JFrame vs Graphics

1
JFrame vs Graphics
2
Color class

• Like the String class, and Integer class, does
  not use the new keyword.
• holds a color value (nothing more)
• e.g Color boxColor new Color( )
• boxColor Color.blue
• or
• Color boxColor Color.blue
• then boxColor can be used to set System
  properties in Classes/Objects that need color
  (more later).

3
JColorChooser returns a Color object to the
caller
4
Returns an Object?

• JColorChooser fills in all of the information in
  a blank object of the Color class, and copies it
  to the Color object in the calling statement
• boxColor JColorChooser.showDialog(
• null, Greeting, default color )

5
Font

• Defined (needs constructor info)
• Font myFont new Font( Arial, Font.PLAIN, 12)
• Used
• g.setFont( myFont )
• g.setColor( Color.red)
• g.drawString( hello" ,160, 220)

Type
Style
Size
6
Polygon

• Defined
• int xValues 20, 40, 50, 30, 20, 15
• int yValues 50, 50, 60, 80, 80, 60
• Polygon shape1
• new Polygon( xValues, yValues, 6 )
• Used
• g.drawPolygon( shape1 )

Number of points
7
Graphics method summary

• paint (Graphics g)
• g.setColor( boxColor )
• g.fillArc( x, y, width, height, 0, 360 )
• g.fillRect( x, y, width, height )
• g.setFont( myFont )
• g.drawString( hello" ,160, 220 )
• g.drawPolygon( shape1 )
• g.drawLine( x1,y1,x2,y2)

8
A push-button object

• JButton helloButton new JButton( "Hello" )
• Where can we place the pushbutton?
• On anything, really remember that!

9

• import javax.swing.
• import java.awt.
• public class Button extends JFrame
• public Button()
• setSize(400,400)
• JButton myButton new JButton(push")
• add( myButton)
• setVisible(true)
• public static void main(String args )
• Button app new Button()
• // end class

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JFrame methods summary

• setSize (400, 400)
• setLocation (50, 75)
• add( someObject )
• setDefaultCloseOperation( EXIT_ON_CLOSE )
• setVisible( true )

11
the JFrame layouts and panels

• Holds a whole window context frames, scroll
  bars, buttons, menus, pop-ups, and operator
  actions mouse clicks, dragging dropping.
• Operator actions are called events.
• "Controls" can be added to a frame.
• JFrames are a type of Container.

12
A Container manages all PC resources

• Its brilliant, really

JFrame and other Containers
Layout presentation
Events operator actions
Container
13
what does this do?

• setLayout( new FlowLayout( ) )

14
more JFrame methods

• setSize( w, h )
• setLocation( x, y )
• setDefaultCloseOperation( EXIT_ON_CLOSE )
  
• setLayout( new FlowLayout( ) )
• JButton helloButton new JButton( "Hello" )
• add( helloButton )
• setVisible( true )