Java AWT Quiz & Flashcards: Chapter 1 Components

Study Notes

AWT is a Java API to develop graphical user interface (GUI) or windows-based applications.
AWT components are platform-dependent, i.e., they are displayed according to the view of the operating system.
AWT is heavy weight, i.e., its components use the resources of the underlying operating system (OS).
AWT is a GUI library that provides packages and classes to add graphical components (e.g., buttons, text boxes, check boxes) to applications.

AWT is a set of native user interface components.
It is based on a robust event-handling model.
It provides graphics and imaging tools, such as shape, color, and font classes.
AWT avails layout managers, which help in increasing the flexibility of window layouts.
It includes data transfer classes that help in cut-and-paste through the native platform clipboard.

A container is a component that holds other components.
A container is a subclass of java.awt.Component and is responsible for keeping track of components being added.
There are four types of containers:
- Window: A window with neither border nor title.
- Frame: A frame with title, border, and menu bars.
- Dialog: A dialog with border and title.
- Panel: A generic container for holding GUI components.

java.awt.Button: A labeled button that triggers a certain programmed action upon clicking.
java.awt.TextField: A single-line text box for users to enter texts.
java.awt.Label: A descriptive text string that is visible on the GUI.
java.awt.Canvas: A rectangular area where you can draw or receive user inputs.
java.awt.Choice: A pop-up menu of choices.
java.awt.ScrollBar: A horizontal and vertical scrollbar in the GUI.
java.awt.List: A list of text items.
java.awt.CheckBox: A graphical component with two states: true and false.

A calculator application can be developed using AWT components, such as buttons, text fields, and labels.
The application can perform basic mathematical operations, such as addition, subtraction, multiplication, and division.### Card Layout Manager
Each card is like a playing card in a stack, where only the top card is visible at any time.
The Card Layout Manager is used to manage components in a stack.
Each card is normally a panel that can use any layout manager.

The GridBag layout manager manages components in rows or columns, allowing specified components to span multiple rows and columns.
Not all rows and columns have the same height and width.
This is the most complex layout manager, as it specifies the size and position characteristics of its components by specifying constraints for each component.
Example code is provided to illustrate the use of GridBagLayout.

The MenuItem class adds a simple labeled menu item on a menu.
The Menu class is a pull-down menu component that is displayed on the menu bar.
Menus are very familiar to programmers in the Windows environment.
A menu has a pull-down list of menu items from which the user can select one at a time.
A click on the MenuItem generates an ActionEvent and is handled by an ActionListener.
A Menu and a MenuItem are not components, as they are not subclasses of the java.awt.Component class.
They are derived from the MenuComponent class.

The abstract class that is the superclass of all menu-related classes is MenuComponent.
The most commonly used layout managers are Flow layout, Border layout, and Grid layout.
The default layout manager for subclasses of Window is BorderLayout.
Each menu is associated with a drop-down list of menu items.