Exiting an applet with a QUIT button

Hi all,
Please excuse me if this questions has been asked 1001 times before.
I am creating a quit button in a trusted applet, but it seems that the System.exit(0) call is not permitted, with the following message:
"Exception in thread "AWT-EventQueue-1" java.security.AccessControlException: access denied (java.lang.RuntimePermission exitVM)"
Any comments will be much appreciated!

It is a JApplet.
In fact, there is not even a client machine, because
JVM is started on the host itself , an XP OS.Then that machine is the client.
My objective is to be able to close all applet
windows of the JApplet using a button, instead of
having to kill the window manually, which I consider
to be less <graceful>.
Basically, I look for the equivalent of
System.exit(0) using JFrame.You'll have to exit the browser-window which loaded the applet . You cannot close another application through Java.

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I Have an applet cobbled from the net & modified. Is works but needs one major event added. It draws "Graphics.drawline" boxes with a text "String" inside each box ( the text string represents an URL location). These "boxes" are objects which are "draggable to other locations on canvas & therefore can be independently positioned by user. Each box redraws itself periodically to a slightly different screen location & becomes stationary after a 5 or 6 seconds. The point is, all of this "drag & mobility" behavior must remain intact & is not part of the "problem task".
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or
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"g.drawString(doit, x - (w-10)/2, (y - (h-4)/2) + fm.getAscent());"
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" if ("NewUrl".equals(arg)) { "
and ends with with lines:
" return true; "
" } " //< -- end of above if block
This full "if" block can be seen in the listing below:
This "if" block creates the "NewUrl" button. Of course, I got a bunch of errors when I tried to copy this block to the above location:
variable: "arg" "not found in class GraphPanel".
methods: "getcodebase, showstatus, getappletcontext()"
"not found in class GraphPanel".
----------- The applet code in total follows next
Here are both the java & htm complete source.
import java.net.MalformedURLException;
import java.net.URL;
import java.net.*;
import java.util.*;
import java.awt.*;
import java.applet.Applet;
import java.applet.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.event.*;
class Node {
double x;
double y;
double dx;
double dy;
boolean fixed;
String lbl;
class Edge {
int from;
int to;
double len;
} // eEdgeCla
class GraphPanel extends Panel implements Runnable {
Box box;
int nnodes;
Node nodes[] = new Node[100];
int nedges;
Edge edges[] = new Edge[200];
Thread relaxer;
boolean showit;
boolean random;
GraphPanel(Box box) {
this.box = box;
} //ebox
int findNode(String lbl) {
for (int i = 0 ; i < nnodes ; i++) {
if (nodes.lbl.equals(lbl)) {
return i;
return addNode(lbl);
int addNode(String lbl) {
Node n = new Node();
n.x = 10 + 380*Math.random();
n.y = 10 + 380*Math.random();
n.lbl = lbl;
nodes[nnodes] = n;
return nnodes++;
void addEdge(String from, String to, int len) {
Edge e = new Edge();
e.from = findNode(from);
e.to = findNode(to);
e.len = len;
edges[nedges++] = e;
public void run() {
int i3=0;
while (true) {
relax();
if (random && (Math.random() < 0.03)) {
Node n = nodes[(int) (1 * nnodes) ]; // no
if (!n.fixed) {
n.x += (100*0.02) - 50;
n.y += (100*0.02) - 50; //
try {
Thread.sleep(4000);
} catch (InterruptedException e) {
break;
i3++;
} //ew
} // epublrun()
synchronized void relax() {
for (int i = 0 ; i < nedges ; i++) {
Edge e = edges;
double vx = nodes[e.to].x - nodes[e.from].x;
double vy = nodes[e.to].y - nodes[e.from].y;
double len = Math.sqrt(vx * vx + vy * vy);
double f = (edges.len - len) / (len * 3) ;
double dx = f * vx;
double dy = f * vy;
nodes[e.to].dx += dx;
nodes[e.to].dy += dy;
nodes[e.from].dx += -dx;
nodes[e.from].dy += -dy;
} //efo
for (int i = 0 ; i < nnodes ; i++) {
Node n1 = nodes;
double dx = 0;
double dy = 0;
for (int j = 0 ; j < nnodes ; j++) {
if (i == j) {
continue;
Node n2 = nodes[j];
double vx = n1.x - n2.x;
double vy = n1.y - n2.y;
double len = vx * vx + vy * vy;
if (len == 0) {
dx += 0.02;
dy += 0.02;
} else if (len < 100*100) {
dx += vx / len;
dy += vy / len;
} //ef3a
double dlen = dx * dx + dy * dy;
if (dlen > 0) {
dlen = Math.sqrt(dlen) / 2;
n1.dx += dx / dlen;
n1.dy += dy / dlen;
} //ef3
Dimension d = size();
// f4
for (int i = 0 ; i < nnodes ; i++) {
Node n = nodes;
if (!n.fixed) {
n.x += Math.max(-5, Math.min(5, n.dx));
n.y += Math.max(-5, Math.min(5, n.dy));
if (n.x < 0) {
n.x = 0;
} else if (n.x > d.width) {
n.x = d.width;
if (n.y < 0) {
n.y = 0;
} else if (n.y > d.height) {
n.y = d.height;
n.dx /= 2;
n.dy /= 2;
repaint();
Node pick;
boolean pickfixed;
Image offscreen;
Dimension offscreensize;
Graphics offgraphics;
final Color fixedColor = Color.green;
final Color selectColor = Color.gray;
final Color edgeColor = Color.black;
final Color nodeColor = new Color(200, 90, 50);
final Color showitColor = Color.gray;
final Color arcColor1 = Color.black;
final Color arcColor2 = Color.orange;
final Color arcColor3 = Color.blue;
public void paintNode( Graphics g, Node n, FontMetrics fm) {
int x = (int)n.x;
int y = (int)n.y;
g.setColor((n == pick) ? selectColor : (n.fixed ? fixedColor : nodeColor));
int w = fm.stringWidth(n.lbl) + 10;
int h = fm.getHeight() + 4;
g.fillRect(x - w/2, y - h / 2, w, h);
g.setColor(Color.black);
g.drawRect(x - w/2, y - h / 2, w-1, h-1);
String doit = n.lbl.replace('x','/');
g.drawString(doit, x - (w-10)/2, (y - (h-4)/2) + fm.getAscent());
