Ch no 2 Swings.pdf

SWINGS Marks 10 COURSE OUTCOME  Develop program using GUI Framework using (AWT & Swing)  java Swing is a part of Java Foundation Classes (JFC) that is used to create window-based applications. It is built on the top of AWT (Abstract Windowing Toolkit) API and entirely written in jav...

SWINGS Marks 10 COURSE OUTCOME  Develop program using GUI Framework using (AWT & Swing)  java Swing is a part of Java Foundation Classes (JFC) that is used to create window-based applications. It is built on the top of AWT (Abstract Windowing Toolkit) API and entirely written in java.  Unlike AWT, Java Swing provides platform- independent and lightweight components.  The javax.swing package provides classes for java swing API such as JButton, JTextField, JRadioButton,JComboBox, JCheckbox, JTabbedPane, JScrollPane,Jtree,JTable.JProgressBar etc. DIFFERENCE BETWEEN AWT & SWING MVC ARCHITECTURE Swing API architecture follows loosely based MVC architecture in the following manner.  Model represents component's data.  View represents visual representation of the component's data.  Controller takes the input from the user on the view and reflects the changes in Component's data.  Swing component has Model as a seperate element, while the View and Controller part are clubbed in the User Interface elements. Because of which, Swing has a pluggable look-and-feel architecture. SWING FEATURES  Light Weight − Swing components are independent of native Operating System's API as Swing API controls are rendered mostly using pure JAVA code instead of underlying operating system calls.  Rich Controls − Swing provides a rich set of advanced controls like Tree, TabbedPane, slider, colorpicker, and table controls.  Highly Customizable − Swing controls can be customized in a very easy way as visual apperance is independent of internal representation.  Pluggable look-and-feel − SWING based GUI Application look and feel can be changed at run-time, based on available values. WHAT IS JFC  The Java Foundation Classes (JFC) are a set of GUI components which simplify the development of desktop applications.  Features of JFC  Swing GUI components.  Look and Feel support.  Java 2D. AWT AND SWING HIERARCHY SWING CLASSES  Japplet  JApplet is a class that represents the Swing applet.  It is a subclass of Applet class and must be extended by all the applets that use Swing.  Japplet is rich in functionality that is not found in applet ex Japplet supports various panes i.e Content pane,glass pane.  Whenever we require to add a component to it, the component is added to the content pane.  Syntax Container getContentPane();  The add() of container can be used to add a component to a content pane void add(comp); IMAGEICON  A ImageIcon control is an implementation of the Icon interface that paints Icons from Images.  Constructor ImageIcon(String filename) ImageIcon(URL location)  Methods int getIconHeight() int getIconWidth() Image getImage() void paintIcon(Component c, Graphics g, int x, int y) void setImage(Image image) JLABEL  The class JLabel can display either text, an image, or both.  Constructors & Methods PROGRAM import javax.swing.*; import java.awt.*; public class Buttons extends JApplet { Container c; JLabel l1; public void init() { c = getContentPane(); setLayout(new FlowLayout()); ImageIcon i = new ImageIcon("java.PNG"); l1=new Jlabel(“sunset”,I,Jlabel.CENTER); c.add(l1); } } PROGRAM import javax.swing.*; class LabelExample { public static void main(String args[]) { JFrame f= new JFrame("Label Example"); JLabel l1,l2; l1=new JLabel("First Label."); l1.setBounds(50,50, 100,30); l2=new JLabel("Second Label."); l2.setBounds(50,100, 100,30); f.add(l1); f.add(l2); f.setSize(300,300); f.setLayout(null); f.setVisible(true); } } PROGRAM import javax.swing.*; import java.awt.*; import java.applet.*; class LabelExample1 extends JFrame { JLabel l1,l2; public LabelExample1() { setLayout(new FlowLayout()); l1=new JLabel("First Label1."); l2=new JLabel("Second Label2."); add(l1); add(l2); } public static void main(String args[]) { LabelExample1 f=new LabelExample1(); f.setSize(400,600); f.setVisible(true); } } JCheckBox The JCheckBox class is used to create a checkbox. It is used to turn an option on (true) or off (false). Clicking on a CheckBox changes its state from "on" to "off" or from "off" to "on ".It inherits JToggleButton class. Constructors & Methods PROGRAM import javax.swing.*; import java.awt.*; public class check extends JApplet { Container c; public void init() { c = getContentPane(); setLayout(new FlowLayout()); JCheckBox c1=new JCheckBox("male"); c.add(c1); JCheckBox c2=new JCheckBox("Female"); c.add(c2); } }  o/p JBUTTON  The class JButton is an implementation of a push button. This component has a label and generates an event when pressed. It can also have an Image.  Constructors & Methods JRADIOBUTTON  The JRadioButton class is used to create a radio button. It is used to choose one option from multiple options.  Constructors & Methods PROGRAM import javax.swing.*; import java.awt.*; public class radio extends JApplet { Container c; public void init() { c = getContentPane(); setLayout(new FlowLayout()); JRadioButton b1=new JRadioButton("male"); c.add(b1); JRadioButton b2=new JRadioButton("Female"); c.add(b2); ButtonGroup bg=new ButtonGroup(); bg.add(b1); bg.add(b2); } }  Output JCOMBOBOX  JComboBox is like a drop down box — you can click a drop-down arrow and select an option from a list.  Constructor o Methods PROGRAM import javax.swing.*; import java.awt.*; public class Combo extends JApplet { Container c; JComboBox j; public void init() { c = getContentPane(); setLayout(new FlowLayout()); j= new JComboBox(); j.addItem("India"); j.addItem("srilanka"); j.addItem("pakistan"); c.add(j); } }  Output JSCROLLPANE A JscrollPane is used to make scrollable view of a component. When screen size is limited, we use a scroll pane to display a large component or a component whose size can change dynamically.  Constructors  ScrollPaneConstants are ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED; ScrollPaneConstants.VERTICAL_SCROLLBAR_NEVER; ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS; ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED; ScrollPaneConstants. HORIZONTAL_SCROLLBAR_NEVER; ScrollPaneConstants. HORIZONTAL_SCROLLBAR_ALWAYS import javax.swing.*; import java.awt.*; import java.applet.*; public class scroll extends JApplet { Container c; JScrollPane j; public void init() { c = getContentPane(); c.setLayout(new BorderLayout()); JPanel p=new JPanel(); for(int i=0;i