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1. Generic (JComponent) services2. Atomic Swing components3. Containers4. Drawing primitives

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Component ServicesAll (?) Swing-components, except top-level containers, inherit from JComponent, Container and Component

Main services

Customizing Component Appearance

Setting Component State

• get/set foreground/background colour• get/set font• get/set border• specify/get opaqueness

• setting tooltips• (in)activate component• control visibility

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Component Services

Handling Events

Painting Components

Containment Hierarchy

• (de)registration of event listeners• check if pixel is part of component• check to which component pixel belongs

• repaint() : request to repaint the components• revalidate() : request to lay out again component• paintComponent() : overridden method for custom drawing

• add/remove components from container• get contained components in container

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Component Services

Laying Out Components• get/set preferred, maximum and minimum sizes• get set alignment mode• get/set layoutmanager

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Examples :Setting Tooltips

JComponent :void setToolTipText(String)

class ToolTip extends JFrame {JButton change = new JButton("Switch");ToolTip(String title) {

super(title);Container cp=getContentPane();cp.setLayout(new FlowLayout());change.setToolTipText("Press to switch");cp.add(change);

}}

public class TooltipTest { public static void main(String[] args) { ToolTip app=new ToolTip("Setting tooltips"); app.setSize(200,100); app.setVisible(true);

app.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); }}

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Examples :Controlling Look and Feel

Look and feel options• swing : default

or : getCrossPlatformLookAndFeelClassName()• motif : “com.sun.java.swing.plaf.motif.MotifLookAndFeel”• system : getSystemLookAndFeelClassName()

Format try {

UIManager.setLookAndFeel( ……);} catch(Exception e) { }

• before instantiating visible components• don’t change L&F during program execution ! (possible but difficult)

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Examples :Controlling Look and Feel

class LF extends JFrame {JButton change = new JButton("Switch");LF(String title) {

super(title);Container cp=getContentPane();cp.setLayout(new FlowLayout());change.setToolTipText("Press to switch");cp.add(change);

}} public class LookAndFeelTest {

public static void main(String[] args) { try { // UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); UIManager.setLookAndFeel("com.sun.java.swing.plaf.motif.MotifLookAndFeel"); } catch(Exception e) { } LF app=new LF("Trying different L&F's"); app.setSize(200,100); app.setVisible(true); app.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); }}

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Examples :Adding Borders

Types of borders• TitledBorder• EtchedBorder• EmptyBorder• BevelBorder• LineBorder• SoftBevelBorder• MatteBorder• CompoundBorder

How ?• Construct a Border-object• invoke setBorder(…) on the relevant JComponent

Inherit from AbstractBorder,Implementing the Border interface

import javax.swing.border.*;

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Examples :Adding Borders

class BorderT extends JFrame {private static int num=5;private JButton[] b=new JButton[num];public BorderT(String title) {

super(title);for(int i=0;i<b.length;i++) {

b[i]=new JButton("Button "+i);}b[1].setBorder(new TitledBorder("Border Title"));b[2].setBorder(new EtchedBorder());b[3].setBorder(new LineBorder(Color.red));b[4].setBorder(new BevelBorder(BevelBorder.RAISED));getContentPane().setLayout(new FlowLayout());for(int i=0;i<b.length;i++)

getContentPane().add(b[i]);

}} // End of class BorderT

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Binary choices

No state

State

JButton

JToggleButtonJRadioButtonJCheckBox

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Multivalued choices

>1 alternative

1 alternative at most

• JList• list of buttons• JMenu

• JList (after setting seletion mode)• JComboBox• list of buttons added to ButtonGroup• JMenu (JRadioButtonMenuItem, JCheckBoxMenuItem)

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Multivalued choices

JList JMenu

JComboBox (non-editable) JComboBox (editable)