} // epa
public synchronized void update(Graphics g) {
Dimension d = size();
if ((offscreen == null) || (d.width != offscreensize.width) || (d.height != offscreensize.height)) {
offscreen = createImage(d.width, d.height);
offscreensize = d;
offgraphics = offscreen.getGraphics();
offgraphics.setFont(getFont());
offgraphics.setColor(getBackground());
offgraphics.fillRect(0, 0, d.width, d.height);
for (int i = 0 ; i < nedges ; i++) {
Edge e = edges;
int x1 = (int)nodes[e.from].x;
int y1 = (int)nodes[e.from].y;
int x2 = (int)nodes[e.to].x;
int y2 = (int)nodes[e.to].y;
int len = (int)Math.abs(Math.sqrt((x1-x2)*(x1-x2) + (y1-y2)*(y1-y2)) - e.len);
offgraphics.setColor((len < 10) ? arcColor1 : (len < 20 ? arcColor2 : arcColor3)) ;
offgraphics.drawLine(x1, y1, x2, y2);
if (showit) {
String lbl = String.valueOf(len);
offgraphics.setColor(showitColor);
offgraphics.drawString("href= http://localhost:"+lbl, x1 + (x2-x1)/2, y1 + (y2-y1)/2);
offgraphics.setColor(edgeColor);
} //ef5
FontMetrics fm = offgraphics.getFontMetrics();
for (int i = 0 ; i < nnodes ; i++) {
paintNode( offgraphics, nodes, fm); //or
g.drawImage(offscreen, 0, 0, null);
public synchronized boolean mouseDown(Event evt, int x, int y) {
double bestdist = Double.MAX_VALUE;
for (int i = 0 ; i < nnodes ; i++) {
Node n = nodes;
double dist = (n.x - x) * (n.x - x) + (n.y - y) * (n.y - y);
if (dist < bestdist) {
pick = n;
bestdist = dist;
pickfixed = pick.fixed;
pick.fixed = true;
pick.x = x;
pick.y = y;
repaint();
return true;
public synchronized boolean mouseDrag(Event evt, int x, int y) {
pick.x = x;
pick.y = y;
repaint();
return true;
} //e-pubsyncmousedrag
public synchronized boolean mouseUp(Event evt, int x, int y) {
pick.x = x;
pick.y = y;
pick.fixed = pickfixed;
pick = null;
repaint();
return true;
public void start() {
relaxer = new Thread(this);
relaxer.start();
public void stop() {
relaxer.stop();
public class Box extends Applet {
GraphPanel panel;
public void init() {
setLayout(new BorderLayout());
panel = new GraphPanel(this);
add("Center", panel);
Panel p = new Panel();
add("South", p);
p.add(new Button("Reposition"));
p.add(new Button("NewUrl"));
p.add(new Checkbox("Showit"));
String edges = getParameter("edges"); // putinli
for (StringTokenizer t = new StringTokenizer(edges, ",") ; t.hasMoreTokens() ; ) {
String str = t.nextToken();
int i = str.indexOf('-');
if (i > 0) { int len = 50;
int j = str.indexOf('/');
if (j > 0) {
len = Integer.valueOf(str.substring(j+1)).intValue();
str = str.substring(0, j);
panel.addEdge(str.substring(0,i), str.substring(i+1), len);
} //ef8
Dimension d = size();
String center = getParameter("center");
if (center != null){
Node n = panel.nodes[panel.findNode(center)];
n.x = d.width / 2;
n.y = d.height / 2;
n.fixed = true;
} // eif
} // ep
public void start() {
panel.start();
public void stop() {
panel.stop();
public boolean action(Event evt, Object arg) {
if (arg instanceof Boolean) {
if (((Checkbox)evt.target).getLabel().equals("Showit")) {
panel.showit = ((Boolean)arg).booleanValue();
}// e-
else {
panel.random = ((Boolean)arg).booleanValue();
return true;
} // e-if instof bool
if ("Reposition".equals(arg)) {
Dimension d = size();
for (int i = 0 ; i < panel.nnodes ; i++) {
Node n = panel.nodes;
if (!n.fixed) {
n.x = 10 + (d.width-20)*Math.random();
n.y = 10 + (d.height-20)*Math.random();
} //ei
} //ef9
return true;
} //eif scram
if ("NewUrl".equals(arg)) {
Dimension d = size();
URL url = getCodeBase();
try {
getAppletContext().showDocument( new URL(url+"main.htm"), "_blank" );
try {
Thread.sleep(1000);
} catch (InterruptedException e) { }
} catch(MalformedURLException e) {
showStatus("814 URL not found");
for (int i = 0 ; i < panel.nnodes ; i++) {
Node n = panel.nodes;
if (!n.fixed) {
n.x += (80*0.02) - 40;
n.y += (80*0.02) - 40;
return true;
} //ei
return false;
-----------------------htm file to launch------------------------------
<html>
<head>
<title>R
</title>
</head>
<body>
<h3>
<center>
R
</center>
</h3>
I
<b>
</b>
<table border = 1>
<td>De<td>Test List<tr>
<td>N <td><tr>
<td>N <td><tr>
</table>
<b>view </b>
<applet code="Box.class" CODEBASE=. width=1000 height=600
ALT="Test ">
<param name=edges value="http:xxabc.htm-http:xxnet.htm,http:xxthis.htm-http:xx.comet.htm,http:xxnewsighting.htm-http:xxstar.htm,http:xxmoon.htm-http:xxNeptune.htm">
<hr>
</applet>
</b>
<p>
<table border = 1>
<tr>
<tr>
</table>
</html>
</body>
instructions to compile :
0 : The discussion becomes easy to follow after 1st compiling
& viewing the applet.
1. : cut out applet code.
2. : the post somehow deleted all references to "" <--- HERE
see, the data has been deleted again as I preview this post.
( that "" should contain an "i" array increment argument:
"open square bracket" "i" "close square bracket" ) array
so "javac Box.java" will get 10 errors. These "[" "i" "]"
array args must be replaced to compile the code.
3. : All array variables inside the 10 "for" loops ( the bare words
"edges" and "nodes" ) without array increment "i" should
read "edges" "[" "i" "]" & "nodes" "[" "i" "]".
The 10 location lines are approx:
line #65, #129, #136, #149, #195, #283, #311, #331, #477, #522
4. : These 10 edits reqresent a missing "i" to all 10 for loop arrays.
for eddges & nodes. fix this & javac Box.java" will get
4 class files.
5. : cut "Box.htm" from post & do "appletviewer Box.htm"
or put in an apache "htdoc" or tomcat "servlet" http delivered
directory & call "http://localhost/Box.htm.
6. : of course, selecting the event button "NewUrl" will not
work in appletviewer but will work in an http web location.
7. : post your questions to problem or fixes to problem as I'm
monitoring closely. TIA.

