Develop Reference

Codename one new gui builder-back command from EVERY form navigation

I am navigating between forms in the NEW GUI builder. The old one had a back button on every form by default.
How do I enable the back button on new gui builder in every form, every time i navigate in a new form? Tried through constants in theme.res. It is still not enabled by default.
Furthermore, is the method "new form1.show" the best way to navigate between forms ? (see code)
Assuming name files:
Main.java, myapplication.java, Form1 ,Form2 ,Form3
Code for navigation, assuming names button1 and Form3:
public void onbutton1ActionEvent(com.codename1.ui.events.ActionEvent ev) {
new Form3().show();
}
Back command from old gui builder, not working here:
public Form showForm(String resourceName, Command sourceCommand) {
try {
Form f = (Form)formNameToClassHashMap.get(resourceName).newInstance();
Form current = Display.getInstance().getCurrent();
if(current != null && isBackCommandEnabled() && allowBackTo(resourceName)) {
f.putClientProperty("previousForm", current);
setBackCommand(f, new Command(getBackCommandText(current.getTitle())) {
public void actionPerformed(ActionEvent evt) {
back(null);
}
});
}
if(sourceCommand != null && current != null && current.getBackCommand() == sourceCommand) {
f.showBack();
} else {
f.show();
}
return f;
} catch(Exception err) {
err.printStackTrace();
throw new RuntimeException("Form not found: " + resourceName);
}
}
I've tried:
form.setBackCommand(cmd);
public Command setBackCommand(String title, ActionListener<ActionEvent> listener)
public void setBackCommand(Command cmd)
public Command setBackCommand(String title, BackCommandPolicy policy, ActionListener<ActionEvent> listener)
public void setBackCommand(Command cmd, BackCommandPolicy policy)
boolean onBack() {
return true;
}
https://www.codenameone.com/blog/toolbar-back-easier-material-icons.html
on main.java and myapplication.java did not accept the commands.
Form3.getToolbar().setBackCommand("", e -> Form3.showBack());
althouth is should not work only for form3, but every form.
Did not work either. Putting "back command" on every sidemenu would not be the ideal solution, because we might be navigating to each form from different forms.
EXTRA:
Is there a way to enable global toolbar and global commands for all forms, so i do not copy paste the toolbar code for each new form? If not answered here, i might make a new thread.
Thanks.

The old GUI builder handled navigation as it was designed at a time when Nokia was the worlds leader in the mobile phone industry and a 4in device was considered large. Back then we assumed the UI was simpler for each form and the navigation was the hard part.
This changed. But the bigger problem for most developers was the concept of stateless navigation which triggered a lot of issues both in design and functionality.
The new GUI builder doesn't include any navigation code or any global code. Each form stands on its own.
Having said that you can implement your own state machine by just keeping form instances and showing the form you want to navigate to e.g.:
public static class Controller {
private static Form1 f1;
private static Form2 f2;
public static void showF1() {
if(f1 == null) f1 = new Form1();
f1.show();
}
// etc...
}
I used static context for simplicity but you can implement your own strategy. Notice that you can also insert global logic here e.g. add the toolbar as a function like:
private static void initForm(Form f) {
// add global commands to the toolbar
}
Alternatively you can derive all the forms from a common base class as the new GUI builder doesn't restrict your inheritance.

How to detect keypress

I am using java and trying to write a simple sudo mouse recorder that will store the mouse position when the space key is pressed. The only key I need to detect is the space key (Although if another key is easier, that will work).
I need the whole mouse recorder to be written in java, but it is OK if the function for the keypress is in another language. And I will be runing this in Windows 7.
What is the simplest way to do what has been described? All of the methods I have found require at minimum 20 lines of code. This is OK, except I don't understand how to implement them. I have an example source below:
import java.awt.MouseInfo;
import javax.swing.JOptionPane;
public class MouseRecorder {
public static void main (String[] args)
{
int slot = 0;
int xLoc[10];
int yLoc[10];
while (slot <= 10)
{
if (keyPressed(KEY_SPACE)) //<<<<This obviously won't work, but I'm looking for the simplest way to code this
{
xLoc[slot] = MouseInfo.getPointerInfo().getLocation().x;
yLoc[slot] = MouseInfo.getPointerInfo().getLocation().y;
slot++;
}
}
//The mouse information can now be utilized
}
}

