Class MyJFrame

java.lang.Object
  java.awt.Component
      java.awt.Container
          java.awt.Window
              java.awt.Frame
                  javax.swing.JFrame
                      MyJFrame

All Implemented Interfaces:

java.awt.event.ActionListener, java.awt.image.ImageObserver, java.awt.MenuContainer, java.io.Serializable, java.util.EventListener, javax.accessibility.Accessible, javax.swing.RootPaneContainer, javax.swing.WindowConstants

public class MyJFrame
extends javax.swing.JFrame
implements java.awt.event.ActionListener

Chapter 7 Basic GUI and Event Handling - Part II (Part I).
GUI objects such as buttons, text fields, labels and panels are placed on the content pane of a frame window. A frame has one JMenuBar object. A single JMenuBar can have many JMenu objects with many JMenuItem objects associated to a single JMenu object. While the variety of GUI objects may be extensive, the technique for nesting (adding) them to other objects is similar for each -for the content pane call its add method passing the object to be added as a parameter, likewise for the JMenuBar call its add method passing the menu to be added as a parameter, and to add menuItems to a menu just call the menu's add method passing the menuItem as a parameter. JMenuItems generate action events. In each case, the event source must register its event listener(s) so the system can pass the event object generated to the appropriate listener method.

Key Concepts:

1. Multiple reference variables can refer to the same object.
2. A wrapper class allows a primitive object to be managed as an object.
3. Containers are special GUI components that hold and organize other components.
4. A frame is displayed as a separate window, but a panel can only be displayed as part of another container.
5. A frame has a title bar and content pane.
6. To add a menu bar to the frame use the setJMenuBar and add methods.
7. Every container is managed by a layout manager, to override this call setLayout passing it null.
8. Panels can be nested to create an intricate containment hierarchy of components.
9. A label or button can contain text, an image, or both.

Right-click Save File As... => Source Code splat.gif computer.jpg
Another example from the Sun Java Tutorial: JButton.zip

Author:

Jack Tompkins

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class javax.swing.JFrame

javax.swing.JFrame.AccessibleJFrame

Nested classes/interfaces inherited from class java.awt.Frame

java.awt.Frame.AccessibleAWTFrame

Nested classes/interfaces inherited from class java.awt.Window

java.awt.Window.AccessibleAWTWindow

Nested classes/interfaces inherited from class java.awt.Container

java.awt.Container.AccessibleAWTContainer

Nested classes/interfaces inherited from class java.awt.Component

java.awt.Component.AccessibleAWTComponent, java.awt.Component.BltBufferStrategy, java.awt.Component.FlipBufferStrategy

Field Summary

private javax.swing.JButton	anotherButton
private int	anotherButtonCount
private javax.swing.JButton	button
private int	buttonCount
private javax.swing.JTextField	inputLine
private javax.swing.JLabel	label

Fields inherited from class javax.swing.JFrame

accessibleContext, EXIT_ON_CLOSE, rootPane, rootPaneCheckingEnabled

Fields inherited from class java.awt.Frame

CROSSHAIR_CURSOR, DEFAULT_CURSOR, E_RESIZE_CURSOR, HAND_CURSOR, ICONIFIED, MAXIMIZED_BOTH, MAXIMIZED_HORIZ, MAXIMIZED_VERT, MOVE_CURSOR, N_RESIZE_CURSOR, NE_RESIZE_CURSOR, NORMAL, NW_RESIZE_CURSOR, S_RESIZE_CURSOR, SE_RESIZE_CURSOR, SW_RESIZE_CURSOR, TEXT_CURSOR, W_RESIZE_CURSOR, WAIT_CURSOR

Fields inherited from class java.awt.Component

BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields inherited from interface javax.swing.WindowConstants

DISPOSE_ON_CLOSE, DO_NOTHING_ON_CLOSE, HIDE_ON_CLOSE

Fields inherited from interface java.awt.image.ImageObserver

ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH

Constructor Summary

MyJFrame()
Set the title bar contents, set the size, set the default close operation, get the content pane and set its properties, set the JMenuBar and add menu(s) to it.

Method Summary

void	actionPerformed(java.awt.event.ActionEvent event) Determine which source generated the event.
static void	main(java.lang.String[] args)
void	processJMenuItem(java.lang.String command) Process the menu.
void	processJTextField(java.lang.String text) Process the text field.