Thanks for code post tip to fix array deletion problem.
Here is code reposted using delimiters with will
compile straight out of cut/paste.import java.net.MalformedURLException;
import java.net.URL;
import java.net.*;
import java.util.*;
import java.awt.*;
import java.applet.Applet;
import java.applet.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.event.*;
class Node {
double x;
double y;
double dx;
double dy;
boolean fixed;
String lbl;
class Edge {
int from;
int to;
double len;
} // eEdgeCla
class GraphPanel extends Panel implements Runnable {
Box box;
int nnodes;
Node nodes[] = new Node[100];
int nedges;
Edge edges[] = new Edge[200];
Thread relaxer;
boolean showit;
boolean random;
GraphPanel(Box box) {
this.box = box;
} //ebox
int findNode(String lbl) {
for (int i = 0 ; i < nnodes ; i++) {
//if (nodes.lbl.equals(lbl)) {
if (nodes.lbl.equals(lbl)) {
return i;
return addNode(lbl);
int addNode(String lbl) {
Node n = new Node();
n.x = 10 + 380*Math.random();
n.y = 10 + 380*Math.random();
n.lbl = lbl;
nodes[nnodes] = n;
return nnodes++;
void addEdge(String from, String to, int len) {
Edge e = new Edge();
e.from = findNode(from);
e.to = findNode(to);
e.len = len;
edges[nedges++] = e;
public void run() {
int i3=0;
while (true) {
relax();
if (random && (Math.random() < 0.03)) {
Node n = nodes[(int) (1 * nnodes) ]; // no
if (!n.fixed) {
n.x += (100*0.02) - 50;
n.y += (100*0.02) - 50; //
try {
Thread.sleep(4000);
} catch (InterruptedException e) {
break;
i3++;
} //ew
} // epublrun()
synchronized void relax() {
for (int i = 0 ; i < nedges ; i++) {
//Edge e = edges;
Edge e = edges[i];
double vx = nodes[e.to].x - nodes[e.from].x;
double vy = nodes[e.to].y - nodes[e.from].y;
double len = Math.sqrt(vx * vx + vy * vy);
//double f = (edges.len - len) / (len * 3) ;
double f = (edges[i].len - len) / (len * 3) ;
double dx = f * vx;
double dy = f * vy;
nodes[e.to].dx += dx;
nodes[e.to].dy += dy;
nodes[e.from].dx += -dx;
nodes[e.from].dy += -dy;
} //efo
for (int i = 0 ; i < nnodes ; i++) {
//Node n1 = nodes[i];
Node n1 = nodes[i];
double dx = 0;
double dy = 0;
for (int j = 0 ; j < nnodes ; j++) {
if (i == j) {
continue;
Node n2 = nodes[j];
double vx = n1.x - n2.x;
double vy = n1.y - n2.y;
double len = vx * vx + vy * vy;
if (len == 0) {
dx += 0.02;
dy += 0.02;
} else if (len < 100*100) {
dx += vx / len;
dy += vy / len;
} //ef3a
double dlen = dx * dx + dy * dy;
if (dlen > 0) {
dlen = Math.sqrt(dlen) / 2;
n1.dx += dx / dlen;
n1.dy += dy / dlen;
} //ef3
Dimension d = size();
// f4
for (int i = 0 ; i < nnodes ; i++) {
//Node n = nodes;
Node n = nodes[i];
if (!n.fixed) {
n.x += Math.max(-5, Math.min(5, n.dx));
n.y += Math.max(-5, Math.min(5, n.dy));
if (n.x < 0) {
n.x = 0;
} else if (n.x > d.width) {
n.x = d.width;
if (n.y < 0) {
n.y = 0;
} else if (n.y > d.height) {
n.y = d.height;
n.dx /= 2;
n.dy /= 2;
repaint();
Node pick;
boolean pickfixed;
Image offscreen;
Dimension offscreensize;
Graphics offgraphics;
final Color fixedColor = Color.green;
final Color selectColor = Color.gray;
final Color edgeColor = Color.black;
final Color nodeColor = new Color(200, 90, 50);
final Color showitColor = Color.gray;
final Color arcColor1 = Color.black;
final Color arcColor2 = Color.orange;
final Color arcColor3 = Color.blue;
public void paintNode( Graphics g, Node n, FontMetrics fm) {
int x = (int)n.x;
int y = (int)n.y;
g.setColor((n == pick) ? selectColor : (n.fixed ? fixedColor : nodeColor));
int w = fm.stringWidth(n.lbl) + 10;
int h = fm.getHeight() + 4;
g.fillRect(x - w/2, y - h / 2, w, h);
g.setColor(Color.black);
g.drawRect(x - w/2, y - h / 2, w-1, h-1);
String doit = n.lbl.replace('x','/');
g.drawString(doit, x - (w-10)/2, (y - (h-4)/2) + fm.getAscent());
} // epa
public synchronized void update(Graphics g) {
Dimension d = size();
if ((offscreen == null) || (d.width != offscreensize.width) || (d.height != offscreensize.height)) {
offscreen = createImage(d.width, d.height);
offscreensize = d;
offgraphics = offscreen.getGraphics();
offgraphics.setFont(getFont());
offgraphics.setColor(getBackground());
offgraphics.fillRect(0, 0, d.width, d.height);
for (int i = 0 ; i < nedges ; i++) {
//Edge e = edges;
Edge e = edges[i];
int x1 = (int)nodes[e.from].x;
int y1 = (int)nodes[e.from].y;
int x2 = (int)nodes[e.to].x;
int y2 = (int)nodes[e.to].y;
int len = (int)Math.abs(Math.sqrt((x1-x2)*(x1-x2) + (y1-y2)*(y1-y2)) - e.len);
offgraphics.setColor((len < 10) ? arcColor1 : (len < 20 ? arcColor2 : arcColor3)) ;
offgraphics.drawLine(x1, y1, x2, y2);
if (showit) {
String lbl = String.valueOf(len);
offgraphics.setColor(showitColor);
offgraphics.drawString("href= http://localhost:"+lbl, x1 + (x2-x1)/2, y1 + (y2-y1)/2);
offgraphics.setColor(edgeColor);
} //ef5
FontMetrics fm = offgraphics.getFontMetrics();
for (int i = 0 ; i < nnodes ; i++) {
//paintNode( offgraphics, nodes, fm); //or
paintNode( offgraphics, nodes[i], fm); //or
g.drawImage(offscreen, 0, 0, null);
public synchronized boolean mouseDown(Event evt, int x, int y) {
double bestdist = Double.MAX_VALUE;
for (int i = 0 ; i < nnodes ; i++) {
//Node n = nodes;
Node n = nodes[i];
double dist = (n.x - x) * (n.x - x) + (n.y - y) * (n.y - y);
if (dist < bestdist) {
pick = n;
bestdist = dist;
pickfixed = pick.fixed;
pick.fixed = true;
pick.x = x;
pick.y = y;
repaint();
return true;
public synchronized boolean mouseDrag(Event evt, int x, int y) {
pick.x = x;
pick.y = y;
repaint();
return true;
} //e-pubsyncmousedrag
public synchronized boolean mouseUp(Event evt, int x, int y) {
pick.x = x;
pick.y = y;
pick.fixed = pickfixed;
pick = null;
repaint();
return true;
public void start() {
relaxer = new Thread(this);
relaxer.start();
public void stop() {
relaxer.stop();
public class Box extends Applet {
GraphPanel panel;
public void init() {
setLayout(new BorderLayout());
panel = new GraphPanel(this);
add("Center", panel);
Panel p = new Panel();
add("South", p);
p.add(new Button("Reposition"));
p.add(new Button("NewUrl"));
p.add(new Checkbox("Showit"));
String edges = getParameter("edges"); // putinli
for (StringTokenizer t = new StringTokenizer(edges, ",") ; t.hasMoreTokens() ; ) {
String str = t.nextToken();
int i = str.indexOf('-');
if (i > 0) { int len = 50;
int j = str.indexOf('/');
if (j > 0) {
len = Integer.valueOf(str.substring(j+1)).intValue();
str = str.substring(0, j);
panel.addEdge(str.substring(0,i), str.substring(i+1), len);
} //ef8
Dimension d = size();
String center = getParameter("center");
if (center != null){
Node n = panel.nodes[panel.findNode(center)];
n.x = d.width / 2;
n.y = d.height / 2;
n.fixed = true;
} // eif
} // ep
public void start() {
panel.start();
public void stop() {
panel.stop();
public boolean action(Event evt, Object arg) {
if (arg instanceof Boolean) {
if (((Checkbox)evt.target).getLabel().equals("Showit")) {
panel.showit = ((Boolean)arg).booleanValue();
}// e-
else {
panel.random = ((Boolean)arg).booleanValue();
return true;
} // e-if instof bool
if ("Reposition".equals(arg)) {
Dimension d = size();
for (int i = 0 ; i < panel.nnodes ; i++) {
//Node n = panel.nodes;
Node n = panel.nodes[i];
if (!n.fixed) {
n.x = 10 + (d.width-20)*Math.random();
n.y = 10 + (d.height-20)*Math.random();
} //ei
} //ef9
return true;
} //eif scram
if ("NewUrl".equals(arg)) {
Dimension d = size();
URL url = getCodeBase();
try {
getAppletContext().showDocument( new URL(url+"main.htm"), "_blank" );
try {
Thread.sleep(1000);
} catch (InterruptedException e) { }
} catch(MalformedURLException e) {
showStatus("814 URL not found");
for (int i = 0 ; i < panel.nnodes ; i++) {
//Node n = panel.nodes;
Node n = panel.nodes[i];
if (!n.fixed) {
n.x += (80*0.02) - 40;
n.y += (80*0.02) - 40;
return true;
} //ei
return false;

