This document discusses different GUI components and layout managers in Java. It covers the Abstract Window Toolkit (AWT), common components like Frame and Panel, and layout managers including FlowLayout, BorderLayout, and GridLayout. Key points include: 1. AWT provides GUI classes for Java like Frame, Panel, Button and layout managers. 2. Frame is a top-level container that can contain other components. Panel is used to group components and is usually included in a Frame. 3. Layout managers determine how components are arranged. FlowLayout arranges components left-to-right, BorderLayout divides the container into regions, and GridLayout uses a grid of equal cells.

1. 09 GUIs HUREE University ICT Instructor: M.J LEE

2. Contents Abstract Window Toolkit Container Frame Panel Layout Manager Flow Layout Border Layout Grid Layout 2

5. Panel Use add() method, when adding components Panel can’t be displayed by itself. Therefore, it should be included in Frame Some components are disposed in Panel by Layout Manager 5

6. 6 import java.awt.*; public class FrameWithPanelextends Frame { public FrameWithPanel (String str) { super(str); } } Public class FrameWithPanelMain() { public static void main (String args[]) { FrameWithPanelfr = new FrameWithPanel(“Panel in Frame"); Panel pan = new Panel(); fr.setSize(200,200); // a frame fr.setBackground(Color.blue); fr.setLayout(null); pan.setSize(100,100); // a panel pan.setBackground(Color.yellow); fr.add(pan); // put the panel in the frame fr.setVisible(true); } } Panel

7. Layout Manager FlowLayout Panel, default Layout manager of Applet BorderLayout Window, default Layout manager of Frame GridLayout CardLayout GridBagLayout 7

8. 8 import java.awt.*; public class ExGui { private Frame f; // declarationFrame private Button b1; // declaration Button private Button b2; public void go() { f = new Frame("GUI example"); f.setLayout(new FlowLayout()); b1 = new Button(“Yes”); b2 = new Button(“No"); f.add(b1); // append Button on Frame f.add(b2); f.pack(); // instead of “.setSize()” f.setVisible(true); } } public static ExGuiMain() { public static void main(String args[]) { ExGuiguiWindow = new ExGui(); guiWindow.go(); } } 1. Flow Layout

9. Layout Manager –1.Flow Layout At above example, which didn't inherit Frame, declared new frame in the class Properties, Flow Layout Manager is a default layout manager of Panel depose components from left to right! depose components at the middle of Frame, as default decide the size of components by itself It is possible to exchange attributes by using constructor 9 setLayout(new FlowLayout(FlowLayout.RIGHT, 20, 40))

10. Layout Manager –1.Flow Layout Components are disposed at right side. Gap of left and right between components Gap of top and bottom between components (unit: pixel) 10 setLayout(new FlowLayout(FlowLayout.RIGHT, 20, 40)) 1 2 3

11. 11 import java.awt.*; public class MyFlow { private Frame f; private Button button1, button2, button3; public void go() { f = new Frame("Flow Layout"); f.setLayout(new FlowLayout()); button1 = new Button("Ok"); button2 = new Button("Open"); button3 = new Button("Close"); f.add(button1); f.add(button2); f.add(button3); f.setSize(100,100); f.setVisible(true); } } Public class MyFlowMain() { public static void main(String args[]) { MyFlowmflow = new MyFlow(); mflow.go(); } } 1. Flow Layout

12. 12 import java.awt.*; public class ExGui2 { private Frame f; private Button bn, bs, bw, be, bc; public void go() { f = new Frame("Border Layout"); bn = new Button("B1"); bs = new Button("B2"); bw = new Button("B3"); be = new Button("B4"); bc = new Button("B5"); f.add(bn, BorderLayout.NORTH); f.add(bs, BorderLayout.SOUTH); f.add(bw, BorderLayout.WEST); f.add(be, BorderLayout.EAST); f.add(bc, BorderLayout.CENTER); f.setSize(200,200); f.setVisible(true); } public static void main(String args[]) { ExGui2 guiWindow2 = new ExGui2(); guiWindow2.go(); } } 2. Border Layout

13. 13 2. Grid Layout import java.awt.*; public class TestGrid { private Frame f; private Button b1, b2, b3, b4, b5, b6; public void go() { f = new Frame(“Grid Layout"); f.setLayout (new GridLayout(3,2)); b1 = new Button("1"); b2 = new Button("2"); b3 = new Button("3"); b4 = new Button("4"); b5 = new Button("5"); b6 = new Button("6"); f.add(b1); f.add(b2); f.add(b3); f.add(b4); f.add(b5); f.add(b6); f.pack(); f.setVisible(true); } public static void main(String args[]) { TestGrid grid = new TestGrid(); grid.go(); } }

14. Layout Manager –3.Grid Layout Add(): components are disposed from left to right, upside to bottom The size of each cell, which is divided by Grid Layout Manager, is same. The number of cells can be defined when they are created with Constructor. f.setLayout (new GridLayout(3,2)); 14