Inner Classes - when to use with Swing?

Hi again,
I was creating a GUI with JTabbedPane as content pane, while doing the single panes in the different tabs i started wondering about some design issues.
Let�s say you have a pane that is composed of 3 "subpanes" ( containing all the interaction components ). Should i write "normal" classes for each of the subpanes or is it more reasonable to define them as inner classes of the "main" panel - that�s at least what i thought because those 3 smaller panels are bound to the main panel for their lifetime...
Any design tips about inner classes and swing or even inner classes in general, i�d really appreciate.
Thx

The concept of inner classes design in java is (I hope) they provide 'composite aggregation' relation with the contained class.
Means that the (inner) class cannot exists alone and provide functionalities like other classes. Inner classes refer to the "contains" relationship in the UML.
The other regular associations say, having a value oject model to an UI are Structural Aggregation, means that the value object can be used in the UI and also separately.
For your case the inner classes are not suitable. You may have to find a suitable mechanism to get the individual tab panes. Probably use an interface to bridge the three tab panes and use an manager class, pass and id to the manager class and get the required Tabbed pane.
Thanks,
ananth
Hi again,
I was creating a GUI with JTabbedPane as content pane,
while doing the single panes in the different tabs i
started wondering about some design issues.
Let�s say you have a pane that is composed of 3
"subpanes" ( containing all the interaction components
). Should i write "normal" classes for each of the
subpanes or is it more reasonable to define them as
inner classes of the "main" panel - that�s at least
what i thought because those 3 smaller panels are
bound to the main panel for their lifetime...
Any design tips about inner classes and swing or even
inner classes in general, i�d really appreciate.
Thx

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>
But you have added code only with the sole intent of
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>>
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If so, can someone please show me how?
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import java.awt.event.*;
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Below is modification of above code to a JApplet
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import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
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1. Is purpose of inner class in an Application to
take care of what init method
takes care of in a JApplet. I believe init method in
JApplet brings up the browser and
xecutes statements in init()?No. The init() method of an applet is similar to the constructor for an application. It is used to initialize data for the applet, the same data you will initialize in the constructor of the application.
>
2. Is it possible to write the enclosed Application
without using an Inner Class?Yes it is possible. The power of an inner class is that is has access even to private member variables of the enclosing class. In your case the event handler has access to the private variables: numField and sumField. If you do not use an inner class you have to pass a reference to your frame in the event handler's constructor and access the variables through that reference. But in this case you do not have access to private variables. So you must provide methods to access those variables or you must change theri visibility.
ActionEventHandler handler = new ActionEventHandler(this);Provide accessor methods in InnerTest class:
public String getTextString(){
return numField.getText();
public void setTextString(String text){
numField.setText(text);
}As for the applet it works just as your application in this case, you can use inner classes or not but with the same restrictions.
I hope you can understand what I tried to explain.

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From a subclass of Action I have created as a (non-static) inner class of a JFrame, I wish to reference the parent JFrame in a JFileChooser invocation, so something like:JFileChooser.showSaveDialog(**this**);with **this** being the parent JFrame.
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