Floating "boxes" applet with drag events need ckick events

I Have an applet cobbled from the net & modified. Is works but needs one major event added. It draws "Graphics.drawline" boxes with a text "String" inside each box ( the text string represents an URL location). These "boxes" are objects which are "draggable to other locations on canvas & therefore can be independently positioned by user. Each box redraws itself periodically to a slightly different screen location & becomes stationary after a 5 or 6 seconds. The point is, all of this "drag & mobility" behavior must remain intact & is not part of the "problem task".
Task: Need to have an "event" behavior added in one of two ways ( or a 3rd way if there is another ) whichever is quickest/ easiest. "Clickable mouse events" must be added to each box. ( boxes are built in a loop so adding to one will add to other locations & create as many "buttons" as there are boxes) . At each box's location, clicking one box should be an event which fires & clicking a different box should be a separate event which fires. Separate , so that URL location can be "hotlinked" to each box. That URL is currently displayed in the boxes (visible when running applet).
1st possible solution: Exchange these "boxes" which appear on canvas into clickable event "Graph panel.buttons" ( for example or some other clickable object) which maintains existing "drag" behavior of boxes. These buttons must each have "clickability" with mouse events to enable placing "getAppletContext. showDocument()" code with these events ( e.g., "hotlinked" to http locations).
or
2nd possible solution:. The drawstring boxes are currently dead string text with no event model other than the "drag" feature associated with each box. Must add an additional mouse event behavior to existing boxes so they are "clickable" ( or text inside is clickable) and can then execute "showDocument()" URL when clicked independently.
Maybe there is a #3. I don't know what that would be. Open to try anything without losing the drag & placement mobility of existing boxes.
These "boxes" could be images, or event buttons - doesnt matter.
Not sure if #2 is possible & have not been able to accomplish #1. Must stay within existing AWT framework so IE browsers can run it natively ( which of course IE cannot run Swing graphics unless a Sun plugin loaded ).
Applet is a single file ( creating 4 classes).
html file (which invokes it) passes a string param which is broken into above noted URL strings in each box.
Running this applet, you see a "button" event ( at base of canvas labeled "NewUrl" ) which pops up an url location when clicked ( using "showdocument"). This button is not attached to locations or text of each box object ( which is the "task" to accomplish) . The button does represent the kind of event behavior which each "box" should have when task is achieved. So the box can be exchanged with buttons or the boxes can be imbued with events to hyperlink like a button.
In spirit of solution #1, here is the bonehead attempt I tried which did not work: copied entire "if" block of logic from the button event (sited in preceding paragraph) into region of code which builds boxes ( "for" loop of "drawstring" method).
"g.drawString(doit, x - (w-10)/2, (y - (h-4)/2) + fm.getAscent());"
I copied all the "if" block of logic for button creation into the area immediately after the above line ( for loop which builds the boxes). Hoping that I could create buttons with events, along with all the boxes (which are getting created using "drawstring" above in a "for" loop). These "buttons" must also have positioning info of each box to appear in different locations on the canvas. Positioning data is not in that "if" block of code but it would have been a start to get the multiple buttons created ( even if all drawn in one spot). The "if" code block I've provieded for an example begins with the line:
" if ("NewUrl".equals(arg)) { "
and ends with with lines:
" return true; "
" } " //< -- end of above if block
This full "if" block can be seen in the listing below:
This "if" block creates the "NewUrl" button. Of course, I got a bunch of errors when I tried to copy this block to the above location:
variable: "arg" "not found in class GraphPanel".
methods: "getcodebase, showstatus, getappletcontext()"
"not found in class GraphPanel".
----------- The applet code in total follows next
Here are both the java & htm complete source.
import java.net.MalformedURLException;
import java.net.URL;
import java.net.*;
import java.util.*;
import java.awt.*;
import java.applet.Applet;
import java.applet.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.event.*;
class Node {
double x;
double y;
double dx;
double dy;
boolean fixed;
String lbl;
class Edge {
int from;
int to;
double len;
} // eEdgeCla
class GraphPanel extends Panel implements Runnable {
Box box;
int nnodes;
Node nodes[] = new Node[100];
int nedges;
Edge edges[] = new Edge[200];
Thread relaxer;
boolean showit;
boolean random;
GraphPanel(Box box) {
this.box = box;
} //ebox
int findNode(String lbl) {
for (int i = 0 ; i < nnodes ; i++) {
if (nodes.lbl.equals(lbl)) {
return i;
return addNode(lbl);
int addNode(String lbl) {
Node n = new Node();
n.x = 10 + 380*Math.random();
n.y = 10 + 380*Math.random();
n.lbl = lbl;
nodes[nnodes] = n;
return nnodes++;
void addEdge(String from, String to, int len) {
Edge e = new Edge();
e.from = findNode(from);
e.to = findNode(to);
e.len = len;
edges[nedges++] = e;
public void run() {
int i3=0;
while (true) {
relax();
if (random && (Math.random() < 0.03)) {
Node n = nodes[(int) (1 * nnodes) ]; // no
if (!n.fixed) {
n.x += (100*0.02) - 50;
n.y += (100*0.02) - 50; //
try {
Thread.sleep(4000);
} catch (InterruptedException e) {
break;
i3++;
} //ew
} // epublrun()
synchronized void relax() {
for (int i = 0 ; i < nedges ; i++) {
Edge e = edges;
double vx = nodes[e.to].x - nodes[e.from].x;
double vy = nodes[e.to].y - nodes[e.from].y;
double len = Math.sqrt(vx * vx + vy * vy);
double f = (edges.len - len) / (len * 3) ;
double dx = f * vx;
double dy = f * vy;
nodes[e.to].dx += dx;
nodes[e.to].dy += dy;
nodes[e.from].dx += -dx;
nodes[e.from].dy += -dy;
} //efo
for (int i = 0 ; i < nnodes ; i++) {
Node n1 = nodes;
double dx = 0;
double dy = 0;
for (int j = 0 ; j < nnodes ; j++) {
if (i == j) {
continue;
Node n2 = nodes[j];
double vx = n1.x - n2.x;
double vy = n1.y - n2.y;
double len = vx * vx + vy * vy;
if (len == 0) {
dx += 0.02;
dy += 0.02;
} else if (len < 100*100) {
dx += vx / len;
dy += vy / len;
} //ef3a
double dlen = dx * dx + dy * dy;
if (dlen > 0) {
dlen = Math.sqrt(dlen) / 2;
n1.dx += dx / dlen;
n1.dy += dy / dlen;
} //ef3
Dimension d = size();
// f4
for (int i = 0 ; i < nnodes ; i++) {
Node n = nodes;
if (!n.fixed) {
