Class MyCanvas2 

java.lang.Object
   |
   +----java.awt.Component
           |
           +----java.awt.Canvas
                   |
                   +----MyCanvas2
public class MyCanvas2
extends Canvas
implements ScrollReadable
To use the Scroller, a Canvas must be subclassed, and the subclass must implement the ScrollReadable interface.

Constructor Index

o MyCanvas2()

Method Index

o paint(Graphics)
The paint method creates and paints to the offscreen image.
o scrollDown()
This method draws the offscreen image on the canvas using the x, y positions which creates the scrolling effect.
o ScrollRead(float, float)
This method is called from the Scroller whenever the scrollbars are used, and changes the x/y positions of the offscreen image relative to the canvas for the offscreen image to scroll.
o update(Graphics)

Constructors

o MyCanvas2 
  public MyCanvas2()

Methods

o paint 
  public void paint(Graphics g)
The paint method creates and paints to the offscreen image.

Overrides:
paint in class Canvas
o scrollDown 
  public void scrollDown()
This method draws the offscreen image on the canvas using the x, y positions which creates the scrolling effect.

o update 
  public void update(Graphics g)
Overrides:
update in class Component
o ScrollRead 
  public void ScrollRead(float hpercentage,
                         float vpercentage)
This method is called from the Scroller whenever the scrollbars are used, and changes the x/y positions of the offscreen image relative to the canvas for the offscreen image to scroll. The width and height of the offscreen image is multiplied by the horiontal and vertical percentage (a float between 0 and 1)passed from the Scroller. The results are multiplied by -1 for the x and y position of the offscreen image. For example, if the vertical scrollbar is scrolled down 10%, then .10 is passed to this method in the vpercentage variable. To scroll the image 10% "upward", 10% of the offscreen image must be drawn above and out of view of the canvas allowing the rest of the 90% of the offecreen image to be viewed. To calculate the 10% that must be out of view, multiply the offscreen images height by .10, the result of this times -1 is where the y position of the offscreen image must start relative to the canvas.

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