1. Responding to Events Event Handling in Java
Making the UI Work
Responding to Events
Event Handling in Java

2. Event Handling Event Handling Consist of the following 3 things Events
Event Sources / Generators
Event Listeners / Handlers
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3. Event An action which is recognized by an object is known as an Event
For example.
Moving the mouse pointer over button and clicking over the button
Specific Event Listeners are available for handling specific events.
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4. Some Events, ActionEvent ItemEvent AdjustmentEvent KeyEvent
Such as mouse clicks and Enter key presses
ItemEvent
Such as selecting an item from a dropdown list box
AdjustmentEvent
Such as moving a scrollbar
KeyEvent
Such as pressing a key on the Keyboard
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5. Event Sources / Generators
Components which can generate the events are commonly known as event sources or event generators.
Examples
Button Scrollbar Checkbox Choice TextField
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6. Event Listeners / Handlers
These are special kind of java Interfaces (type of java program) that is used to handle the events.
Each Listener is built with one or more methods to respond to event,
Before these Listeners can handle the events for you, you must register the components with the relevant Event Listener refer the code samples for more information.
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7. Question (s)
Create an UI with two buttons, when you click on the first button the second button’s position should change.
Create an UI to enter a number and display in a label EVEN or ODD with 2 different colors
Create an UI with two TextFields and one button once you type something in the TextField and click the button count the number of characters in the 1st textfield and display it in the 2nd TextField.
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