GUI Programming In Java

Slide 1: Because Learning Never Stop! GUI Programming in Java Presented by Thanh Pham thanh.phamhong@niithoasen.com 06/2007 B070038 – NIIT Quang Trung

Slide 2: Contents Basic Concepts 1 AWT and Swing Control Components 2 Layout Manager 3 Event Handling 4 Other References 5

Slide 3: Basic Concepts Basic Concepts GUI? AWT Demos Exercises vs. Swing

Slide 4: GUI?  Graphical User Interface (pronounced \"GOO- ee“).  Presents a user-friendly mechanism for interacting with an application.  Users can learn how to use an app quickly and use it more productively.  Ex: Internet Explorer, MS Word, JCreator…  GUIs are built from GUI components (controls or widgets-window gadget).  A GUI component is an object with which the user interacts via the mouse, the keyboard or another form of input, such as voice recognition.

Slide 5: Abstract Window Toolkit (AWT) vs. Swing Similarities:  Tools provided by Java for developing interactive GUI applications  Provides GUI components that can be used in creating Java applications and applets

Slide 6: Abstract Window Toolkit (AWT) vs. Swing  AWT (Abstract Window Toolkit)  Some AWT components use native code  Platform-dependent  Ensure that the look and feel of an application run on different machines be comparable  Swing  Written entirely using the Java programming language  Platform-independent  Ensures applications deployed across different platforms have the same appearance  Built around a number of APIs that implement various parts of the AWT • Can be used with AWT

Slide 7: Demo MessageBox InputBox Create Frame (AWT) Create Frame (Swing) CenterFrame

Slide 8: Exercises Display two input-boxes that accepts two numbers then shows the result. Accepts three numbers, displays the largest, smallest. (Assume that all input values are valid numbers) Create a simple frame

Slide 9: AWT and Swing Control Components AWT and Swing Control Components Swing Demos Exercises AWT

Slide 10: AWT Control Components An AWT control is a component that enables end users to interact with applications created in Java. All AWT controls in Java are subclasses of the Component class. The Component class provides the add() method to add AWT components to containers, such as an applet or a window.

Slide 11: AWT Control Components TextField TextArea Button List CheckBox Choice Labels

Slide 12: Demo FrameWithControl

Slide 13: Swing Control Components  Swing components contain the Pluggable Look and Feel (PL&F) feature that allows applications to have the same behavior on various platforms.  Identifying the Swing Component Class Hierarchy  The JComponent class is the root of the Swing hierarchy, which is an extension of the AWT container class.  The class hierarchy of the Swing components is categorized into: • Top-level Swing Containers: Acts as a container for placing the intermediate-level and atomic swing components, such as panels, frames, buttons, and check boxes. • Intermediate-level Swing Containers: Placed on the top-level containers and contains atomic components. • Atomic Components: Placed on the intermediate-level swing containers. Atomic components are used to accept input from a user.

Slide 14: Swing Control Components  Using the Top-level Swing Containers  JApplet • The JApplet class is an extension of the AWT applet class. • The Swing components that contain an applet need to extend the JApplet class. • The JApplet() constructor enables you to create a swing applet instance when you create an instance of the JApplet class.  JFrame: • The JFrame class is an extension of the AWT Frame class. • You cannot add components directly to JFrame.

Slide 15: Swing Control Components  Using the Top-level Swing Containers (Cont.)  JDialog • The JDialog class is an extension of the AWT java.awt.Dialog class.  Using the Intermediate Level Swing Containers  JPanel • JPanel class is an extension of the JComponent class that provides a replacement for the AWT Panel class. • You create a panel and add various components to it. • The panel is further added to the content pane, which represents the display area of a window, a dialog, or a frame. • JPanel supports all layout managers of AWT. • By default, JPanel applies the flow layout manager.

Slide 16: Swing Control Components  Using the Intermediate Level Swing Containers (Contd.)  JTabbedPane: • The JTabbedPane class is used to create a tabbed pane component that enables you to switch between groups of components by clicking a tab with a given label. • Tabs are added to the JTabbedPane object by using the addTab() method. • The JTabbedPane class enables you to add multiple components but it displays only a single component at a time.  Using the Atomic Components  JButton  JTextField  JCheckBox  JComboBox  JLabel  JRadioButton

Slide 17: Demo JFrameWithControl

Slide 18: Exercises

Slide 19: Layout Managers Layout Managers Border Grid Demo Flow Layout Layout Layout

Slide 20: Layout Managers  The layout managers are used to position the components, such as an applet, a panel, or a frame in a container.  The layout managers implement the java.awt.LayoutManager interface.  A layout manager is an instance of the LayoutManager interface in Java.  You can use the following method to apply the desired layout to the components:  void setLayout(layoutManager obj)  In the preceding syntax, obj is the reference to the desired layout manager.  Java has various predefined classes of layout managers.  All layout managers make use of the setLayout() method to set the layout of a container.  If the setLayout() method is not used, then the default layout of the container is set.

Slide 21: Layout Managers  The different types of layout managers are:  FlowLayout Manager • The flow layout is the default layout manager used for the Applet class. • In the flow layout manager, the components are placed in a container window in a sequence one after the other in rows. • Java provides the FlowLayout class to apply flow layout to the various components that you are inserting in an applet. • You can use the following constructors to create an instance of the FlowLayout class: – FlowLayout() – FlowLayout(int align) – FlowLayout(int align, int hgap,int vgap)

Slide 22: Layout Managers  BorderLayout Manager  BorderLayout is the default layout of the Frame class.  The BorderLayout layout manager divides the container into north, south, east, west, and centre regions.  You can place five components or controls in each part.  Java provides the BorderLayout class to apply the border layout to the components.  The setLayout() method is used for applying border layout to a container.  You specify the directions for the BorderLayout using the BorderLayout.NORTH, BorderLayout.SOUTH, BorderLayout.EAST, BorderLayout.WEST, and BorderLayout.CENTER constants.  You can use the following constructors to create an instance of the BorderLayout class:  BorderLayout()  BorderLayout(int h, int v)

Slide 23: Layout Managers  GridLayout Manager  The grid layout is the layout that divides the container into rows and columns.  The intersection of a row and a column of the grid layout is called cell.  The GridLayout class of Java enables you to create a grid layout.  All the components in a grid are of the same size.  You can use the following constructors to create an instance of the GridLayout class: • GridLayout() • GridLayout(int r, int c) • GridLayout(int r, int c, int h, int v)

Slide 24: Demo FlowLayout BorderLayout GridLayout

Slide 25: To be continued To be continued….

Slide 26: References Java Passion from Sun Microsystems Java Tutorial from Sun Microsystems Core Java 2 Volume I Fundamentals 7th Edition Java How to Program 6th Edition Java Swing 2nd Edition

Slide 27: www.niit-vn.com www.niit-vn.com/4rum