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Java - Wait for component to be shown

UPDATE #3: After madProgrammer's suggestions, maybe the timed solution is the best. But no answer has been given to this strange behaviour.
I understand the fact that components are not shown immediately and need to be set.
The problem here is the onShow method, which executes correctly if called from onCreate, but doesn't work if called from the callback method "componentShown".
UPDATE #2: Added a componentListener on fragmentContentPane, to see when actually this component is shown and VALID
fragmentContentPane.addComponentListener(new ComponentAdapter(){
public void componentShown(ComponentEvent e){
if (e.getComponent().isValid()) System.out.println("SHOWN AND VALID!");
}
});
UPDATE:
The show method now gets called in EDT.
public void show() throws InvocationTargetException, InterruptedException{
SwingUtilities.invokeAndWait(new Runnable(){
public void run(){
System.out.println("Showing..");
frame.setVisible(true);
}
});
}
By now, the problem still exists.
Original Post:
I have this code:
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.awt.event.HierarchyEvent;
import java.awt.event.HierarchyListener;
import java.lang.reflect.InvocationTargetException;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.SwingUtilities;
public class TEST {
private JFrame frame;
private JScrollPane contentPane;
private JPanel contentViewport;
private JScrollPane fragmentContentPane;
private JPanel fragmentContentViewport;
public TEST() throws InvocationTargetException, InterruptedException{
SwingUtilities.invokeAndWait(new Runnable(){
public void run(){
onCreate();
}
});
}
public void onCreate(){
System.out.println("On create!");
frame=new JFrame();
contentPane=new JScrollPane();
contentViewport=new JPanel();
contentPane.setViewportView(contentViewport);
frame.setContentPane(contentPane);
frame.addComponentListener(new ComponentAdapter(){
public void componentShown(ComponentEvent e){
onShow();
}
});
}
public void onShow(){
System.out.println("On show!");
fragmentContentViewport=new JPanel();
fragmentContentPane=new JScrollPane(fragmentContentViewport);
fragmentContentPane.addHierarchyListener(new HierarchyListener() {
public void hierarchyChanged(HierarchyEvent e) {
if (e.getChangeFlags()==HierarchyEvent.SHOWING_CHANGED && fragmentContentPane.isShowing()) {
System.out.println("Component is completely shown");
}
}
});
contentViewport.add(fragmentContentPane);
}
public void show(){
frame.setVisible(true);
}
public static final void main(String[] args) throws InvocationTargetException, InterruptedException{
TEST t=new TEST();
t.show();
}
}
The task is simple. I want to get known when the fragmentContentPane has been correctly added and is completely shown.
With this code this never happens, why?
Everything works if the onShow method is called in the ThreadEvent together with onCreate, for example:
public TEST() throws InvocationTargetException, InterruptedException{
SwingUtilities.invokeAndWait(new Runnable(){
public void run(){
onCreate();
onShow();
}
});
}
any help is appreciated

Function to navigate to a web page in Java

I am trying to make a function that allows you to navigate to a webpage. I can how to run the function, I just don't know how to write the part of the program that accesses the webpage. Here is the code that I am using to access the function via a JButton. I would like the program to work on multiple platforms. All of the solutions I have found to this, I either don't understand well enough to modify to my needs, or it isn't multi-platform.
public static void main(String[] args) {
JFrame frame = new JFrame();
JPanel panel = new JPanel();
JButton google = new JButton("Google");
linux.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
openURL("http://www.google.com/");
}
} );
JButton stackoverflow = new JButton("Stackoverflow");
JButton blah = new JButton("blah");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
panel.add(linux);
panel.add(osx);
panel.add(windows);
frame.getContentPane().add(panel);
frame.pack();
frame.setVisible(true);
}
Yes I am aware the last two buttons do nothing.
Here is what I have tried so far:
public static void openURL(String url) {
String osName = System.getProperty("os.name");
try {
if (osName.startsWith("Windows"))
Runtime.getRuntime().exec("rundll32 url.dll,FileProtocolHandler " + url);
else {
String[] browsers = {"firefox", "opera", "konqueror", "epiphany", "mozilla", "netscape", "chrome" };
String browser = null;
for (int count = 0; count < browsers.length && browser == null; count++)
if (Runtime.getRuntime().exec(new String[] {"which", browsers[count]}).waitFor() == 0)
browser = browsers[count];
Runtime.getRuntime().exec(new String[] {browser, url});
}
}
catch (Exception e) {
JOptionPane.showMessageDialog(null, "Error in opening browser" + ":\n" + e.getLocalizedMessage());
}
}
Unfortunately, I don't understand what this does, or how to change it to my needs.
If possible could you explain your solution so that I can understand how it works? Thanks.