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Multivalued choices

“continuous” value

JSlider

Fires ChangeEvents when value changes

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Multivalued choicesclass SliderT extends JFrame {

private JSlider s=new JSlider(0,100,70);private JLabel output=new JLabel("Value = 70");public SliderT(String title) {

super(title);Container cp=getContentPane();s.setPaintTicks(true);s.setMinorTickSpacing(5);s.setMajorTickSpacing(20);cp.setLayout(new GridLayout(2,1));cp.add(s);cp.add(output);ChangeListener c=new ChangeListener() {

public void stateChanged(ChangeEvent e) {output.setText("Value = "+s.getValue());

}};s.addChangeListener(c);

}} // End of class SliderT

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Text

1 line

• JTextField

>= 1 line

• JTextArea (plain text) • JEditorPane (styled text)• JTextPane (styled text)

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Text

JTextArea

JTextPane

• several styles• embedded pictures• displays HTML

[Sun, Swing Tutorial]

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Output only ...

• JLabel• JProgressBar

• Tool tips

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Output only ...class ProgressT extends JFrame {

private JProgressBar pb=new JProgressBar(0,20);private JButton start=new JButton("(Re)Start");private JButton next=new JButton("Next");private int count=0;public ProgressT(String title) {

super(title);Container cp=getContentPane();cp.setLayout(new GridLayout(3,1));cp.add(pb);cp.add(next);cp.add(start);pb.setStringPainted(true);next.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e){

pb.setValue(++count);if(count==20) next.setEnabled(false); }});start.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent e){

count=0;pb.setValue(0);next.setEnabled(true); }});

}} // End of class ProgressT

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Formatted Information

• JColorChooser

• getColor returns color choosen

• class can createdialog

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Formatted Information

• JColorChooser

class ColorT extends JFrame {private JColorChooser cc=new JColorChooser();public ColorT(String title) {

super(title);Container cp=getContentPane();cp.add(cc,BorderLayout.CENTER);

}} // End of class ColorT

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Formatted Information

• JFileChooser

• JTable • JTree

[Sun, Swing Tutorial]

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Intermediate Containers

• JPanel

• used to group components• behavior inherited from Container

• LayoutManager• methods to add/remove Jcomponents

• invisible by default

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Intermediate Containers class PanelT extends JFrame {

private JPanel left=new JPanel();private JPanel right=new JPanel();public PanelT(String title) {

super(title);Container cp=getContentPane();cp.setLayout(new GridLayout(1,2));left.setLayout(new GridLayout(3,1));right.setLayout(new GridLayout(3,1));left.setBorder(new TitledBorder("Left Panel"));right.setBorder(new TitledBorder("Right Panel"));

left.add(new JButton("A"));left.add(new JSlider(0,100,75));left.add(new JCheckBox("Check me ..."));

cp.add(left);right.add(new JToggleButton("B"));right.add(new JProgressBar(0,100));right.add(new JRadioButton("Click me ..."));

cp.add(right);}

} // End of class PanelT

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Intermediate Containers

• JScrollPane

Adds scroll bars (if needed) to any JComponent

…JScrollPane scrollLeft=new JScrollPane(left);cp.add(scrollLeft);...

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Intermediate Containers

• JTabbedPane

Used to realize hierarchy andsave space

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Intermediate Containersclass TabbedPaneT extends JFrame {

private JPanel left=new JPanel();private JPanel right=new JPanel();public TabbedPaneT(String title) {

super(title);Container cp=getContentPane();JTabbedPane tp=new JTabbedPane();

left.setLayout(new GridLayout(3,1));right.setLayout(new GridLayout(3,1));left.add(new JButton("A"));left.add(new JSlider(0,100,75));left.add(new JCheckBox("Check me ..."));right.add(new JToggleButton("B"));right.add(new JProgressBar(0,100));right.add(new JRadioButton("Click me ..."));

tp.addTab("Left",left);tp.addTab("Right",right);cp.add(tp);

}} // End of class TabbedPaneT

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Intermediate Containers

• JSplitPane

Used to divide area in 2, allowing splittingratio to vary

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Intermediate Containersclass SplitPaneT extends JFrame {

private JPanel left=new JPanel();private JPanel right=new JPanel();public SplitPaneT(String title) {

super(title);Container cp=getContentPane();

left.setLayout(new GridLayout(3,1));right.setLayout(new GridLayout(3,1));left.add(new JButton("A"));left.add(new JSlider(0,100,75));left.add(new JCheckBox("Check me ..."));right.add(new JToggleButton("B"));right.add(new JProgressBar(0,100));right.add(new JRadioButton("Click me ..."));JSplitPane sp=new JSplitPane(

