chapter-Java GUI Programming Using Swing-I

(a) Graphical User Interface.

Explanation- A Graphical User Interface is an interface that uses graphics along with text to interact with user.

(c)an event handler.

Explanation- An event handler receives and handles events when a button is clicked or key is pressed.

(b)FlowLayout.

Explanation: FlowLayout arranges components in a container like words on a page. If the container is not wide enough to display all of the components, the components wrap around to a new line.

(a)color chooser.

Explanation: The JColorChooser class provides users with a palette of colours to choose from. A color chooser is a component that can be placed anywhere within the program GUI.

(b)label.

Explanation: With the JLabel class, we can display unselectable text and images.

(d)Window.

Explanation- A window is a rectangular portion of the display on a computer monitor that presents its contents (e.g., the contents of a directory, a text file or an image) seemingly independently of the rest of the screen.

(a) internal frame.

Explanation- With the JInternalFrame class we can display a JFrame-like window within another window.

(a)Event.

Explanation- Events represent all activity that goes on between the user and the application.

(b) Abstract Window Toolkit.

Explanation- Abstract Window Toolkit is a basic GUI toolkit of Java platform. Swing internally borrows functionality from AWT.

(c) Source.

Explanation- It is the GUI component that generates the event, e.g., a button etc.

(d) BorderLayout.

Explanation- BorderLayout arranges components along the edges or the middle of their containers.

(a)setBounds.

Explanation- Used to set the absolute size and location of a Component.

(a) Uneditable combo box.

Explanation- Uneditable combo box display a list from which users can select one item.

(b) setJMenuBar

Explanation- Sets the menubar for this frame.

(b) setEnabled (boolean b)

Explanation- setEnabled (boolean b), enables or disables this component, depending on the value of the parameter b. An enabled component can respond to user input and generate events. Components are enabled initially by default.

(a) LEFT.

Explanation- In FlowLayout Manager, the first component added appears to the left and subsequent components flow in from the right.

(d) FlowLayout.

Explanation- Default Layout Manager works like a typical word processor from Left to Right. The order in which the components are added determines their order in the container.

(a) Swing component.

Explanation- A Swing component is a self-contained graphic entity that can be customized and inserted into applications. Example: Jlabel, Jbutton etc.

(c) Special Purpose Containers.

Explanation- Special Purpose Containers are intermediate containers that play specific roles in the UI.

(c) Basic Controls.

Explanation- Basic Swing Controls are simple components that are used primarily to get input from the user.

(b)GridLayout.

Explanation- GridLayout places components in a grid of equally sized cells, adding them to the grid from left to right and top to bottom. Each region of the grid will have the same size.

(d)mouse moves over a component.

Explanation- Mouse motion events occur when a mouse is moved over a component. To handle a Mouse motion event the mouse motion listener interface must be implemented.

(c)an object.

Explanation- An object is an identifiable entity with some characteristics.

(a) actionCommand.

Explanation- actionCommand sets string that would identify the command associated with button.

(a)lightweight components.

Explanation- A lightweight component directly implements the look-and-feel of the component in Java rather than delegating the look-and-feel to a native peer. Lightweight components can be more efficient at utilizing system resource and they can be transparent

(a)a class.

Explanation- A Class represents a set of similar objects.

(b) class.

Explanation- Once a class is available; we can create many objects that have the same structure and behaviour. If we create two objects they are instances of the same class.

(c) an instance method.

Explanation- An instance method is a method which is associated with one object and uses the instance variables of that object.

(d) Java.

Explanation- Object Oriented Programming or OOP is the technique to create programs based on the real world. Java is a object oriented programming language.

(a) interpreted.

Explanation- At first, the Java source code (in .java files) is compiled into Bytecode. When the Java application is started, the Bytecode is interpreted by the Java Virtual Machine.

(a) a semicolon (;).

Explanation-Every complete Java statement ends with a semicolon.

(a) java bytecode.

Explanation- Java compiler compiles the Java source code files (*.java) into binaries files (*.class). Java bytecode is the form of instructions that the Java virtual machine executes.

(c) lowercase.

Explanation- Keywords are in lowercase and reserved. Lowercase is used for variable and method names.

(c) JPanel.

Explanation- JLabel and JButton are specifically designed with particular features for labels and buttons. They are not appropriate for custom drawing. The problem with JComponent is that you have to write the code to paint the background color if we wish to set a background in the canvas. A simple setBackground (Color) method will not set a background color in a JComponent.

(d) ContainerEvent.

Explanation- The ContainerEvent class extends from the ComponentEvent class. This is a low-level event which is generated when container's contents changes because of addition or removal of a components.