n.x += Math.max(-5, Math.min(5, n.dx));
n.y += Math.max(-5, Math.min(5, n.dy));
if (n.x < 0) {
n.x = 0;
} else if (n.x > d.width) {
n.x = d.width;
if (n.y < 0) {
n.y = 0;
} else if (n.y > d.height) {
n.y = d.height;
n.dx /= 2;
n.dy /= 2;
repaint();
Node pick;
boolean pickfixed;
Image offscreen;
Dimension offscreensize;
Graphics offgraphics;
final Color fixedColor = Color.green;
final Color selectColor = Color.gray;
final Color edgeColor = Color.black;
final Color nodeColor = new Color(200, 90, 50);
final Color showitColor = Color.gray;
final Color arcColor1 = Color.black;
final Color arcColor2 = Color.orange;
final Color arcColor3 = Color.blue;
public void paintNode( Graphics g, Node n, FontMetrics fm) {
int x = (int)n.x;
int y = (int)n.y;
g.setColor((n == pick) ? selectColor : (n.fixed ? fixedColor : nodeColor));
int w = fm.stringWidth(n.lbl) + 10;
int h = fm.getHeight() + 4;
g.fillRect(x - w/2, y - h / 2, w, h);
g.setColor(Color.black);
g.drawRect(x - w/2, y - h / 2, w-1, h-1);
String doit = n.lbl.replace('x','/');
g.drawString(doit, x - (w-10)/2, (y - (h-4)/2) + fm.getAscent());
} // epa
public synchronized void update(Graphics g) {
Dimension d = size();
if ((offscreen == null) || (d.width != offscreensize.width) || (d.height != offscreensize.height)) {
offscreen = createImage(d.width, d.height);
offscreensize = d;
offgraphics = offscreen.getGraphics();
offgraphics.setFont(getFont());
offgraphics.setColor(getBackground());
offgraphics.fillRect(0, 0, d.width, d.height);
for (int i = 0 ; i < nedges ; i++) {
Edge e = edges;
int x1 = (int)nodes[e.from].x;
int y1 = (int)nodes[e.from].y;
int x2 = (int)nodes[e.to].x;
int y2 = (int)nodes[e.to].y;
int len = (int)Math.abs(Math.sqrt((x1-x2)*(x1-x2) + (y1-y2)*(y1-y2)) - e.len);
offgraphics.setColor((len < 10) ? arcColor1 : (len < 20 ? arcColor2 : arcColor3)) ;
offgraphics.drawLine(x1, y1, x2, y2);
if (showit) {
String lbl = String.valueOf(len);
offgraphics.setColor(showitColor);
offgraphics.drawString("href= http://localhost:"+lbl, x1 + (x2-x1)/2, y1 + (y2-y1)/2);
offgraphics.setColor(edgeColor);
} //ef5
FontMetrics fm = offgraphics.getFontMetrics();
for (int i = 0 ; i < nnodes ; i++) {
paintNode( offgraphics, nodes, fm); //or
g.drawImage(offscreen, 0, 0, null);
public synchronized boolean mouseDown(Event evt, int x, int y) {
double bestdist = Double.MAX_VALUE;
for (int i = 0 ; i < nnodes ; i++) {
Node n = nodes;
double dist = (n.x - x) * (n.x - x) + (n.y - y) * (n.y - y);
if (dist < bestdist) {
pick = n;
bestdist = dist;
pickfixed = pick.fixed;
pick.fixed = true;
pick.x = x;
pick.y = y;
repaint();
return true;
public synchronized boolean mouseDrag(Event evt, int x, int y) {
pick.x = x;
pick.y = y;
repaint();
return true;
} //e-pubsyncmousedrag
public synchronized boolean mouseUp(Event evt, int x, int y) {
pick.x = x;
pick.y = y;
pick.fixed = pickfixed;
pick = null;
repaint();
return true;
public void start() {
relaxer = new Thread(this);
relaxer.start();
public void stop() {
relaxer.stop();
public class Box extends Applet {
GraphPanel panel;
public void init() {
setLayout(new BorderLayout());
panel = new GraphPanel(this);
add("Center", panel);
Panel p = new Panel();
add("South", p);
p.add(new Button("Reposition"));
p.add(new Button("NewUrl"));
p.add(new Checkbox("Showit"));
String edges = getParameter("edges"); // putinli
for (StringTokenizer t = new StringTokenizer(edges, ",") ; t.hasMoreTokens() ; ) {
String str = t.nextToken();
int i = str.indexOf('-');
if (i > 0) { int len = 50;
int j = str.indexOf('/');
if (j > 0) {
len = Integer.valueOf(str.substring(j+1)).intValue();
str = str.substring(0, j);
panel.addEdge(str.substring(0,i), str.substring(i+1), len);
} //ef8
Dimension d = size();
String center = getParameter("center");
if (center != null){
Node n = panel.nodes[panel.findNode(center)];
n.x = d.width / 2;
n.y = d.height / 2;
n.fixed = true;
} // eif
} // ep
public void start() {
panel.start();
public void stop() {
panel.stop();
public boolean action(Event evt, Object arg) {
if (arg instanceof Boolean) {
if (((Checkbox)evt.target).getLabel().equals("Showit")) {
panel.showit = ((Boolean)arg).booleanValue();
}// e-
else {
panel.random = ((Boolean)arg).booleanValue();
return true;
} // e-if instof bool
if ("Reposition".equals(arg)) {
Dimension d = size();
for (int i = 0 ; i < panel.nnodes ; i++) {
Node n = panel.nodes;
if (!n.fixed) {
n.x = 10 + (d.width-20)*Math.random();
n.y = 10 + (d.height-20)*Math.random();
} //ei
} //ef9
return true;
} //eif scram
if ("NewUrl".equals(arg)) {
Dimension d = size();
URL url = getCodeBase();
try {
getAppletContext().showDocument( new URL(url+"main.htm"), "_blank" );
try {
Thread.sleep(1000);
} catch (InterruptedException e) { }
} catch(MalformedURLException e) {
showStatus("814 URL not found");
for (int i = 0 ; i < panel.nnodes ; i++) {
Node n = panel.nodes;
if (!n.fixed) {
n.x += (80*0.02) - 40;
n.y += (80*0.02) - 40;
return true;
} //ei
return false;
-----------------------htm file to launch------------------------------
<html>
<head>
<title>R
</title>
</head>
<body>
<h3>
<center>
R
</center>
</h3>
I
<b>
</b>
<table border = 1>
<td>De<td>Test List<tr>
<td>N <td><tr>
<td>N <td><tr>
</table>
<b>view </b>
<applet code="Box.class" CODEBASE=. width=1000 height=600
ALT="Test ">
<param name=edges value="http:xxabc.htm-http:xxnet.htm,http:xxthis.htm-http:xx.comet.htm,http:xxnewsighting.htm-http:xxstar.htm,http:xxmoon.htm-http:xxNeptune.htm">
<hr>
</applet>
</b>
<p>
<table border = 1>
<tr>
<tr>
</table>
</html>
</body>
instructions to compile :
0 : The discussion becomes easy to follow after 1st compiling
& viewing the applet.
1. : cut out applet code.
2. : the post somehow deleted all references to "" <--- HERE
see, the data has been deleted again as I preview this post.
( that "" should contain an "i" array increment argument:
"open square bracket" "i" "close square bracket" ) array
so "javac Box.java" will get 10 errors. These "[" "i" "]"
array args must be replaced to compile the code.
3. : All array variables inside the 10 "for" loops ( the bare words
"edges" and "nodes" ) without array increment "i" should
read "edges" "[" "i" "]" & "nodes" "[" "i" "]".
The 10 location lines are approx:
line #65, #129, #136, #149, #195, #283, #311, #331, #477, #522
4. : These 10 edits reqresent a missing "i" to all 10 for loop arrays.
for eddges & nodes. fix this & javac Box.java" will get
4 class files.
5. : cut "Box.htm" from post & do "appletviewer Box.htm"
or put in an apache "htdoc" or tomcat "servlet" http delivered
directory & call "http://localhost/Box.htm.
6. : of course, selecting the event button "NewUrl" will not
work in appletviewer but will work in an http web location.
7. : post your questions to problem or fixes to problem as I'm
monitoring closely. TIA.