Again your question is not clear since you have not addressed my comment:
It smells like to me that you might want a system-wide key logger that only responds to one key press, and that doesn't need a GUI. If this is so, then your best solution is to not use Java to create your application but to use a tool that can get closer to the OS. AutoIt comes to mind if this is for a Windows project. Please define your needs better.
and this forces us to guess at the problem and its solution.
If you are interested in creating a Swing GUI, having it take focus, and have it listen to key events, then the solution is to do this:
Create your Swing GUI and display it, leaving it as the active windowed application while your application is running.
Using Key Bindings have it listen for space bar presses
And then log the mouse location when the space bar is pressed.
As noted, this will not be achievable in 5 lines of code, so put that idea to the side.
If on the other hand your desire is to not have a GUI but rather listen for hot-key presses while any and all applications are running, then
The possible platforms used will be critical since your solution will require OS-specific code since creating a hot-key means having to create a keyboard handler routine, often in C, and doing this for each platform, and then linking it in to Java using JNI or JNA.
Or as noted another way is to link your Java program with an OS specific utility program or script such as AutoIt.
If you need more specific help, then please clarify your question.
Edit
You state:
Thank you for the answer, but as I have described above: "Changing languages is out of the question although it seems like that might be easier." and "I dont want a gui, if I can avoid it"
Then my second answer is what you're looking for. How adept are you at C/C++, JNI or JNA, and how good is your knowledge of operating system libraries? If you want a Java only solution, I would consider your requirements far above beginner or intermediate Java and into the realm of advanced -- or at least beyond my abilities at the moment, although I am sure that I could come up with some solutions after several days to a week or two of study.
... or consider getting rid of your "changing languages" requirement and instead allow at least meshing Java together with a scripting utility, like AutoIt. That could allow creation of solutions in a shorter period of time, at least for me. A limitation though is that these would be platform specific solutions. What is your purpose behind all of this? Could this be an XY problem in disguise?
Edit 2
I decided to try to solve this with a small AutoIt utility that I meshed with Java, and this is what I came up with.
My AutoIt program is called CaptureHotKey.au3, and it is compiled to an exe before use:
$key = $CmdLine[1]
HotKeySet($key, "hotKeyFunction")
While 1
Sleep(100)
WEnd
Func hotKeyFunction()
ConsoleWrite(#CRLF)
EndFunc
There's not much to it. All it does is set a hot-key from the first command line parameter, provides an endless while loop so that it will continue to run, and a hotkey function that is quite simple and only sends a carriage-return/line-feed to the console (which will be the standard output).
Then a Java class to help interact with this. It uses SwingPropertyLanguageSupport to allow addition of PropertyChangeListeners that respond on the Swing thread (in case I want to use this with a GUI).
import java.beans.PropertyChangeListener;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
import javax.swing.event.SwingPropertyChangeSupport;
public class CaptureHotKey implements Runnable {
public static final String HOT_KEY = "hot key";
private String hotKey;
private SwingPropertyChangeSupport pcSupport = new SwingPropertyChangeSupport(
this);
private Scanner scanner;
private CaptureHotKeyFromAutoIt capture;
public CaptureHotKey(final String hotKey) throws IOException {
this.hotKey = hotKey;
capture = new CaptureHotKeyFromAutoIt(hotKey);
scanner = new Scanner(capture.getReadable());
}
public void startCapturing() {
new Thread(this).start();
}
public void exit() {
if (capture != null) {
capture.exit();
}
if (scanner != null) {
scanner.close();
}
}
public void addPropertyChangeListener(PropertyChangeListener listener) {
pcSupport.addPropertyChangeListener(listener);
}
public void removePropertyChangeListener(PropertyChangeListener listener) {
pcSupport.removePropertyChangeListener(listener);
}
public String getHotKey() {
return hotKey;
}
#Override
public void run() {
while (scanner != null && scanner.hasNextLine()) {
scanner.nextLine();
pcSupport.firePropertyChange(HOT_KEY, true, false);
}
}
private static class CaptureHotKeyFromAutoIt {
public static final String AUTO_IT_APP_PATH = "CaptureHotKey.exe";
private Process process = null;
private ProcessBuilder pb;
public CaptureHotKeyFromAutoIt(String hotKey) throws IOException {
List<String> cmdList = new ArrayList<>();
cmdList.add(AUTO_IT_APP_PATH);
cmdList.add(hotKey);
pb = new ProcessBuilder(cmdList);
pb.redirectErrorStream(true);
process = pb.start();
}
public void exit() {
if (process != null) {
process.destroy();
}
}
public Readable getReadable() {
if (process != null) {
return new InputStreamReader(process.getInputStream());
}
return null;
}
}
}
Finally a Java class to test this set up:;
This adds a PropertyChangeListener to the class above to allow it to be notified if the hot-key is pressed:
import java.awt.MouseInfo;
import java.awt.PointerInfo;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.io.IOException;
import java.util.Scanner;
public class CaptureHotKeyTest {
public static final String CTRL_R = "^r"; // "{SPACE}" works for spacebar
private static final String EXIT = "exit";
private CaptureHotKey capture;
public CaptureHotKeyTest() {
try {
capture = new CaptureHotKey(CTRL_R);
capture.addPropertyChangeListener(new HotKeyPropertyChngListener());
capture.startCapturing();
Scanner scan = new Scanner(System.in);
System.out.println("Press control-r to get mouse position.");
System.out.println("Type \"exit\" to exit program");
while (scan.hasNextLine()) {
String line = scan.nextLine();
if (line.equalsIgnoreCase(EXIT)) {
scan.close();
capture.exit();
break;
}
}
} catch (IOException e) {
e.printStackTrace();
}
}
private class HotKeyPropertyChngListener implements PropertyChangeListener {
#Override
public void propertyChange(PropertyChangeEvent evt) {
if (evt.getPropertyName().equals(CaptureHotKey.HOT_KEY)) {
System.out.println("hot key pressed");
PointerInfo pointerInfo = MouseInfo.getPointerInfo();
System.out.println("Mouse: " + pointerInfo.getLocation());
}
}
}
public static void main(String[] args) {
new CaptureHotKeyTest();
}
}