(b)WindowEvent.

Explanation- Frames generate events belonging to the class WindowEvent. The event handler for that event is responsible for closing the window.

(c) listener object.

Explanation- The event listener object contains listener methods for various types of events.

(a) listener interface.

Explanation- Java defines an event listener interface for each of the event types it defines.

(b) ActionListener.

Explanation- The ActionListener interface must be implemented to capture an ActionEvent. This interface provides processAction () method which is called when the ActionEvent for which the ActionListener is registered occurs.

(b) getSource().

Explanation- Every event object is a subclass of EventObject, which contains the getSource() method.

(a) Action Event.

Explanation- A check box generates one item event and one action event per click. Swing supports radio buttons with the JRadioButton.

(d) text field.

Explanation- If we need a component that displays or allows entry of more than one line, a JTextArea can be used.

(d)Unlimited.

Explanation- An editable JComboBox allows the user to add unlimited number of items.

(c) a list.

Explanation- A list is a component that performs basically the same function as a combo box, but it enables the user to choose a single value or multiple values.

(b) a convenience listener adapter.

Explanation- Convenience adapters are support classes that provide default implementations for all the methods in the listener interface.

(c) c.setLayout(null).

Explanation- By setting a container's layout property to null, we make the container use no layout manager.

(d) BoxLayout.

Explanation- BoxLayout allows multiple components to be arranged either vertically or horizontally, but not both.

(b) SpringLayout.

Explanation- The spring may compress or expand to place the components in desired locations.

(a) ActionEvent.

Explanation- MenuItem objects that generate action events when clicked and therefore have addActionListener methods.

(c) JComponent.

Explanation- To create a popup menu, use JPopupMenu which is a subclass of JComponent.

(b) AbsoluteLayout.

Explanation- AbsoluteLayout is a layout manager that enables components to be placed exactly where one want them in the form and resize them using their selection borders.

(c) Item Events.

Explanation- Item Events occur when an item is select6ed or deselected on components like Jbutton, JCheckBox, etc.

(d) property.

Explanation- Event handler can be defined using property sheet, click the value of the desired event in the list.

(a) BorderLayout.

Explanation- By default, content panes use BorderLayout. Components are placed in five possible positions.

(d) SpringLayout.

Explanation- When we need to display a few components in a compact row at their natural size, SpringLayout can be used.

(c)methods.

Explanation- Behaviour of the objects is implemented through functions called as methods.

(c) Object Oriented Programming.

Explanation- OOP is a computer science term which is used to describe a computer application that is composed of multiple objects which are connected to each other.

(b) java.awt.Container.

Explanation- Jcomponent is mostly derived from Java.awt.Window.

(a) AWT and Swing components.

Explanation- Swing components are referred to as lightweights while AWT components are referred to as heavyweights. The difference between lightweight and heavyweight components is z-order: the notion of depth or layering. Each heavyweight component occupies its own z-order layer. All lightweight components are contained inside heavyweight components and maintain their own layering scheme defined by Swing.

(c)a container for a content pane, layered pane, menu bar and glass pane.

Explanation- JRootPane is used to manage a container for a content pane, layered pane, menu bar and glass pane. A JRootPane object is made up of a glassPane, a contentPane and an optional menu bar.

(a) Event-driven programming.

Explanation- Event-driven programming is a flexible way to allow programs to respond to many different inputs or events.

(c) GUI Components, Event Listeners, Application Code.

Explanation- GUI program consists of three types of software:

Graphical Components that make up the Graphical User Interface.

Listener methods that receive the events and respond to them.

Application methods that do useful work for the user.

(b) Mouse.

Explanation- Graphical User Interface makes use of mouse which is user friendly. The mouse can be used to select (copy), and extend-select text, paste text from other terminals or applications, and also bring up control menus, as well as select (and move) other GUI components.

(d) a GUI component that has other GUI components placed inside of it.

Explanation- A container is a component that stores other components and arranges them inside the container according to a Layout manager.

(a) An Event.

Explanation- Whenever we click a mouse button, move the mouse or type on the computer keyboard, we are generating what is referred to as an event.

(c) A listener method.

Explanation- Listener methods are a kind of call back; they are triggered when a form is submitted or a link is clicked.

(d) JComponent.

Explanation- The JComponent class provides the base class for both standard and custom components that use the Swing architecture.

(c) J.

Explanation- Many of the Swing classes representing windows, lists, buttons etc live in the javax.swing package and subpackages. The names of most Swing classes start with the letter J: JFrame, JPanel, JButton, JList etc. In general, if we are looking for the class that represents some visual component in Swing, its name will start with J.