You can use Desktop class which allows Java applications to interact with default applications associated with specific file types on the host platform. Here you have a tutorial on How to integrate with the Desktop class.
Remember:
Use the isDesktopSupported() method to determine whether the Desktop
API is available
I made a quick example.
import java.awt.Desktop;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
public class DesktopTest {
private JPanel panel;
public DesktopTest() {
panel = new JPanel();
ActionListener listener = new OpenUrLAction();
JButton googleButton = new JButton("google");
googleButton.setActionCommand("http://www.google.com");
googleButton.addActionListener(listener);
JButton stackOverButton = new JButton("stackOverflow");
stackOverButton.setActionCommand("http://www.stackoverflow.com");
stackOverButton.addActionListener(listener);
panel.add(googleButton);
panel.add(stackOverButton);
}
public JPanel getPanel() {
return panel;
}
private class OpenUrLAction implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
if (Desktop.isDesktopSupported()) {
try {
Desktop desktop = Desktop.getDesktop();
desktop.browse(new URI(e.getActionCommand()));
} catch (IOException | URISyntaxException e1) {
JOptionPane.showMessageDialog(null,
"An error happen " + e1.getMessage());
}
}
}
}
/**
* Create the GUI and show it. For thread safety, this method should be
* invoked from the event-dispatching thread.
*/
private static void createAndShowGUI() {
// Create and set up the window.
JFrame frame = new JFrame("DesktopExample");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.setLocationByPlatform(Boolean.TRUE);
frame.add(new DesktopTest().getPanel());
// Display the window.
frame.pack();
frame.setVisible(Boolean.TRUE);
}
public static void main(String[] args) {
// Schedule a job for the event-dispatching thread:
// creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
If you don't find this useful , you can find some workaround in this answer

SwingWorker setting a flag after finishing its work

I have put together an application that opens text files and allows users to edit them (eg: text editor)
Some text files can be arbitrarily large, so it would take some time to open them. I have added a progress bar to inform the user that stuff is actually happening, and am using a swing worker to perform the actual file loading, giving it a reference to a text area to dump all the text.
I also have a flag in the main application called isFileLoaded which is true if there's a file open, and false otherwise. Ideally, the swing worker should set that value after it finishes loading the file and doing any processing that it needs to do.
I have written the swing worker as a separate class, so it's not nested inside my main Frame class that holds all of the GUI logic, mainly because I do not like to define classes inside classes purely for aesthetic reasons. As such, I am currently passing a reference to the entire Frame to the swing worker and letting it set the value of the flag.
Is this a good way to do things? Are there better ways?

