1 / 16

GUI Programming I

22. GUI Programming I. Previously. Threads Thread class Runnable interface Priority. Overview. Hello World as GUI Layout Design Criteria In GUI Human Interface Concepts Requirements Use Cases Design GUI Java Foundation Classes. Hello World as GUI. import javax.swing.JFrame ;

bryce
Download Presentation

GUI Programming I

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 22 GUI Programming I

  2. Previously • Threads • Thread class • Runnable interface • Priority

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

  4. Hello World as GUI importjavax.swing.JFrame; importjavax.swing.JLabel; public class HelloWorldGUIextendsJFrame { public static void main(String[] args) { newHelloWorldGUI(); } // main() HelloWorldGUI() { super("Hello World"); // the title JLabeljlbHelloWorld = newJLabel(" 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

  5. Layout Design • Layout design concerns with the presentation of information in a clear and concise manner • Users should be able to process presented information with little effort • Use already in use layout or similar Minimize GUI Title Maximize GUI Logo of the application Exit GUI Application GUI data area

  6. Criteria In GUI • All data is presented in the minimum amount of space without been cluttered or disorganized • User been able to locate desired information quickly • Scale to fit more or less data

  7. Human Interface Concepts • Organize the user’s flow of events when attempting to complete a task • Human interface decisions determine how users interact with the system • Abstracting the actual functions of the system away from the user • Approach the application from the point of view of the user

  8. Requirements • Reread the requirements for the application • Look for certain interaction information • Who are the primary users of the system? • What do users employ the system for? • What tasks must it allow the users to execute? • What actions are required by the system in order to complete these tasks? • These means to create a set of simple use cases

  9. Use Cases • Use cases spell out • How all the actors interact with the system • What the system will allow the actors to execute • Specify steps required to complete a task Add record View record Edit record Save record Delete record Database User actor actor

  10. Use Cases • Fill in the details of each action • Break the steps further into sub-steps • Add extra information, i.e. requirement to proceed with the step • Plan interface that requires the minimum number of steps for user to complete task

  11. Sample • Possible sub-steps to shown Use Cases • To Add a record first one has to be created and filled – maybe using the same code than Edit. Should we add a new action "New“ or called New instead of Add • To View records they have to exist and be selected. • What happens if no records exist? • To Edit a record the record has to exist and must be selected • To Save a record the record has to exist, has to be selected and should have been changed • To Delete a record the record has to exist and has to be selected before deleting it

  12. Design GUI • Use components commonly used, e.g. menu bar with menu items, popup menus, fast keys,... • Improve usability • Speed the learning process for users of your application • Reduce implementation; most of the time they are well defined and there are available with plenty of examples • Minimise steps to complete operation • Do not compromise usability

  13. Model-View-Controller Pattern • MRV main propose is to separate responsibilities for the various tasks involved in the user interface (UI) • Responsibilities • Interface to the system • Display of the data to the end user • Accepting input from the user, parsing and processing it • Allows to change the UI rapidly file system Process data GUI

  14. Java Foundation Classes • JFC stands for Java Foundation Classes • An extension to the original Abstract Window Toolkit (AWT) contained in java.awt and sub-packages • Includes swing • Pluggable look and feel designs • Java Accessibility API • All implemented without native code • Code that refers to the functions of a specific operating system or is compiled for a specific processor

  15. Java Foundation Classes • Pluggable Look-and-Feel Support void UIManager.setLookAndFeel(String nameOfLookAndFeel) String UIManager.getSystemLookAndFeelClassName() • Already some of them provided com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel com.sun.java.swing.plaf.metal.MetalLookAndFeel • You can add you own ones NimbusLookAndFeel

  16. Swing • Part of the Java SE platform • Provides a rich set of GUI component, also called controls • Some controls offer sophisticated functionality • Text fields provide formatted text input or password field behaviour • You can increase their functionality by creating your own from an existing one • Package for controls is javax.swing

More Related