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#BUTTONBAR STYLE JAVA WINDOWS#

Now we can see that as soon as we click on the button, the background color of the JFrame has been changed to pink.

Now save the program, compile it and run it.

In this program, we need to import another new package because we are dealing with event handling and this package provides classes and interfaces that are used for event handling in awt and Swing.

In the first step, we need to import all essential packages.

Handling Java Swing Button Click Event Step by Step Importing Packages So this was the brief description of event classes and listeners, and now we will see Java Button Click Event or Swing JButton click action using JFrame step by step in which we will learn about the JButton ActionListener interface, ActionPerformed() method and addActionListener() method.

#BUTTONBAR STYLE JAVA WINDOWS#

Some common event classes in the package are given below : Events Classes Description ActionEvent Generated when an action has occured (e.g- button pressed) AdjustmentEvent Generated when scroll bar is manipulated ContainerEvent Generated when container is changed ( added or removed ) FocusEvent Generated when component’s keyboard focus is changed InputEvent Abstract superclass of KeyEvent and MouseEvent ItemEvent Generated when an item is selected or deselected KeyEvent Generated when input is given through keyboard MouseEvent Associated with the mouse events TextEvent Generated when value of text area or text field is changed WindowEvent Associated with the windows related events Event Classes and Associated Listener Interfaces Event Classes Associated Listener Interface ActionEvent ActionListener AdjustmentEvent AdjustmentListner ContainerEvent ContainerListener FocusEvent FocusListener ComponentEvent ComponentListener ItemEvent ItemListener KeyEvent KeyListener MouseEvent MouseListener TextEvent TextListener WindowEvent WindowListener.Package is used for defining interfaces and classed that is used for event handling in AWT and SWING.AWTEvent is a subclass of EventObject class and it is superclass for all AWT events.getSource() method returns the source and toString() method returns the string equivalent of the event.EventObject is the superclass for all events which means it is the root of the Java event class hierarchy.Some common Java interfaces and the events they listen for and handle : Java Interfaces Event They Listen ActionListener Listens for and handles button clicks KeyListener Listens for and handles key events MouseListener Listens for and handles mouse events MouseMotionListener Listens for and handles mouse drag and move events TextListener Listens for and handles text changing events ItemListener Listens for and handles CheckBox and Listbox events AdjustmentListener Listens for and handles scrolling events Runnable Listens for and handles Threads and Run WindowListener Listens for and handles window events FocusListener Listens for and handles focus events Event Classes.It must implement methods to receive and process these notifications.

It must have been registered with one or more sources to receive notifications about specific types of events.

Implementing an interface without adding its required abstract methods result in a syntax error.

Listeners are Java interfacesand since we are covering advance topics you must have the knowledge of interfaces that when we implement an interface by a class we must implement all interface’s methods because all the methods in an interface are abstract.

It is an object which is notified when an event occurs.

A method getSource() is associated with all events which returns the object on which the event is initially occurred.

A source can generate one or more types of events.

This happens when the internal state of the object changes in some way.

A source is an object that generates an Event.Events are supported by number of packages including java.util, java.awt,.Some examples of the events are Java Button Pressed Event, entering a character via keyboard, selecting an item in a list, clicking the mouse etc.Basically they are associated with a component.It is an object which describes a change in a source.

4 Which Event is Performed on the Button Click in Java? Java Button Click Event What is An Event ?.3 Which Method is Used to Handle Button Click Event?.2.6 Registering ActionListener to the JButton.2.5 Implementing ActionListener Interface.2.3 Creating another class ActionEventDemo.java.2 Handling Java Swing Button Click Event Step by Step.1.5 Event Classes and Associated Listener Interfaces.