Applets

public void actionPerformed(ActionEvent event) {

   // check to see if the source of the event was a button

   if(event.getSource() instanceof Button) {

      // do whatever it is you want to do with buttons...

   }

}

Darryl L. Pierce Visit <

http://welcome.to/mcpierce

>

 Q: Could you suggest how to draw one centimeter grid in applet, please? One cm on the screen

must be equal to real cm.

Answer: If you re not all that picky about it, you can always use java.awt.Toolkit s

getScreenResolution() to see how far between the lines should be in the grid....that s assuming the

applet security allows it.

But have it _exactly_ one cm, you can t do, since the user can always adjust the display with the

monitor controls (making the picture wider/taller/whatever), and no computer that I know of can know

those settings.

Fredrik Lannergren 

Not only that, the OS (and thus Java) does not know if I am using a 21" or a 14" monitor and thus

can t know the actual physical size of a given number of pixels. By convention, on Windows monitors

are assumed to be either 96dpi or 120dpi (depending on the selection of large or small fonts). Java

usually assumes 72dpi. None of these values is likely to be 

accurate.

Mark Thornton

Q: Does anyone know how to or where I can find information about determining if cookies are

disabled on a client browser making a request to a servlet or JSP (or any server side request handler,

for that matter)? Also, is there a way to determine whether or not a client s browser has style sheets

enabled?

Answer: To test if the client has cookies enabled, create a cookie, send it, and read it back. If you

can t read it back, then the client does not accept them. It s not a clean way of doing it, but it s the only

way (that I know if).

As for CSS, there is no way to know if they allow CSS. Different versions of the browsers support

varying levels of CSS. You can get the browser type from the request object and then make decisions

based on that.

 Q: How can two applets communicate with each other? Have you some examples?

Answer: You will occasionally need to allow two or more applets on a Web page to communicate with

each other. Because the applets all run within the same Java context that is, they are all in the same

virtual machine together applets can invoke each other s methods. The AppletContext class has

methods for locating another applet by name, or retrieving all the applets in the current runtime

environment

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