Consider rather adding a PropertyChangeListener which holds a reference to your Frame (an anonymous inner-class would be just fine for that matter) and which listens to the "state" property. The value of the event will be equal to StateValue.DONE when the SwingWorker has finished.
Here is a fully working example:
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.util.List;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JProgressBar;
import javax.swing.SwingUtilities;
import javax.swing.SwingWorker;
import javax.swing.SwingWorker.StateValue;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class TestSwingWorker {
private JProgressBar progressBar;
protected void initUI() {
final JFrame frame = new JFrame();
frame.setTitle(TestSwingWorker.class.getSimpleName());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JButton button = new JButton("Clik me to start work");
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
doWork();
}
});
progressBar = new JProgressBar(0, 100);
frame.add(progressBar, BorderLayout.NORTH);
frame.add(button, BorderLayout.SOUTH);
frame.pack();
frame.setVisible(true);
}
private boolean someFlag;
protected void doWork() {
SwingWorker<Void, Integer> worker = new SwingWorker<Void, Integer>() {
#Override
protected Void doInBackground() throws Exception {
for (int i = 0; i < 100; i++) {
// Simulates work
Thread.sleep(10);
publish(i);
}
return null;
}
#Override
protected void process(List<Integer> chunks) {
progressBar.setValue(chunks.get(chunks.size() - 1));
}
#Override
protected void done() {
progressBar.setValue(100);
progressBar.setStringPainted(true);
progressBar.setString("Done");
}
};
worker.getPropertyChangeSupport().addPropertyChangeListener("state", new PropertyChangeListener() {
#Override
public void propertyChange(PropertyChangeEvent evt) {
if (StateValue.DONE.equals(evt.getNewValue())) {
someFlag = true;
}
}
});
worker.execute();
}
public static void main(String[] args) throws ClassNotFoundException, InstantiationException, IllegalAccessException,
UnsupportedLookAndFeelException {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new TestSwingWorker().initUI();
}
});
}
}

You should restructure your code a little to avoid using the whole Frame which indeed is not really clean (but if it works who cares).
If you want to be more cool from a design point of view you should use a model:
class FileModel
{
boolean isLoading;
// getter and setter that notifies
}
and pass only this model to your worker, and once done set the flag.

Opening edrawingsviewer files from java

I have an application that I run on a pc with a mouse, I want to launch edrawingsviewer with a particular file name from java and then when the user returns to the fullscreen app, if they haven't closed it I want to close it. This is what I've got so far for a quick demo but I cannot figure out what to put in the arguments in order to launch solidworks with a particular file.
package com.protocase.hmiclient.edrawings;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.io.FilenameFilter;
import java.io.IOException;
import javax.swing.JButton;
import javax.swing.JFrame;
/**
* #author DavidH
*/
public class EDrawingHelper {
public static File[] getEDrawingsForJob(final String jobNumber) {
File f = new File("\\\\itsugar\\www\\HMI\\POD EDRAWINGS");
File[] matchingFiles = f.listFiles(new FilenameFilter() {
public boolean accept(File dir, String name) {
return name.startsWith(jobNumber) && (name.endsWith("EASM") || name.endsWith("EDRW"));
}
});
return matchingFiles;
}
public static void test(String[] args) {
File[] files = getEDrawingsForJob("G080111004-13162-1");
for (File file : files){
System.out.println(file.getName());
}
}
public static void openEDrawingForFileName(String fileName){
try {
final Process process = Runtime.getRuntime().exec("C:\\Program Files\\SolidWorks Corp\\SolidWorks eDrawings (2)\\EModelViewer.exe \\\\itsugar\\www\\HMI\\POD EDRAWINGS\\"+fileName);
JFrame frame = new JFrame();
JButton killButton = new JButton("KILL");
killButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
process.destroy();
System.exit(0);
}
});
frame.getContentPane().add(killButton);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
} catch (IOException e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
openEDrawingForFileName("G080111004-13162-1 ASSEMBLY.EASM");
}
}
I don't think this is a solidworks problem, I think this is just something I'm passing wrong or formatting wrong or something.

