Re: [Jython-users] HelloWorld for Jython 2.5 applets

[Josh J. <jun...@gm...>]

Rasjid/Marcos-

This approach has also crossed my mind.  I'd really like to implement
something in the PlyJy project that would allow for one to create a Jython
applet without worrying about the object factory design.  I started an
implementation some time ago, but was never really able to embed the
resulting applet into a webpage and make it work.  Perhaps with a little
more time we can come up with a variant of my implementation that would make
this approach usable.

So far, I've created a "test" facade which is actually a Java applet class
which invokes the PythonInterpreter from within the init() method.
 Basically, the Jython code is not really an applet in this approach, but
rather just swing code that is added to this applet facade.  In the end, the
facade would be the embedded applet and it would call to the Jython code to
create the actual GUI.  The implementation I've started is not reusable and
we'd have to take it a step further in order to make it so, but it is a
start.

AppletFacade.java - This is the actual (likely reusable at some point)
applet that will become part of PlyJy.  In this hard-coded implementation I
am instantiating a Jython module named "Ouch" which simply places a button
on the applet.  Maybe this could be an abstract class in a reusable
implementation.

package org.plyjy.facade;

import java.util.ArrayList;
import java.util.List;
import javax.swing.JApplet;
import javax.swing.SwingUtilities;
import javax.swing.JLabel;
import org.plyjy.factory.JythonObjectFactory;
import org.plyjy.factory.PySystemObjectFactory;
import org.plyjy.interfaces.AppletType;

public class AppletFacade extends JApplet {

    private String appletClass = "Ouch";
    private List argList = new ArrayList();

    //Called when this applet is loaded into the browser.
    @Override
    public void init() {

        // Add a reference to this applet into our list...this will be
passed to the Jython code
        this.argList.add(this);
        //Execute a job on the event-dispatching thread; creating this
applet's GUI.
        try {
            SwingUtilities.invokeAndWait(new Runnable() {
                public void run() {
                    PySystemObjectFactory factory = new
PySystemObjectFactory(
                    AppletType.class, appletClass, appletClass);

                    AppletType app = (AppletType) factory.createObject();

                    app.run_applet(argList);
                 }
            });

        } catch (Exception e) {
            System.err.println("createGUI didn't complete successfully " +
e);
        }
    }

    public void setArgList(){
        // Empty method to override...perhaps use to load values in reusable
case?
    }
}


AppletType.java - This is the interface which all Jython GUI code will need
to implement in our solution

package org.plyjy.interfaces;

import java.util.List;

public interface AppletType {
    public void run_applet(List args);
}


Ouch.py - Adds a button to the applet.  We can create a GUI here and simply
add it to the applet object which is passed in via the argList.

import javax.swing as swing
from org.plyjy.interfaces import AppletType

class Ouch (AppletType):

    def init(self):
        # Probably do something else here....just a test
        self.frame = None
        self.button = None

    def print_message(self, event):
        print "Ouch!"

    def run_applet(self, *args):
        arrayList = args[0]
        self.frame = arrayList.get(0)
        self.button=swing.JButton("Push Me!",
actionPerformed=self.print_message)
        self.frame.contentPane.add(self.button)


Like I said, this approach runs fine on my desktop, but it doesn't work when
I embed it into an HTML page.  Perhaps I just need to work a bit with it to
make it happen.  I haven't committed this code to PlyJy as I wanted to make
it function properly first.  However, perhaps it would be desirable for me
to commit it so that others can work on it as well. :)

Is this the idea you had in mind Marcos?

Best

Josh Juneau
jun...@gm...
http://jj-blogger.blogspot.com
http://www.jythonpodcast.com
Twitter ID:  javajuneau


2010/1/26 Rasjid Wilcox <ra...@gm...>

> 2010/1/27 Marcos Sánchez Provencio <msa...@gr...>
>
> But you can use a pythoninterpreter in your applet classes, can't you?
>> You just have to include your py sources as resources. I have a test
>> applet that adds 2+2 and show sys.version. In theory, you could add your
>> jython java object factory to this mix...
>>
>> By the way, what is the minimal set of permissions for jython to work? I
>> am testing with
>> grant {
>>  permission java.security.AllPermission;
>> };
>>
>> Rasjid, is that close to what you wanted?
>>
>>
> Yes, this approach occurred to me late last night.  If you can share your
> test applet, that would be great, since I'd be kind of working it out from
> scratch. (I have minimal exposure to Java.)
>
> Cheers, Rasjid.
>
>