(b) state and behavior.

Explanation- Real-world objects share two characteristics: They all have state and behavior. Bicycles have state (current gear, current pedal cadence, current speed) and behavior (changing gear, changing pedal cadence, applying brakes).

(d)description of a kind of object.

Explanation- A class is the blueprint from which individual objects are created.

(c) A frame.

Explanation- Frame is a Window with controls on it such as optional resizing buttons, an icon, a menubar and a title.

(b) JFrame.

Explanation- JFrame is a java swing public class which is a top level container class.

(a) event listener.

Explanation- Any object can be notified of an event by registering as an event listener on the appropriate event source.

(c) represents one specific event, such as a mouse click.

Explanation- The Event object represents the state of an event, such as the element in which the event occurred, the state of the keyboard keys, the location of the mouse, and the state of the mouse buttons.

(a) addWindowListener().

Explanation- addWindowListener(), adds the specified window listener to receive window events from the window.

(c) TabPane.

Explanation- TabPanes provide the ability to switch betwen various panels. various panels can be added to a top level container using tabbed panes.

(d) Layout Manager.

Explanation- Java applets use layout managers to arrange display components, e.g. buttons, text fields, lists, etc.

(b) FlowLayout.

Explanation- FlowLayout is the default layout manager for every JPanel. It simply lays out components in a single row, starting a new row if its container is not sufficiently wide.

(d) actionPerformed().

Explanation- When the button is clicked, a call is made to the actionPerformed() method defined in the class of the listener object. An ActionEvent object is passed as a parameter to it actionPerformed().

(b) System.exit( 0 ).

Explanation- The code System.exit(0, blindly terminates the application.

(c) JTextComponent.

Explanation-

(a) Jlabel.

Explanation- A label is an object of the class Jlabel.

(a) starting at the top, then left to right in each row.

Explanation- FlowLayout arranges components in a container like words on a page. It fills the top line from left to right.

(a) when the field has focus and the enter key is hit.

Explanation- A TextField generates an ActionEvent when the user enters text and presses enter.

(c)setBackground()

Explanation- Sets the background colour of the component.

(c) layout manager.

Explanation- A layout manager is an object that implements the Layout Manager interface and determines the size and position of the components within a container.

(b) The layout manager changes the layout and re-distributes the components.

Explanation – Although components can provide size and alignment hints, a container's layout manager has the final say on the size and position of the components within the container.

(a) collection of constants and method declarations.

Explanation- A interface is a collection of data attributes and methods that define the semantics of the interface. An interface is a collection of constants (not fields) and method declarations. The method declarations do not include an implementation (there is no method body.)

(b) It must declare and provide a method body for each method in the interface.

Explanation- When a class implements an interface it must declare and provide a method body for each method in the interface. All of the methods declared in an interface are implicitly abstract.

(d) WindowListener.

Explanation- WindowListener is the listener interface for receiving window events.

(a) attributes.

Explanation- An object that can hold data is called member variable or attributes; the value of these attributes defines the state of an object.

(a) frame.

Explanation- A frame is a top-level window with a title and a border. A frame is created through JFrame component.

(b) panel.

Explanation- A panel is a type of container that is designed to hold a group of components so that they can be displayed on a frame.

(c) target, selector and parameter list.

Explanation- Java implements messages as method calls. A message has three components: a target, a selector and a parameter list.

(d) JButton class.

Explanation- Push Button are created through JButton class of Swing API. We can control the look and fell of the button.

(a) mnemonic property.

Explanation- To assign a keyboard access key to a command button, we need to set the mnemonic property of the button by simply typing the key in the box in front of mnemonic property in Properties window.

(b) Action Event.

Explanation- The most common event of push buttons (JButton) is Action Event, which is handled by ActionPerformed () method of event listener ActionListener.

(c) Start button().

Explanation- Start button(StartBtn) initiates the counting process by initializing the value as 0 in the label.

(b) class.

Explanation- A class represents a set of objects that have a common structure and common behaviour. Class is a blueprint that represents a set of similar objects.

(c) custom code.

Explanation- To set iconImage property of a frame, we need to select ellipsis of iconImage property and select Custom code from drop down menu and type the code to specify the pathname.

(d) twip.

Explanation- In Java, size measurements are in twip. A twip is equal to 1/1440 of an inch.

(b)KeyListener.

Explanation- KeyListener is the listener interface for receiving keyboard events (keystrokes). If component want to process its own keystrokes, the easiest way is to implement the KeyListener interface.