Re: AbstractAction

toton wrote:
[reordered]
Thomas Fritsch wrote:

toton wrote:

From Java 1.5 or lower version, can an Action be used for JCheckBox &
JCheckBoxMenuItem pair or JToggleButton & JCheckBoxMenuItem pair?

JCheckBox, JCheckBoxMenuItem, JToggleButton and JCheckBoxMenuItem all
have a constructor taking an Action. They also have a setAction(Action)
method inherited from AbstractButton.


Java 1.6 has Action.SELECTED_KEY but 1.5 doesnt have.

So what?


Also how to execute an Action from program? like JButton has a
doClick method. I want to execute an action from program even when the
actual button or menuitem is removed from gui, thus i dont have an
reference for the actual gui component.

You can do
Action a = ...;
ActionEvent e =
new ActionEvent(this, ActionEvent.ACTION_PERFORMED, "bla";
a.actionPerformed(e);

> Thanks for the answer.
> For programatically performing action, I used the command pattern
> (design patterns by GoF) which extends AbstractAction & has an execute
> method. A convinent way.
> For the first question i am still unclear that how an action will know
> the component's selected state & take decision as SELECTED_KEY is
> missing.
ActionEvent has (inherited from Action) a getSource() method. Calling it you usually get the component which raised the event. If the component is a JCheckBox/JToggleButton/... you can cast it and call its isSelected() method.

> In that case I have to pass the actual component in the
> action? (Then for the components constructor wont work, neew to use
> setAction instead, also the very basic idea of using one action for
> multiple component will be violeted, as two action is needed for those
> two components).
> Or I need to pass the selected state to action additionally.

--
Thomas
.

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