| AquamaN |
03-26-2006 02:15 PM |
Java - Questions
Ok, I'm strayed from Obj-C, C/C++ and am trying out Java now. I have run into some trouble with my KeyListener as my simple program is not changing my modes (from polygon to circle).
Draw.java
Code:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Draw extends JApplet implements KeyListener
{
Display canvas;
public void init()
{
canvas = new Display();
setContentPane(canvas);
}
public char mode = 'c';
public void keyTyped(KeyEvent evt)
{
char ch = evt.getKeyChar();
if (ch == 'p' || ch == 'P')
mode = 'p';
else if (ch == 'c' || ch == 'C')
mode = 'c';
else if (ch == 'b' || ch == 'B')
mode = 'b';
}
public void keyPressed(KeyEvent evt) {}
public void keyReleased(KeyEvent evt) {}
class Display extends JPanel implements MouseListener
{
/* Variables for implementing polygon input. */
private int[] xCoord, yCoord; // Arrays containing the points of
// the polygon. Up to 500 points
// are allowed.
private int pointCt; // The number of points that have been input.
private Color polygonColor = Color.red;
// Color that is used to draw the polygons.
private Color theColor = Color.red;
public Display()
{
setBackground(Color.white);
addMouseListener(this);
xCoord = new int[500];
yCoord = new int[500];
pointCt = 0;
}
public void paintComponent(Graphics g)
{
super.paintComponent(g); // Fills with background color, white.
g.setColor(Color.black);
g.drawRect(0, 0, getWidth() - 1, getHeight() - 1);
g.drawRect(1, 1, getWidth() - 3, getHeight() - 3);
g.drawLine(35, 0, 35, 250);
g.setColor(Color.black);
g.fillRect(0, 0, 35, 50);
g.setColor(Color.blue);
g.fillRect(0, 50, 35, 100);
g.setColor(Color.red);
g.fillRect(0, 100, 35, 150);
g.setColor(Color.yellow);
g.fillRect(0, 150, 35, 200);
g.setColor(Color.green);
g.fillRect(0, 200, 35, 250);
}
private void putLine(int x1, int y1, int x2, int y2)
{
Graphics g = getGraphics();
g.drawLine(x1,y1,x2,y2);
g.dispose();
}
private void drawACircle (int x1, int y1, int x2, int y2)
{
Graphics g = getGraphics();
int dx, dy;
dx = Math.abs(x1 - x2);
dy = Math.abs(y1 - y2);
double radius = Math.sqrt((dx * dx) + (dy * dy));
g.setColor(theColor);
g.fillOval(x1, y1, (int)radius, (int)radius);
g.dispose();
}
private void putPolygon()
{
if (pointCt < 2)
return;
Graphics g = getGraphics();
if (pointCt == 2)
{
g.drawLine(xCoord[0], yCoord[0], xCoord[1], yCoord[1]);
}
else
{
g.setColor(theColor);
g.fillPolygon(xCoord, yCoord, pointCt);
g.setColor(Color.black);
g.drawPolygon(xCoord, yCoord, pointCt);
}
g.dispose();
}
public void mousePressed(MouseEvent evt)
{
if (evt.isShiftDown())
{
pointCt = 0;
repaint();
}
else if ( pointCt > 0 && (Math.abs(xCoord[0] - evt.getX())<=2) && (Math.abs(yCoord[0] - evt.getY())<=2) && mode == 'p' )
{
putPolygon();
pointCt = 0;
}
else if (evt.isMetaDown() || pointCt == 500)
{
putPolygon();
pointCt = 0;
}
else
{
if (mode == 'p')
{
xCoord[pointCt] = evt.getX();
yCoord[pointCt] = evt.getY();
//Get color to be used
if (evt.getX() <= 25)
{
if (evt.getY() <= 50)
theColor = Color.black;
else if (evt.getY() <= 100)
theColor = Color.blue;
else if (evt.getY() <= 150)
theColor = Color.red;
else if (evt.getY() <= 200)
theColor = Color.yellow;
else if (evt.getY() <= 250)
theColor = Color.green;
pointCt--;
}
pointCt++;
if (pointCt >= 2 && evt.getX() > 25)
{
putLine(xCoord[pointCt-2], yCoord[pointCt-2], xCoord[pointCt-1], yCoord[pointCt-1]);
}
}// end if 'p'
if (mode == 'c') //Circle Mode
{
xCoord[pointCt] = evt.getX();
yCoord[pointCt] = evt.getY();
if (evt.getX() <= 25)
{
if (evt.getY() <= 50)
theColor = Color.black;
else if (evt.getY() <= 100)
theColor = Color.blue;
else if (evt.getY() <= 150)
theColor = Color.red;
else if (evt.getY() <= 200)
theColor = Color.yellow;
else if (evt.getY() <= 250)
theColor = Color.green;
}
pointCt++;
if (pointCt >= 2 && evt.getX() > 25)
{
drawACircle(xCoord[pointCt-1], yCoord[pointCt-1], xCoord[pointCt], yCoord[pointCt]);
pointCt = 0;
}
}//end mode 'c'
} //end else
canvas.requestFocus();
} // end mousePressed()
public void mouseReleased(MouseEvent evt) { }
public void mouseClicked(MouseEvent evt) { }
public void mouseEntered(MouseEvent evt) { }
public void mouseExited(MouseEvent evt) { }
} // end nested class Display
} // end class Draw
Draw.html
Code:
<html>
<head>
<TITLE>Simple Paint Program</TITLE>
</head>
<body>
<p align=center>
<applet code="Draw.class" height=250 width=300>
</applet>
</p>
</body>
</html>
Any help as to why it's not working properly would be great. Thanks guys. |