Thanks for code post tip to fix array index deletion problem.
Here is code reposted using "code" delimiters which will
compile straight out of cut/paste.
import java.net.MalformedURLException;
import java.net.URL;
import java.net.*;
import java.util.*;
import java.awt.*;
import java.applet.Applet;
import java.applet.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.event.*;
class Node {
double x;
double y;
double dx;
double dy;
boolean fixed;
String lbl;
class Edge {
int from;
int to;
double len;
} // eEdgeCla
class GraphPanel extends Panel implements Runnable {
Box box;
int nnodes;
Node nodes[] = new Node[100];
int nedges;
Edge edges[] = new Edge[200];
Thread relaxer;
boolean showit;
boolean random;
GraphPanel(Box box) {
this.box = box;
} //ebox
int findNode(String lbl) {
for (int i = 0 ; i < nnodes ; i++) {
//if (nodes.lbl.equals(lbl)) {
if (nodes.lbl.equals(lbl)) {
return i;
return addNode(lbl);
int addNode(String lbl) {
Node n = new Node();
n.x = 10 + 380*Math.random();
n.y = 10 + 380*Math.random();
n.lbl = lbl;
nodes[nnodes] = n;
return nnodes++;
void addEdge(String from, String to, int len) {
Edge e = new Edge();
e.from = findNode(from);
e.to = findNode(to);
e.len = len;
edges[nedges++] = e;
public void run() {
int i3=0;
while (true) {
relax();
if (random && (Math.random() < 0.03)) {
Node n = nodes[(int) (1 * nnodes) ]; // no
if (!n.fixed) {
n.x += (100*0.02) - 50;
n.y += (100*0.02) - 50; //
try {
Thread.sleep(4000);
} catch (InterruptedException e) {
break;
i3++;
} //ew
} // epublrun()
synchronized void relax() {
for (int i = 0 ; i < nedges ; i++) {
//Edge e = edges;
Edge e = edges[i];
double vx = nodes[e.to].x - nodes[e.from].x;
double vy = nodes[e.to].y - nodes[e.from].y;
double len = Math.sqrt(vx * vx + vy * vy);
//double f = (edges.len - len) / (len * 3) ;
double f = (edges[i].len - len) / (len * 3) ;
double dx = f * vx;
double dy = f * vy;
nodes[e.to].dx += dx;
nodes[e.to].dy += dy;
nodes[e.from].dx += -dx;
nodes[e.from].dy += -dy;
} //efo
for (int i = 0 ; i < nnodes ; i++) {
//Node n1 = nodes[i];
Node n1 = nodes[i];
double dx = 0;
double dy = 0;
for (int j = 0 ; j < nnodes ; j++) {
if (i == j) {
continue;
Node n2 = nodes[j];
double vx = n1.x - n2.x;
double vy = n1.y - n2.y;
double len = vx * vx + vy * vy;
if (len == 0) {
dx += 0.02;
dy += 0.02;
} else if (len < 100*100) {
dx += vx / len;
dy += vy / len;
} //ef3a
double dlen = dx * dx + dy * dy;
if (dlen > 0) {
dlen = Math.sqrt(dlen) / 2;
n1.dx += dx / dlen;
n1.dy += dy / dlen;
} //ef3
Dimension d = size();
// f4
for (int i = 0 ; i < nnodes ; i++) {
//Node n = nodes;
Node n = nodes[i];
if (!n.fixed) {
n.x += Math.max(-5, Math.min(5, n.dx));
n.y += Math.max(-5, Math.min(5, n.dy));
if (n.x < 0) {
n.x = 0;
} else if (n.x > d.width) {
n.x = d.width;
if (n.y < 0) {
n.y = 0;
} else if (n.y > d.height) {
n.y = d.height;
n.dx /= 2;
n.dy /= 2;
repaint();
Node pick;
boolean pickfixed;
Image offscreen;
Dimension offscreensize;
Graphics offgraphics;
final Color fixedColor = Color.green;
final Color selectColor = Color.gray;
final Color edgeColor = Color.black;
final Color nodeColor = new Color(200, 90, 50);
final Color showitColor = Color.gray;
final Color arcColor1 = Color.black;
final Color arcColor2 = Color.orange;
final Color arcColor3 = Color.blue;
public void paintNode( Graphics g, Node n, FontMetrics fm) {
int x = (int)n.x;
int y = (int)n.y;
g.setColor((n == pick) ? selectColor : (n.fixed ? fixedColor : nodeColor));
int w = fm.stringWidth(n.lbl) + 10;
int h = fm.getHeight() + 4;
g.fillRect(x - w/2, y - h / 2, w, h);
g.setColor(Color.black);
g.drawRect(x - w/2, y - h / 2, w-1, h-1);
String doit = n.lbl.replace('x','/');
g.drawString(doit, x - (w-10)/2, (y - (h-4)/2) + fm.getAscent());
} // epa
public synchronized void update(Graphics g) {
Dimension d = size();
if ((offscreen == null) || (d.width != offscreensize.width) || (d.height != offscreensize.height)) {