Methods inherited from class javax.swing.JFrame

addImpl, createRootPane, frameInit, getAccessibleContext, getContentPane, getDefaultCloseOperation, getGlassPane, getJMenuBar, getLayeredPane, getRootPane, isDefaultLookAndFeelDecorated, isRootPaneCheckingEnabled, paramString, processWindowEvent, remove, setContentPane, setDefaultCloseOperation, setDefaultLookAndFeelDecorated, setGlassPane, setIconImage, setJMenuBar, setLayeredPane, setLayout, setRootPane, setRootPaneCheckingEnabled, update

Methods inherited from class java.awt.Frame

addNotify, finalize, getCursorType, getExtendedState, getFrames, getIconImage, getMaximizedBounds, getMenuBar, getState, getTitle, isResizable, isUndecorated, remove, removeNotify, setCursor, setExtendedState, setMaximizedBounds, setMenuBar, setResizable, setState, setTitle, setUndecorated

Methods inherited from class java.awt.Window

addPropertyChangeListener, addPropertyChangeListener, addWindowFocusListener, addWindowListener, addWindowStateListener, applyResourceBundle, applyResourceBundle, createBufferStrategy, createBufferStrategy, dispose, getBufferStrategy, getFocusableWindowState, getFocusCycleRootAncestor, getFocusOwner, getFocusTraversalKeys, getGraphicsConfiguration, getInputContext, getListeners, getLocale, getMostRecentFocusOwner, getOwnedWindows, getOwner, getToolkit, getWarningString, getWindowFocusListeners, getWindowListeners, getWindowStateListeners, hide, isActive, isAlwaysOnTop, isFocusableWindow, isFocusCycleRoot, isFocused, isLocationByPlatform, isShowing, pack, postEvent, processEvent, processWindowFocusEvent, processWindowStateEvent, removeWindowFocusListener, removeWindowListener, removeWindowStateListener, setAlwaysOnTop, setBounds, setCursor, setFocusableWindowState, setFocusCycleRoot, setLocationByPlatform, setLocationRelativeTo, show, toBack, toFront

Methods inherited from class java.awt.Container

add, add, add, add, add, addContainerListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getAlignmentX, getAlignmentY, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getComponentZOrder, getContainerListeners, getFocusTraversalPolicy, getInsets, getLayout, getMaximumSize, getMinimumSize, getMousePosition, getPreferredSize, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paint, paintComponents, preferredSize, print, printComponents, processContainerEvent, remove, removeAll, removeContainerListener, setComponentZOrder, setFocusTraversalKeys, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setFont, transferFocusBackward, transferFocusDownCycle, validate, validateTree

Methods inherited from class java.awt.Component

action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, createVolatileImage, createVolatileImage, disable, disableEvents, dispatchEvent, enable, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBounds, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getFontMetrics, getForeground, getGraphics, getHeight, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocation, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPeer, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getSize, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isDoubleBuffered, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isOpaque, isPreferredSizeSet, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, prepareImage, prepareImage, printAll, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, processMouseWheelEvent, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, reshape, resize, resize, setBackground, setBounds, setComponentOrientation, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeysEnabled, setForeground, setIgnoreRepaint, setLocale, setLocation, setLocation, setMaximumSize, setMinimumSize, setName, setPreferredSize, setSize, setSize, setVisible, show, size, toString, transferFocus, transferFocusUpCycle

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.awt.MenuContainer

getFont, postEvent

Field Detail

button

private javax.swing.JButton button

anotherButton

private javax.swing.JButton anotherButton

buttonCount

private int buttonCount

inputLine

private javax.swing.JTextField inputLine

label

private javax.swing.JLabel label

anotherButtonCount

private int anotherButtonCount

Constructor Detail

MyJFrame

public MyJFrame()

Set the title bar contents, set the size, set the default close operation, get the content pane and set its properties, set the JMenuBar and add menu(s) to it.

• Set layout
• Set background

Create buttons

• Set bounds
• Register action listener
• Add to content pane

Create text field

• Set bounds
• Register action listener
• Add to content pane

Set JMenu Bar

• Add menu items to menu
• Register action listener with menu items
• Add menu to menu bar

Create label

• Set bounds
• Add to content pane

Method Detail

main

public static void main(java.lang.String[] args)

actionPerformed

public void actionPerformed(java.awt.event.ActionEvent event)

Determine which source generated the event. If it was a button, distinguish between the two buttons and increment the respective button counter and button text. If the event source was an menu item, get the action command and pass the command to the processJMenuItem method. If the event source was the text field, pass the text to the processJTextField method.

Specified by:

actionPerformed in interface java.awt.event.ActionListener

Parameters:

event - generated by one of the three menu items, two buttons, or the text field.

processJMenuItem

public void processJMenuItem(java.lang.String command)

Process the menu. If the menu command is "Clear Buttons" assign 0 to both button counters and set the respective button text to the counter values. If the command is "Quit" call System exit. Otherwise the third command generated the event and the bottom button has its text set to the hexadecimal value of the top button.

Parameters:

command - the text in the menu item ("Clear Buttons", "Quit", ...)

processJTextField

public void processJTextField(java.lang.String text)

Process the text field. If the text field is empty increment the top button. If the text field has a number, convert the string and assign it to the button counter and update the button text. If the text field contains a hexidecimal number, convert the string to decimal and assign it to the button counter and update the button text.

Parameters:

text - the text from the input line.