What is AbstractAction in Java?
public abstract class AbstractAction extends Object implements Action, Cloneable, Serializable. This class provides default implementations for the JFC Action interface. Standard behaviors like the get and set methods for Action object properties (icon, text, and enabled) are defined here.
What is the purpose of action interface in Swing?
In addition to the actionPerformed method defined by the ActionListener interface, this interface allows the application to define, in a single place: One or more text strings that describe the function. These strings can be used, for example, to display the flyover text for a button or to set the text in a menu item.
What is e getSource method in Java?
Description. object getSource() Returns the object on which the event occurred. You can use the getSource method to determine which component sourced the event when the listener is registered as an event listener with more than one component.
What is JPanel in Java Swing with example?
JPanel, a part of the Java Swing package, is a container that can store a group of components. The main task of JPanel is to organize components, various layouts can be set in JPanel which provide better organization of components, however, it does not have a title bar.
What is Java ActionEvent?
public class ActionEvent extends AWTEvent. A semantic event which indicates that a component-defined action occurred. This high-level event is generated by a component (such as a Button ) when the component-specific action occurs (such as being pressed).
What is function method in Java?
A method is a block of code which only runs when it is called. You can pass data, known as parameters, into a method. Methods are used to perform certain actions, and they are also known as functions.
What is actionPerformed method in Java?
The method actionPerformed handles all the actions of a component, and inside this method, you will define or write your own codes that will be executed when an action occurred. Here’s an example on how to implement ActionListener in Java.
What is ActionListener in Java Swing?
Java ActionListener Interface. The Java ActionListener is notified whenever you click on the button or menu item. It is notified against ActionEvent. The ActionListener interface is found in java. awt.
What is ItemEvent in Java?
public class ItemEvent extends AWTEvent. A semantic event which indicates that an item was selected or deselected. This high-level event is generated by an ItemSelectable object (such as a List) when an item is selected or deselected by the user.
What is repaint method in Java?
The repaint method is an asynchronous method of applet class. When call to repaint method is made, it performs a request to erase and perform redraw of the component after a small delay in time.
What are the action and abstractaction classes in swing?
Here’s a quick blurb on the Java Action and AbstractAction classes from the Swing Tutorial: An Action can be used to separate functionality and state from a component. For example, if you have two or more components that perform the same function, consider using an Action object to implement the function.
What does abstractaction do in Java?
AbstractAction(String name) Creates an Action with the specified name. AbstractAction(String name, Icon icon) Creates an Action with the specified name and small icon. addPropertyChangeListener(PropertyChangeListener listener) Adds a PropertyChangeListener to the listener list.
How does the Java/Swing API work?
As you can see, the Java/Swing API is built to expect and use the Java Action class, and once you’ve defined your Action, all of this is very straightforward. Now that you’ve seen the background information, here’s the source code for a complete Java class which shows several custom actions which extend the Java AbstractAction class:
How do I use abstractaction in a jmenuitem?
Using your AbstractAction in a Java menu or toolbar. Once you have an instance of an AbstractAction-based class, you can just create a JMenuItem like this: // create the java menu item, giving it our action JMenuItem cutMenuItem = new JMenuItem(cutAction);