Introduction to Sing Components
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| UI(User Interface) Components | Buttons, text fields, and other components with which the user can interact. Also called controls or widgets
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| Swing Components | UI elements such as dialog boxes and buttons; you can usually recognize their names because they begin with J
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| Java Foundation Classes(JFC) | A more general set of UI programming capabilities. JFC includes Swing component classes and selected classes from the java.awt package
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| Lightweight Components | Almost all Swing components are said to be lightweight components because they are written completely in Java and do not have to rely on the local operating system code
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| Heavyweight Components | Some Swing components, such as JFrames, are known as heavyweight components because they do require interaction with the local operating system
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| Container | A type of component that holds other components so you can treat a group of them as a single entity
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| 1. Method Inherited by the JFrame Class | 1. Method[void setTitle(String)]..Purpose[Sets a JFrame's title using the String argument]...
2. Method[void setSize(int, int)]..Purpose[Sets a JFrame's size in pixels with the width and height as arguments]...
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| 2. Method Inherited by the JFrame Class | 3. Method[void setSize(Dimension)]..Purpose[Sets a JFrame's size using Dimension class object: the Dimension(int, int) constructor creates an object that represents both a width and height]...
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| 3. Method Inherited by the JFrame Class | 4. Method[String getTitle()]..Purpose[Returns a JFrame's title]...
5. Method[void setResizble(boolean)]..Purpose[Sets the JFrame to be resizable by passing true to the method, or sets the JFrame not to be resizable by passing false to the method]....
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| 4. Method Inherited by the JFrame Class | 6. Method[boolean isResizable()]..Purpose[Returns true or false to indicate whether JFrame is resizable]...
7. Method[void setVisible(boolean)]..Purpose[Sets JFrame to be visible using boolean argument true and invisible using boolean argument false]...
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| 5. Method Inherited by the JFrame Class | 8. Method[void setBounds(int, int, int, int)]..Purpose[Overrides the default behavior for the JFrame to be positioned in the upper-left corner or computer screen.
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| 6. Method Inherited by the JFrame Class | First two arguments are horizontal and vertical positions or JFrame's upper-left corner on desktop. Final two arguments set width and height.]
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| Pixels | The picture elements, or tiny dots of light, that make up the image on your computer monitor
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| Look and Feel | The default appearance and behavior of any user interface. You can request that Java's look and feel provide the decorations for the frame
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| JLabel | A built-in Java Swing class that holds text you can display
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| add() Method | You can add JLabel and other object to a JFrame object using this method. Ex: JLabel greeting = new Label("Good day");...
aFrame.add(greeting);...
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| remove() Method | Counterpart to the add() method. Removes object from a JFrame. Ex: aFrame.remove(greeting);
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| setText() Method | Can be used to change the text in a JLabel by using this Component class method with the JLabel object and passing a String to it. Ex: greeting.setText("Howdy");
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| getText() Method | Used to retrieve the text in a JLabel(or other Component) by using this method, which returns the currently stored String
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| Font Class | A Java provided class from which you can create an object that holds typeface and size information.
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| setFont() Method | Requires a Font object argument. To construct a Font object, you need three arguments: typeface, style, and point size.
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| Typeface Argument | The typeface argument to the Font constructor is a String representing a font. Common fonts have names such as Arial, Century, Monospaced, and Times New Roman.
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| Style Argument | Applies an attribute to displayed text and is one of three values: Font.PLAIN, Font.BOLD, or Font.ITALIC
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| Point Size Argument | An integer that represents about 1/72 of an inch. Printed text is commonly 12 points; a headline might be 30 points
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| 1. Giving a JLabel Object New Font | To give a JLabel object a new font, you can create a FOnt object, as in the following...
Font headlineFont = new Font("Monospaced", Font.Bold, 36);. The Typeface name is a String, so you must enclose it in double quotation marks.
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| 2. Giving a JLabel Object New Font | You can use the setFont() method to assign the Font to a JLabel with a statement such as...
greeting.setFont(headlineFont);
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| Layout Manager | To place multiple components at specified positions in a container so they do not hide each other, you must explicitly use a layout manager - a class that controls component positioning. Normal behavior of a JFrame is to use layout format BorderLayout
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| BorderLayout | Created by using BorderLayout class. Divides a container into regions. When you do not specify a region in which to place a component, all the components are placed in the same region, and they obscure each other
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| Flow Layout Manager | Places components in a row, and when a row is filled, components automatically spill into the next row
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| FlowLayout Class Three Constants | Specify how components are positioned in each row of their container. These constants are FlowLayout.LEFT, FlowLayout.RIGHT, and FlowLayout.CENTER. Ex: FlowLayout flow = new FlowLayout(FlowLayout.RIGHT);
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| setLayout() Method | Sets a JFrame's layout. Ex: aFrame.setLayout(flow);. A more compact syntax that uses an anonymous FlowLayout object is...
aFrame.setLayout(new FlowLayout());
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| JTextField | A component into which a user can type a single line of text data. Text data comprises any characters you can enter from the keyboard, including numbers and punctuation
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| Instantiating a JTextField Object | To provide a JTextField that allows enough room for a user to enter approximately 10 characters, you can code the following..
JTextField response = new JTextField(10);...
