Hello Everyone. I am trying to use a string to set a color.
i have tried
Color is the string which says a color like black or red
g.setColor (Color.color);and
g.setColor (Color."color");lets say the string color was red it should have this effect
g.setColor (Color.red);Thanks for any help.
I think you will have to set up a HashMap to link the Strings to actual Colors, eg
HashMap<String, Color> map = new HashMap<String, Color>();
map.put("Red", Color.RED);
map.put("Green", Color.GREEN);
// etc
...
String colorName = "Green";
g.setColor(map.get(colorName));Or you could use Refection to access the Color constants by name.
I'm sorry I forgot to add this, but I am working in applet. Does this work in applet?
Is this a homework question?
I'm sorry I forgot to add this, but I am working in applet. Does this work in applet?
I can't see any reason why not.
No this is not. Would you like to see my code and where I am going wrong?
Its a simple 2 player pong game. lol.
here is my code anyway.
// The "RetroPong" class.
import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
public class RetroPong extends Applet implements KeyListener, Runnable
{
int p1x = 75, p1y = 130, p2x = 326, p2y = 130, bx = 200, by = 150, p1dy, p2dy, bdx, bdy, p1score = 0, p2score = 0;
double colgen;
int p1win = 0, p2win = 0;
String color;
Thread thread;
HashMap map;
private Image dbImage;
private Graphics dbg;
// Place instance variables here
public void init ()
{
setBackground (Color.black);
map = new HashMap();
map.put("red", Color.red);
map.put("orange", Color.orange);
map.put("yellow", Color.yellow);
map.put("green", Color.green);
map.put("blue", Color.blue);
map.put("white", Color.white);
map.put("gray", Color.gray);
addKeyListener (this);
// Place the body of the initialization method here
} // init method
public void start ()
{
thread = new Thread (this);
thread.start ();
}
public void stop ()
{
thread.stop ();
}
public void run ()
{
Thread.currentThread ().setPriority (Thread.MIN_PRIORITY);
while (true)
{
// Delay for 20 milliseconds
try
{
Thread.sleep (20);
}
catch (InterruptedException e)
{
}
Thread.currentThread ().setPriority (Thread.MAX_PRIORITY);
if (p1y < 0)
{
p1dy = 0;
p1y = 0;
}
else if (p1y + 40 > 300)
{
p1dy = 0;
p1y = 260;
}
if (p2y < 0)
{
p2dy = 0;
p2y = 0;
}
else if (p2y + 40 > 300)
{
p2dy = 0;
p2y = 260;
}
if (bx + 10 == p2x && by + 5 < p2y + 40 && by + 5 > p2y)
{
bdx = -bdx;
colgen = Math.random ();
}
if (bx == p1x + 5 && by + 5 < p1y + 40 && by + 5 > p1y)
{
bdx = -bdx;
colgen = Math.random ();
}
if ((by >= p1y && by <= p1y + 5 && bx + 5 >= p1x && bx + 5 <= p1x + 5) || (by >= p2y && by <= p2y + 5 && bx + 5 >= p2x && bx + 5 <= p2x + 5))
{
bdy = -bdy;
colgen = Math.random ();
}
if ((by <= p1y + 40 && by >= p1y + 35 && bx + 5 >= p1x && bx + 5 <= p1x + 5) || (by <= p2y + 40 && by >= p2y + 35 && bx + 5 >= p2x && bx + 5 <= p2x + 5))
{
bdy = -bdy;
colgen = Math.random ();
}
if (by + 10 > 300)
{
bdy = -bdy;
}
if (by < 0)
{
bdy = -bdy;
}
if (bx < 0)
{
p2score += 1;
bx = 200;
by = 150;
}
if (bx > 400)
{
p1score += 1;
bx = 200;
by = 150;
}
if (p1score == 10)
{
p1win = 1;
bdx = 0;
bdy = 0;
bx = 200;
by = 0;
repaint();
}
else if (p2score == 10)
{
p2win = 1;
bdx = 0;
bdy = 0;
bx = 200;
by = 0;
repaint();
}
if (colgen > 0.8){
color = "red";
}
else if (colgen > 0.7){
color = "orange";
}
else if (colgen > 0.6){
