File	Doc	Category	Size	Date	Package
event.java	API Doc	Example	5174	Thu Sep 07 10:51:46 BST 2000	None

event

• java.lang.Object
  • java.awt.Component
    • java.awt.Container
      • java.awt.Panel
        • java.applet.Applet

Fields Summary
private TextField	input
private int	choice

Constructors Summary

Methods Summary
public void	actionPerformed(java.awt.event.ActionEvent event) // The line below converts the 'string' in the textfield to // an integer... choice = Integer.parseInt (input.getText()); // Now the choice has been entered, repaint the applet... // This will cause the routine 'paint' to be called. You can insert all your code into // paint confident that it will be run as a result of the repaint command. repaint();
public void	init() Label menu1, menu2, menu3; // Create a menu using 'Labels' menu1 = new Label("Choice 1 = draw colour graph"); menu2 = new Label("Choice 2 = draw colour pie chart"); menu3 = new Label("Choice 3 = print colour table"); add(menu1); add(menu2); add(menu3); input = new TextField(10); add (input); // addActionListener will cause the routine 'actionPerformed' to be invoked // when new data is entered in the textfield... input.addActionListener(this);
public void	paint(java.awt.Graphics g) // Here you can do something with the variable 'choice' confident that it has // been set to some meaningful value in the routine 'actionPerformed'... // Also check for errors in the input. E.g. if the choice lies outside the // acceptable range then tell the user using some appropriate message. // Parameters for drawing pie chart double startAngle = 0.0; double arcAngle; int x = 10; // top left hand screen position (for the pie chart) int y = 100; int width = 200; // The total size of the pie chart int height = 200; arcAngle = 360.0 / 13.0; //(360 degrees divided equally by the 13 available colours) // Parameters for drawing rectangle int rectangle_height = 15; // Parameters for drawing table String colourString = " "; int string_height = 15; for (int colour = 1; colour <= 13; colour++) { // Select the colour switch (colour) { case 1: g.setColor(Color.black); colourString = "Black = 1"; break; case 2: g.setColor(Color.blue); colourString = "Blue = 2"; break; case 3: g.setColor(Color.cyan); colourString = "cyan = 3"; break; case 4: g.setColor(Color.darkGray); colourString = "dark grey = 4"; break; case 5: g.setColor(Color.gray); colourString = "grey = 5"; break; case 6: g.setColor(Color.green); colourString = "green = 6"; break; case 7: g.setColor(Color.lightGray); colourString = "lightgrey = 7"; break; case 8: g.setColor(Color.magenta); colourString = "magenta = 8"; break; case 9: g.setColor(Color.orange); colourString = "orange = 9"; break; case 10: g.setColor(Color.pink); colourString = "pink = 10"; break; case 11: g.setColor(Color.red); colourString = "red = 11"; break; case 12: g.setColor(Color.white); colourString = "White = 12"; break; case 13: g.setColor(Color.yellow); colourString = "Yellow = 13"; break; }// end of switch (colour) switch(choice) { case 1: // Case 1 - draw a colour graph g.fillArc( x, y, width, height, (int)startAngle, (int)arcAngle ); startAngle = startAngle + arcAngle; break; case 2: g.fillRect( x, y, width, rectangle_height); y = y + rectangle_height; break; case 3: g.drawString(colourString, x, y); y = y + string_height; break; default: break; }// End of 'switch' } // end of 'for' loop //g.drawString("Choice 3 = Leave the program",20,60);