JSplitPane.HORIZONTAL_SPLIT,left,right);sp.setOneTouchExpandable(true);

cp.add(sp);}

} // End of class SplitPaneT

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Intermediate Containers

• JToolBarGraphical presentation of menuIcon based

[Sun, Swing Tutorial]

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Top-level Containers

• JFrame-> Base class for stand alone applications

• JApplet-> Base class for applets

• JDialog-> Can pop up from other Container-> no exit when Dialog closes

Can have menu bars

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Concept

• every JComponent has a paintComponent method responsible of drawing the component on the screen• paintComponent is automatically called by container object

In practice(1) define a class extending JPanel(2) define a drawing method with signature

public void paintComponent(Graphics g) {super.paintComponent(g);// drawing operations

}(3) make an object of this class, and add it to some container

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Graphical Context

“physical” area where component can be painted

(0,0)

(0,200) (500,200)

(500,0)

pixel (“picture element”)

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Drawing Primitives

Pen Color

Operations

• public void setColor(Color c) • public Color getColor()

(x1,y1)

(x2,y2)

g.drawLine(x1,y1,x2,y2);

g.setColor(Color.green);

• public abstract void drawLine(int x1, int y1, int x2, int y2)

Graphics object

Lines

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Drawing Primitives

Rectangles

(x1,y1)b

h

g.drawRect(x1,y1,b,h);

g.fillRect(x1,y1,b,h);

• public abstract void drawRect(int x1, int y1, int b, int h)• public abstract void fillRect(int x1, int y1, int b, int h)

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Drawing Primitives

Ovals

(x1,y1)b

h

g.drawOval(x1,y1,b,h);

g.fillOval(x1,y1,b,h);

• public abstract void drawOval(int x1, int y1, int b, int h)• public abstract void fillOval(int x1, int y1, int b, int h)

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Drawing Primitives

Arcs

(x1,y1) b

h

g.drawArc(x1,y1,b,h,s,a);

g.fillArc(x1,y1,b,h,s,a);

• public abstract void drawArc(int x1, int y1, int b, int h,int s, int a)• public abstract void fillArc(int x1, int y1, int b, int h,int s, int a)

sa

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Drawing PrimitivesPolygons

(x[0],y[0])(x[2],y[2])

(x[1],y[1])

(x[3],y[3])g.drawPolyline(x,y,4);

g.drawPolygon(x,y,4);

g.fillPolygon(x,y,4);

• public abstract void drawPolyline(int[] x, int[] y, int n)• public abstract void drawPolygon(int[] x, int[] y, int n)• public abstract void fillPPolygon(int[] x, int[]y, int n)

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Example class MyDrawing extends JPanel {

public void paintComponent(Graphics g) {super.paintComponent(g);g.setColor(Color.red);g.drawLine(0,0,100,100);g.setColor(Color.blue);g.drawOval(50,50,150,150);

}} // End of class MyDrawing

class DrawingT extends JFrame {private MyDrawing d=new MyDrawing();public DrawingT(String title) {

super(title);Container cp=getContentPane();cp.add(d);

}} // End of class DrawingT

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Drawing Primitives

Text

Font • public void setFont(Font f) • public Font getFont()

Draw

(x,y)

g.drawString(“Message”,x,y);

Message

• public abstract void drawString(String s, int x, int y)

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Specifying FontsFont characteristics

type

style

size

Options :• Dialog• DialogInput• Monospaced• Serif• SansSerif• Symbol

PLAINBOLDITALIC

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Specifying Fonts

Constructor

• public Font(String name, int style, int size)

Examples

Font f1 = new Font(“Dialog”,Font.PLAIN,10);Font f2 = new Font(“Serif”, Font.BOLD, 14);Font f3 = new Font(“Dialog”,Font.BOLD||Font.ITALIC, 20);