Java II Course Study Notes: GUI

Java GUI

General info

AWT package
Swing package
Layout Manager

AWT package

Provides basic GUI components that are used in all Java applets and applications
Contains classes that can be extended and their properties inherited; classes can also be abstract.
Ensures that every GUI component that is displayed on the screen is a subclass of the abstract class Component

Panel 
Window
    Frame: add, setTitle, setSize, setLayout. BorderLayout

Components hierarchy

java.lang.Object
	
	BorderLayout
	CardLayout
	CheckboxGroup
	Color
	Dimension
	Event
	Font
	FlowLayout
	FontMetrics
	Graphics
	GridBagConstraints
	GridBagLayout
	GridLayout
	Image
	Insets
	Point
	Polygon
	Rectangle
	Toolkit
	MenuComponent
		MenuBar
		MenuItem
			Menu - PopupMenu
			CheckboxMenuItem
	Component
		Button
		Canvas
		Checkbox
		Choice
		Container
			Panel
				Applet
			Window
				Dialog
					FileDialog
				Frame
			ScrollPane
		Label
		List
		Scrollbar
		TextComponent
			TextArea
			TextField

set position in a container:
- setLocation(x,y)
- setSize(x,y)
- setBounds(x,y,width,height)

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Swing package

javax.swing.*;
Pluggable look and feel.
components: JButton, JFrame, JWindow, etc.
Light-weight compared with AWT package.

Components hierarchy.

java.awt.Container
	com.sun.java.swing.JComponent
		JTextComponent
			JTextArea
			JTextField
				JPasswordField
			HtmlEditorKit
		AbstractButton
			JToggleButton
				JCheckBox
				JRadioButton
			JButton
			JMenuItem
				JRadioButtonMenuItem
				JCheckBoxMenuItem
				JMenu
		JPanel
		JComboBox
		JLabel
		JLayeredPane
		JList
		JToolBar
		JMenuBar
		JPopupMenu
		JPanel
		JScrollBar
		JScrollPane
		JSlider
		JTable
		JSeparator
		JTree
		JProgressBar
		JRootPane

Swing application
- Importing Swing packages
- Choosing the look and feel: getLookAndFeel()
- Setting up a Window container.JFrame is similar to Frame
- Getting a container to add components. getContentPane().add(..);

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Container layout

FlowLayout, Panel, Applet
- Components added from left to right
- Default alignment is centered
- Uses components’ preferred sizes
- Use the constructor to tune behavior
BorderLayout, Frame, Window, Dialog
- arranging and resizing its components to fit in five regions:
  1. BorderLayout.NORTH
  2. BorderLayout.SOUTH
  3. BorderLayout.EAST
  4. BorderLayout.WEST
  5. BorderLayout.CENTER
- Each region may contain no more than one component
- Default is BorderLayout.CENTER
GridLayout
- Components are added left to right, top to bottom.
- All regions are equally sized.
- The constructor specifies the rows and columns.
CardLayout
- Only one card is visible at a time
- The container acts as a stack of cards
- The ordering is determined by the container's own internal ordering of its component objects
GridBagLayout
- Complex layout facilities can be placed in a grid.
- A single component can take its preferred size.
- A component can extend over more than one cell.

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