IncdecApp3: Canvas.java

import java.awt.*;
import javax.swing.*;

/**
 * Need our own little class for the pie chart,
 * so it can catch paint callback and pass it back to parent
 */
public class Canvas extends JPanel {
    private IncdecPie parent;

    public Canvas (IncdecPie parent) {
	this.parent = parent;
	setPreferredSize (new Dimension (50, 50));
    }
    
    public void paintComponent (Graphics g) {
	super.paintComponent(g);
	parent.drawCanvas (g); //*1 Catch this and delegate to parent, it has the info
    }
}
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