To add the JTextField response to JFrame frame, you write..
frame.add(response);
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| Editable JTextFields | A JTextField is editable when it has the capability of accepting keystrokes. A JTextField is editable by default
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| setEditable() Method | If you do not want the user to be able to enter data in a JTextField, you can send a Boolean value to this method to change the JTextField's editable status
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| JButton | A Component the user can click with a mouse to make a selection
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| Tool Tips | Popup windows that can help a user understand the purpose of components in an applications; the tool tip appears when a user hovers the mouse pointer over the component
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| setToolTipText() Method | Used to define the text to be displayed in a tool tip by passing an appropriate String to it. Ex: button.setToolTipText("Click this button");
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| Event | Occurs when a user takes action on a component, such as clicking the mouse on a JButton object
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| Event-Driven Program | A program in which the user might initiate any number of events in any order
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| Source of Event | Within an event-driven program, a component on which an event is generated is the source of the event
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| Listener | An object that is interested in an event
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| addActionListener() Method | Used to tell your class to expectnActionEvents
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| Preparing Your Class to Accept Event Messages | You prepare your class to accept button button press events by importing the java.awt.event package into your program and adding the phrase implements ActionListener to the class header
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| java.awt.event Package | Includes event classes with names such as ActionEvent, ComponentEvent, and TextEvent.
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| ActionListener | Is an interface - a class containing a set of specifications for methods that you can use. Implementing ActionListener provides you with standard event method specifications that allow your listener to work with ActionEvent
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| ActionEvents | The types of events that occur when a user clicks a button
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| actionPerformed(ActionEvent e) Method | When a class =, such as a JFrame , has a registered as a listener with a Component such as a JButton, and a user clicks the JButton, the actionPerformed() method executes. The ActionLIstener interface contains this method
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| 1. Responding to Events | You use the following header, in which e represents any name you choose for the Event(the JButton click) that intiated the notification of the ActionListener(which is the JFrame)...
public void actionPerformed(ActionEvent e).
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| 2. Responding to Events | The body of the method contains any statements that you want to execute when the action occurs
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| setEnabled() Method | Used to make a component available or unavailable by passing true or false to it, respectively
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| 1. Alphabetical List of Some Event Listeners | 1. Listener[ActionListener]..TypeOfEvents[Action events]..Ex[Button clicks]...
2. Listener[AdjustmentListener]..TypeOfEvents[Adjustment events]..Ex[Scroll bar moves]...
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| 2. Alphabetical List of Some Event Listeners | 3. Listener[ChangeListener]..TypeOfEvents[Change events]..Ex[Slider is repositioned]...
4. Listener[FocusListener]..TypeOfEvents[Keyboard focus events]..Ex[Text field grains or loses focus]...
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| 3. Alphabetical List of Some Event Listeners | 5. Listener[ItemListener]..TypeOfEvents[Item events]..Ex[Check box changes status]...
6. Listener[KeyListener]..TypeOfEvents[Keyboard events]..Ex[Text is entered]...
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| 4. Alphabetical List of Some Event Listeners | 7. Listener[MouseListener]..TypeOfEvents[Mouse events]..Ex[Mouse clicks]...
8. Listener[MouseMotionListener]..TypeOfEvents[Mouse movement events]..Ex[Mouse rolls]...
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| 5. Alphabetical List of Some Event Listeners | 9. Listener[WindowListener]..TypeOfEvents[Window events]..Ex[Window closes]
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| 1. Some Swing Components and Their Associated Listener-Registering Methods | 1. Components[JButton, JCheckBox, JComboBox, JTextField, and JRadioButton]..AssociatedListenerRegisteringMethods[addActionListener()]...
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| 2. Some Swing Components and Their Associated Listener-Registering Methods | 2. Components[JScrollBar]..AssociatedListenerRegisteringMethods[addAdjustmentListener()]...
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| 3. Some Swing Components and Their Associated Listener-Registering Methods | 3. Components[All Swing components]..AssociatedListenerRegisteringMethods[addFocusListener(), addKeyListener(), addMouseListener(), and addMouseMotionListener()]...
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| 4. Some Swing Components and Their Associated Listener-Registering Methods | 4. Components[JButton, JCheckBox, JComboBox, and JRadioButton]..AssociatedListenerRegisteringMethods[addItemListener()]...
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| 5. Some Swing Components and Their Associated Listener-Registering Methods | 5. Components[All JWindow and JFrame components]..AssociatedListenerRegisteringMethods[addWindowListener()]...
6. Components[JSlider and JCheckBox]..AssociatedListenerRegisteringMethods[addChangeListener())]
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| Event Handler | A method that executes because it is called automatically when an appropriate event occurs
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| 1. Selected Methods that Respond to Events | 1. Listener[ActionListener]..Method[actionPerformed(ActionEvent)]...
2. Listener[AdjustmentListener]..Method[adjustmentValueChanged(AdjustmentsEvent)]...
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| 2. Selected Methods that Respond to Events | 3. Listener[FocusListener]..Method[focusGained(FocusEvent) and focusLost(FocusEvent)]...
4. Listener[ItemListener]..Method[itemStatedChanged(ItemEvent)]
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| JCheckBox | Consists of a label positioned beside a square; you can click the square to display or remove a check mark
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| ButtonGroup Class | When you create a ButtonGroup, you can group several components, such as JCheckBoxes, so a user can select only one at a time
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| JComboBox | A component that combines two features: a display area showing a default option and list box that contains additional, alternate options
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| Generic Programming | A feature of modern languages that allows multiple data types to be used safely with methods.
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