![JOptionPane Methods
• static void showMessageDialog(Component, Object)
• static void showMessageDialog(Component, Object, String, int)
• static void showMessageDialog(Component, Object, String, int, Icon)
• static int showOptionDialog(Component, Object, String, int, int, Icon, Object[], Object)
• static int showConfirmDialog(Component, Object)
• static int showConfirmDialog(Component, Object, String, int)
• static int showConfirmDialog(Component, Object, String, int, int)
• static int showConfirmDialog(Component, Object, String, int, int, Icon)
• static String showInputDialog(Object)
• static String showInputDialog(Component, Object)
• static String showInputDialog(Component, Object, String, int)
• static String showInputDialog(Component, Object, String, int, Icon, Object[], Object)
Instructor: Tanzila Kehkashan
6](https://image.slidesharecdn.com/ooplecture5-inheritancedialogboxesparsing-230115044329-af0548a6/85/OOP-Lecture-5-Inheritance-Dialogboxes-Parsing-pptx-6-320.jpg)
OOP Lecture 5-Inheritance,Dialogboxes,Parsing.pptx
- 1. CS3135/CS2135 Object Oriented Programming (Java) BSCS-3 / MCS-3 Lecture # 5 Inheritance Dialog boxes Parsing
- 2. INHERITANCE • Inheritance is the reusability of predefined functionality. • Existing class is called superclass (base class in C++)and new class is called subclass (derived class in C++). • Inheritance is also called Specialization because subclass can modify the behavior of its superclass appropriately to that subclass. • Direct superclass is the superclass from which subclass explicitly inherits. • Indirect superclass is any class above the direct superclass in class hierarchy. • In Java, class hierarchy begins with class Object (in package java.lang), which every class in Java directly or indirectly extends. • Java supports only single inheritance, in which each class is derived from exactly one direct superclass. It does not support multiple inheritance. Instructor: Tanzila Kehkashan 2
- 3. INHERITANCE A superclass’s • Public members are accessible wherever the program has reference to an object of that superclass or one of its superclass. • Private members can be accessed directly only within the superclass’s declaration. • Protected members have an inheritance level of protection between public and private access. They can be accessed by members of superclass and subclass and other classes in same package. • A superclass’s private methods are hidden in its subclass and can be accessed only through the public or protected methods inherited from the superclass. Relationship between superclass & subclass • A subclass can invoke a constructor of its superclass by using the keyword super followed by a set of parentheses containing the superclass constructor arguments. This must appear as the first statement in the subclass’s constructor body. Example public class person { } public class student extends person { } public class employee extends person { } public class result extends student { } Instructor: Tanzila Kehkashan 3
- 4. GUI Components • GUI component is an object with which the user interacts via mouse, keyboard or another form of input, such as voice recognition. • These are sometimes called controls or widgets (window gadgets). • Lightweight Vs. Heavyweight GUI components • Swing Vs. AWT components • There are two sets of Java GUI components: • ‘java.awt’ package (Abstract Window Toolkit) • ‘javax.swing’ package Instructor: Tanzila Kehkashan 4
- 5. GUI Components -> Dialogue Boxes • Simple GUI based I/O with JOptionPane • import javax.swing.JOptionPane; • Message dialog • Input dialog • Option dialog • Confirm dialog • Dialog Constants / message Type • ERROR_MESSAGE • INFORMATION_MESSAGE • WARNING_MESSAGE • QUESTION_MESSAGE • PLAIN_MESSAGE Instructor: Tanzila Kehkashan 5
- 6. JOptionPane Methods • static void showMessageDialog(Component, Object) • static void showMessageDialog(Component, Object, String, int) • static void showMessageDialog(Component, Object, String, int, Icon) • static int showOptionDialog(Component, Object, String, int, int, Icon, Object[], Object) • static int showConfirmDialog(Component, Object) • static int showConfirmDialog(Component, Object, String, int) • static int showConfirmDialog(Component, Object, String, int, int) • static int showConfirmDialog(Component, Object, String, int, int, Icon) • static String showInputDialog(Object) • static String showInputDialog(Component, Object) • static String showInputDialog(Component, Object, String, int) • static String showInputDialog(Component, Object, String, int, Icon, Object[], Object) Instructor: Tanzila Kehkashan 6
- 7. GUI Components -> Option Type • DEFAULT_OPTION • YES_NO_OPTION • YES_NO_CANCEL_OPTION • OK_CANCEL_OPTION Return Values • YES_OPTION • NO_OPTION • CANCEL_OPTION • OK_OPTION • CLOSED_OPTION GUI Components -> Dialogue Box Constants Instructor: Tanzila Kehkashan 7
- 8. Parse methods convert strings to numeric data types. These are • Byte.parseByte(String) • Integer.parseInt(String) • Short.parseShort(String) • Long.parseLong(String) • Float.parseFloat(String) • Double.parseDouble(String) String Parse Instructor: Tanzila Kehkashan 8