It appears as if running it through the FileProtocolHandler causes it to open fine.
final Process process = Runtime.getRuntime().exec("rundll32 url.dll,FileProtocolHandler \\\\itsugar\\www\\HMI\\POD EDRAWINGS\\"+fileName);

Progress bar in Swing (Java) for command tools

I have several C/C++ command line tools that I'm wrapping with Java.Swing as GUI. The command line tools can take minutes to hours. Progress bar seems like a good idea to keep users sane. I'm also thinking it might be nice to wrap a GUI for the progress bar, instead of just using system out. But how?
I'm thinking the command line tools can write percents to stderr and I can somehow read it in java. Not exactly sure what the mechanics for this would be. I'm also not clear on asynchronous display (learned a bit about invokeLater() ). New to Java, and would appreciate general suggestions as well. Thanks.
--- update ---
Thanks everyone for your suggestions. Here's the resulting code.
private void redirectSystemStreams() {
OutputStream out_stderr = new OutputStream() {
#Override
public void write(final int b) throws IOException {
update(String.valueOf((char) b));
}
#Override
public void write(byte[] b, int off, int len) throws IOException {
update(new String(b, off, len));
}
#Override
public void write(byte[] b) throws IOException {
write(b, 0, b.length);
}
};
System.setErr(new PrintStream(out_stderr, true));
}
private void update(final String inputText) {
int value = 20; //parse inputText; make sure your executable calls fflush(stderr) after each fprintf().
jProgressBar.setValue(value);
/* Also one can redirect to a textpane
SwingUtilities.invokeLater(new Runnable() {
public void run() {
//update jTextPane with inputText
}
});
*/
}

That's seems very fragile, better would be to communicate via sockets in a well established protocol or with some sort of RCP ( perhaps Google's protobuf ) or even webservices.
If you still insists you can launch a process in Java with ProcessBuilder that will give you a Process reference of which you can get the InputStream to read the standard output, but again, that seems very fragile to me.
I hope this helps.

For the progress bar part of your problem you can do something like the following. Note that this is just an example to illustrate the point.
Basically, a thread is created to do the work. Presumably this Runner thread will be interacting with your C/C++ code to get its progress. It then calls update on the Progress Bars Dialog class.
import java.awt.BorderLayout;
import java.awt.Dimension;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JProgressBar;
public class Main {
private int value;
private Progress pbar;
public static void main(String args[]) {
new Main();
}
public Main() {
pbar = new Progress();
Thread t = new Thread(new Runner());
t.start();
}
class Progress extends JDialog {
JProgressBar pb;
JLabel label;
public Progress() {
super((JFrame) null, "Task In Progress");
pb = new JProgressBar(0, 100);
pb.setPreferredSize(new Dimension(175, 20));
pb.setString("Working");
pb.setStringPainted(true);
pb.setValue(0);
label = new JLabel("Progress: ");
JPanel panel = new JPanel();
panel.add(label);
panel.add(pb);
add(panel, BorderLayout.CENTER);
pack();
setVisible(true);
}
public void update(){
pb.setValue(value);
if(value >= 100){
this.setVisible(false);
this.dispose();
}
}
}
class Runner implements Runnable {
public void run() {
for (int i = 0; i <= 100; i++) {
value++;
pbar.update();
try {
Thread.sleep(50);
} catch (InterruptedException e) {
}
}
}
}
}

// Create a window
JFrame frame = new JFrame("Progress");
// Creates a progress bar and add it to the window
JProgressBar prog = new JProgressBar();
frame.add(prog);
// Run C/C++ application
try {
Process p = Runtime.getRuntime().exec(new String[]{"filename","arg1","arg2","..."});
// Get InputStream
BufferedReader br = new BufferedReader(new InputStreamReader(p.getInputStream()));
// Update the progress when recieving output from C/C++
new java.util.Timer().schedule(new TimerTask(){
public void run(){
String str = "";
while ((str=br.readLine()!=null) {
prog.setValue(new Integer(str)); // Set Value of Progress Bar
prog.setString(str+"%"); // Set Value to display (in text) on Progress Bar
}
}
},0,100); // Check every 100 milliseconds
// Fit the window to its contents and display it
frame.pack();
frame.setVisible(true);
} catch (Exception e) {
System.out.println("Failed To Launch Program or Failed To Get Input Stream");
}