offscreen = createImage(d.width, d.height);
offscreensize = d;
offgraphics = offscreen.getGraphics();
offgraphics.setFont(getFont());
offgraphics.setColor(getBackground());
offgraphics.fillRect(0, 0, d.width, d.height);
for (int i = 0 ; i < nedges ; i++) {
//Edge e = edges;
Edge e = edges[i];
int x1 = (int)nodes[e.from].x;
int y1 = (int)nodes[e.from].y;
int x2 = (int)nodes[e.to].x;
int y2 = (int)nodes[e.to].y;
int len = (int)Math.abs(Math.sqrt((x1-x2)*(x1-x2) + (y1-y2)*(y1-y2)) - e.len);
offgraphics.setColor((len < 10) ? arcColor1 : (len < 20 ? arcColor2 : arcColor3)) ;
offgraphics.drawLine(x1, y1, x2, y2);
if (showit) {
String lbl = String.valueOf(len);
offgraphics.setColor(showitColor);
offgraphics.drawString("href= http://localhost:"+lbl, x1 + (x2-x1)/2, y1 + (y2-y1)/2);
offgraphics.setColor(edgeColor);
} //ef5
FontMetrics fm = offgraphics.getFontMetrics();
for (int i = 0 ; i < nnodes ; i++) {
//paintNode( offgraphics, nodes, fm); //or
paintNode( offgraphics, nodes[i], fm); //or
g.drawImage(offscreen, 0, 0, null);
public synchronized boolean mouseDown(Event evt, int x, int y) {
double bestdist = Double.MAX_VALUE;
for (int i = 0 ; i < nnodes ; i++) {
//Node n = nodes;
Node n = nodes[i];
double dist = (n.x - x) * (n.x - x) + (n.y - y) * (n.y - y);
if (dist < bestdist) {
pick = n;
bestdist = dist;
pickfixed = pick.fixed;
pick.fixed = true;
pick.x = x;
pick.y = y;
repaint();
return true;
public synchronized boolean mouseDrag(Event evt, int x, int y) {
pick.x = x;
pick.y = y;
repaint();
return true;
} //e-pubsyncmousedrag
public synchronized boolean mouseUp(Event evt, int x, int y) {
pick.x = x;
pick.y = y;
pick.fixed = pickfixed;
pick = null;
repaint();
return true;
public void start() {
relaxer = new Thread(this);
relaxer.start();
public void stop() {
relaxer.stop();
public class Box extends Applet {
GraphPanel panel;
public void init() {
setLayout(new BorderLayout());
panel = new GraphPanel(this);
add("Center", panel);
Panel p = new Panel();
add("South", p);
p.add(new Button("Reposition"));
p.add(new Button("NewUrl"));
p.add(new Checkbox("Showit"));
String edges = getParameter("edges"); // putinli
for (StringTokenizer t = new StringTokenizer(edges, ",") ; t.hasMoreTokens() ; ) {
String str = t.nextToken();
int i = str.indexOf('-');
if (i > 0) { int len = 50;
int j = str.indexOf('/');
if (j > 0) {
len = Integer.valueOf(str.substring(j+1)).intValue();
str = str.substring(0, j);
panel.addEdge(str.substring(0,i), str.substring(i+1), len);
} //ef8
Dimension d = size();
String center = getParameter("center");
if (center != null){
Node n = panel.nodes[panel.findNode(center)];
n.x = d.width / 2;
n.y = d.height / 2;
n.fixed = true;
} // eif
} // ep
public void start() {
panel.start();
public void stop() {
panel.stop();
public boolean action(Event evt, Object arg) {
if (arg instanceof Boolean) {
if (((Checkbox)evt.target).getLabel().equals("Showit")) {
panel.showit = ((Boolean)arg).booleanValue();
}// e-
else {
panel.random = ((Boolean)arg).booleanValue();
return true;
} // e-if instof bool
if ("Reposition".equals(arg)) {
Dimension d = size();
for (int i = 0 ; i < panel.nnodes ; i++) {
//Node n = panel.nodes;
Node n = panel.nodes[i];
if (!n.fixed) {
n.x = 10 + (d.width-20)*Math.random();
n.y = 10 + (d.height-20)*Math.random();
} //ei
} //ef9
return true;
} //eif scram
if ("NewUrl".equals(arg)) {
Dimension d = size();
URL url = getCodeBase();
try {
getAppletContext().showDocument( new URL(url+"main.htm"), "_blank" );
try {
Thread.sleep(1000);
} catch (InterruptedException e) { }
} catch(MalformedURLException e) {
showStatus("814 URL not found");
for (int i = 0 ; i < panel.nnodes ; i++) {
//Node n = panel.nodes;
Node n = panel.nodes[i];
if (!n.fixed) {
n.x += (80*0.02) - 40;
n.y += (80*0.02) - 40;
return true;
} //ei
return false;

