("OK"); // assign an action identifierjButton.addActionListerner(this); // register the listeneradd(jButton); // add to a container...

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Swing Components

• JTable// HeaderString[] astrColumnNames = {"First name", "Last name", "Num", "Road", "Alive"};Object[][] aoRows = { {"Debby", "Smith", new Integer(5), "Parliament", new Boolean(false)}, {"John", "Rainbow", new Integer(3), "Great Av.", new Boolean(true)}, {"Jason", "Wood", new Integer(2), "Lower line", new Boolean(false)}, {"Jane", "White", new Integer(13), "High Street", new Boolean(true)} };

// Build table using these roes and column namesJTable table = new JTable(aoRows, astrColumnNames);

// HeaderString[] astrColumnNames = {"First name", "Last name", "Num", "Road", "Alive"};Object[][] aoRows = { {"Debby", "Smith", new Integer(5), "Parliament", new Boolean(false)}, {"John", "Rainbow", new Integer(3), "Great Av.", new Boolean(true)}, {"Jason", "Wood", new Integer(2), "Lower line", new Boolean(false)}, {"Jane", "White", new Integer(13), "High Street", new Boolean(true)} };

// Build table using these roes and column namesJTable table = new JTable(aoRows, astrColumnNames);

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ReferencesA Brief Introduction to the Swing Package

http://download.oracle.com/javase/tutorial/ui/overview/index.html

Using Swing Componentshttp://download.oracle.com/javase/tutorial/uiswing/components/

index.html

Java APIhttp://download.oracle.com/javase/6/docs/api/

Course Resources Websitehttp://workspace.nottingham.ac.uk/display/G54ICP/Resources

Java look and feel Graphics Repositoryhttp://java.sun.com/developer/techDocs/hi/repository/