color = "yellow";
}
else if (colgen > 0.5){
color = "green";
}
else if (colgen > 0.4){
color = "blue";
}
else if (colgen > 0.2){
color = "gray";
}
else if (colgen > 0.0){
color = "white";
}
bx += bdx;
by += bdy;
p1y += p1dy;
p2y += p2dy;
repaint ();
}
}
public void paint (Graphics g)
{
g.setColor (Color.white);
g.fillRect (p1x, p1y, 5, 40);
g.fillRect (p2x, p2y, 5, 40);
g.fillOval (bx, by, 10, 10);
g.setColor (map.get(color));
g.drawString ("" + p1score, 5, 150);
g.drawString ("" + p2score, 390, 150);
if (p1win == 1)
{
g.drawString ("Player 1 won", 180, 150);
g.drawString ("press n for a new game", 180, 160);
}
else if (p2win == 1)
{
g.drawString ("Player 2 won", 180, 150);
g.drawString ("press n for a new game", 180, 160);
}
// Place the body of the drawing method here
} // paint method
public void keyPressed (KeyEvent e)
{
int key = e.getKeyCode ();
if (p1win == 0 && p2win == 0)
{
if (key == KeyEvent.VK_UP)
{
p2dy = -3;
repaint ();
}
else if (key == KeyEvent.VK_DOWN)
{
p2dy = 3;
repaint ();
}
if (key == KeyEvent.VK_SHIFT)
{
p1dy = -3;
repaint ();
}
else if (key == KeyEvent.VK_CONTROL)
{
p1dy = 3;
repaint ();
}
if (key == KeyEvent.VK_SPACE && bdx == 0 && bdy == 0)
{
bdx = 2;
bdy = 2;
bx = 200;
by = 150;
}
}
else
{
p1dy = 0;
p2dy = 0;
bdx = 0;
bdy = 0;
}
if (key == KeyEvent.VK_N)
{
p1win = 0;
p2win = 0;
bdx = 2;
bdy = -2;
p1score = 0;
p2score = 0;
repaint();
}
}
public void keyReleased (KeyEvent e)
{
}
public void keyTyped (KeyEvent e)
{
}
public void update (Graphics g)
{
// initialize doublebuffers
if (dbImage == null)
{
dbImage = createImage (this.getSize ().width, this.getSize ().height);
dbg = dbImage.getGraphics ();
}
// save background
dbg.setColor (getBackground ());
dbg.fillRect (0, 0, this.getSize ().width, this.getSize ().height);
// draw foreground on background
dbg.setColor (getForeground ());
paint (dbg);
// Now indicate ready drawn picture Offscreen on the right screen
g.drawImage (dbImage, 0, 0, this);
}
} // RetroPong classIf this isn't homework then it's OK for me to collaborate!
This uses Reflection - it's not optimised or polished, but it shows the idea
public static Color getColorByName(String colorName) {
// get all the fields declared in the Color class...
Field[] fields = Color.class.getDeclaredFields();
for (Field f : fields) {
if (f.getName().equals(colorName.toUpperCase())) {
// found a field with name matching
try {
// return the (Color) value of the field
return (Color) f.get(null);
} catch (Exception e) {
e.printStackTrace(); // should not happen
}
}
}
return null; // no field has a matching name
}Having looked v. quickly at your code I don't see why you are working with Strings for colors in the first place! Instead of
String color:
...
if (colgen > 0.8){
color = "red";
// now we have the problem of converting to an actual Colorwhy not
Color color
...
if (colgen > 0.8){
color = Color.RED;
// now we have the actual Color ready to useThanks that worked.
ps - much shorter version of Color lookup by name...
// get a Color from a String containing a standard color name
public static Color getColorByName(String colorName) {
try {
Field f = Color.class.getField(colorName.toUpperCase());
return (Color) f.get(null);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}Thanks again everyone
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