Right way to exit an applet

Hi,
I am making an applet by extending JApplet. Can anyone please tell what's the right way to stop the applet ie. to complete its execution.
Shoud System.exit() be used, i tried stop and destroy , nothing happened. I have provided a menu inside my applet i want it to exit or complete execution with its window removed when some clicks on exit menu.
Any suggestion is welcome.
thanks
inder

Don't use System.exit in applet, won't work, and would probably throw a security exception.
Only "destroy" your applet by overriding the destroy() method (where you do some clean up, close open connections, release references that takes a lot of memory, etc, nothing else). This method is called by the browser, at least when you close it.
The stop() method should not try to destroy your applet. I think if the browser calls stop(), it will also call start() to start the applet again, but without calling the init() method. The init() method is called if the browser needs to run your applet first time, or again after destroy() has been called as far as I know.
You can get more info if you read the javadoc comments for those methods.

Is there a way to stop all loops( While and For )at once or close the big application with just a button?

How to sop all loops in the application (While, For and subvis ) with a single button? Use the event sturucture?

Yes, if you just need to kill the running application, you can use an event structure in a parallel loop. (See attached code image). Pressing the stop button stops everything! :-)
(Alternatively, you could even call "quit labview".)
LabVIEW Champion . Do more with less code and in less time .
Attachments:
Killall.png ‏6 KB

Can't open a new tab with the + for tabs. Can open with Mid mouse button. Nightly.

When I click The + to open a new tab in Nightly, it does nothing. I can open new tabs with mid ouse button, or right click>open in new tab. Just cant open a new tab via the + button. Started 3 updates ago in nightly (3 days ago pretty much).

Are you using a 32 bit Nightly build or a 64 bit Nightly build?
The 64 bit Nightly build for Windows is only generated to test for compilation errors and doesn't undergo all the tests that other builds get, so the risk that something goes wrong can be quite high.<br />
So if you do use the 64 bit version then try the 32 bit version to see if you still have this problem.
Start Firefox in <u>[[Safe Mode|Safe Mode]]</u> to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).
*Do NOT click the Reset button on the Safe Mode start window.
*https://support.mozilla.org/kb/Safe+Mode
*https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes
Create a new profile as a test to check if your current profile is causing the problems.
See "Creating a profile":
*https://support.mozilla.org/kb/profile-manager-create-and-remove-firefox-profiles
*http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues
If the new profile works then you can transfer some files from an existing profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over the problem.
*http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

Trouble hiding and showing captions with a single button

I am trying to show a caption (MSO) with the click of a button and then hide it again with the same button. I have created a MSO with two states one with the text, one without and then created an icon with a plus sign [normal] that triggers the second state that has the text. After the button is pressed it changes to a minus sign [click] the next step is where I am running into trouble. I just want the user to be able to click the minus button to hide the caption before moving on to the next page or article. I have tried every button state combination but can't hide the caption short of creating a new button somewhere else on the page, this is not desired. I have seen this function in publications like National Geographic, and Vogue so I know it is possible. It seems so simple but I can't figure it out. Being able to close the caption after showing it will add another level of interaction and professionalism to my publication...please help someone.

Being inmersed in this thing, I am gathering some instructions and notes about very basic DPS things for our working team use and my Spanish speakers readers. Here you have the first one: Cómo hacer que un pie de foto se muestre al pulsar encima de la imagen en InDesign para DPS
They are based in Bob Bringhusrt's DPS tips —thanks a lot!—, what I have read in this forum and the Adobe's help data.
There's a translate button that works quite fine.
Is that of any help? Hope so
Gustavo (Posting from heat-melting Madrid)

What's the deal with the home button?

What is with the home button acting all janky all the time. Sometimes it acts as tho it was never pushed and then sometimes it acts at tho it was pushed twice.

i found this on another question and it works perfectly now...........
open a stock iOS app (Weather, Stocks, Clock, etc.). Once the app is open, press your iPhone’s power button until the ‘slide to power off’ screen appears. From that screen, press and hold your Home button until iOS force quits the stock app you have open.
This will recalibrate your home button.

Problem with the back button in the Alv ouput

i have refresh button in output of my alv report when i click on this it is getting refreshed ,now the problem is with the back button after refresh whn i click on back button it is not going to selection screen , i have to click the back button thrice to come out to the selection screen ,if have refreshed the ouput screen twice .
if i dont refresh the back button is working fine , So i have used "call to selection screen 1000" it coming to selection screen without any problem but in selection screen on clicking on back button it is again going back to output screen ,So please suggest what has to be done here .

Hi Brahmananda,
Please try to understand the flow of program and the screen navigation
the click of BACK button triggers PAI and (to the best of my knowledge) you might have called the ALV screen number without any checks ( may be) so it is again taking to the ALV.
try using
in PAI
module exit at exit-command
in program
module exit
case ok_code
when 'BACK'.
LEAVE PROGRAM ( or any thing that you want it to be )
endcase
endmodule
regards
Ramchander rao.K

Exit from Director with error code

Hi all!
How can I exit from director with specifyed error code by
using lingo or JavaScript syntax?
I want to catch its error code in batch file for example to
do something special.
Sample batch file I want to use:
myprojector.exe
if %ERRORLEVEL% == 10 goto GO_TO_SOMETHING_WRONG
But now, by default director quit with error code 0.
Thanks in advance

lis0x90 wrote:
> How can I exit from director with specifyed error code
by using lingo
> or JavaScript syntax?
>
> I want to catch its error code in batch file for example
to do
> something special.
> Sample batch file I want to use:
>
> myprojector.exe
> if %ERRORLEVEL% == 10 goto GO_TO_SOMETHING_WRONG
>
> But now, by default director quit with error code 0.
I don't know of any way to do that, but you could get the
projector to
create a (zero byte) file if there's an error and in the
batch file check
for the existence of that file. (Not forgetting to delete
that file, if it
exists, when the projector starts.)
Andrew

Exiting an applet with a QUIT button

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