The interface should be implemented to listen for a button action event.
focuslistener
containerlistener
actionlistener
windowlistener

The correct answer for the given fill in the blank is " ActionListener"

Explanation:

The ActionListener interface is to listen for button action event. or menu item.

Following are the method of  ActionListener interface

i.e  actionPerformed()

This method invoked automatically whenever you click on button.

Following are the steps to implement ActionListener

Firstly The ActionListener interface is implements in your class:

for example :i.e public class Action1 Implements ActionListener

In second step Registered the component by using addActionListener() method

i.e component.addActionListener(object of Listenerclass);  

In the last step Override the method actionPerformed()

i.e:public void actionPerformed(ActionEvent e1)

{  

    //statement  or  code

}  

The FocusListener listen the keyboard focus event so this option is wrong.

ContainerListener  is used for receiving container events so this option is wrong.

WindowListener is used for receiving window events so this option is wrong.

So the correct answer is ActionListener.

a software engineer i believe

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