You should use KeyListener: http://docs.oracle.com/javase/tutorial/uiswing/events/keylistener.html
It works fine with Swing

java stop people from closing

hi i have a full screen program which i dont want people to close unless they have a password i have this code at the moment
public void windowClosing(WindowEvent arg0)
{
System.out.println("HERE");
String inputValue = JOptionPane.showInputDialog("Please input the closeword");
if (inputValue != "closeplz")
{
}
}
in the if statement i want it to stop the method so that the program doesent close. any help would be greatly aprecheated thanks ste

You have to call
setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
on (or within) the JFrame instance. Then the frame will not close unless you do it manually, though windowClosing() will still be called. Inside it, you can then conditionally call
System.exit(1);
which will end the application. Be sure to do any necessary cleanup first.

Check out Closing an Applicaton for a simple class to help you with this. You would need to provide the custom close action that prompts the user for the password.
Using your simple example the code would be:
Action ca = new AbstractAction()
{
public void actionPerformed(ActionEvent e)
{
JFrame frame = (JFrame)e.getSource();
String inputValue = JOptionPane.showInputDialog("Please input the closeword");
if (! inputValue.equals("closeplz"))
{
frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
}
}
};
CloseListener cl = new CloseListener(ca);

java form button order execution

i write a method to create a form(3 buttons and a textBox), then i call it in main.
but when i run program, before i enter information in the form (method form6 ),
Other commands that are executed! "s4 and ontname chenged in the form".
this is a part of my code:::::::::::
//////////////////////////////////////////////////////////////////////////
public static void main(String[] args) {
System.out.println("*begin main*"); // call form method
String s4= form6(); // s4 is returned by method.
System.out.println("s3333*"+s4);
System.out.println("ont:"+ontname);//it's global }
//////////////////////////////////////////////////////////////////////////
i have 2 questions:::
1--- While the form is running, other commands are executed!
What is their order execution?
2. --- i want to define a button to when i click it,it closes the form.
thanks all.

If I get your code correctly, ontname is either (1) a class member (declared outside a method) or (2) a local variable, which is declared in the method that contains this code snippet.
In both cases there is no need to "return" ontname just because it is not declared inside the anonymous ActionListener instance.
The following example illustrates a typical pattern for this problem:
public void someMethod() {
// ...
button2.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
String filename = File.separator+"c:";
JFileChooser fc = new JFileChooser(new File(filename));
fc.showOpenDialog(null);
File selFile = fc.getSelectedFile();
setOntName(selFile.getPath()); // <-- here we call another method
}
});
// ...
}
void setOntName(String ontName) {
// do something with ontName
}
Alternativly: declare ontName as a static class member (only):
private static String ontName = ""; // <-- accessible from main method
public static void main(String[] args) {
// ...
}
// more methods.

You can't return a value in this Method because the ActionListenerInterface does not allow this. But you can call another method from within the actionPerformed() method and pass the ontname to it.
You can also close the third button in the new method. Or define the third button as final and use it in the actionPerformed() method.
E.g.
button2.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
String filename = File.separator+"c:";
JFileChooser fc = new JFileChooser(new File(filename));
fc.showOpenDialog(null);
File selFile = fc.getSelectedFile();
ontname=selFile.getPath();
System.out.println("filepath: "+ontname); //it works correctly.
anotherMethod(ontname);
}
});
private void anotherMethod(String path) {
//doSomething with the path
//close third button here
}

You could probably define your variable ontname as global, outside of your function:
var ontname = null;
button2.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
// ...
ontname=selFile.getPath();
}
});
// ...
System.out.println("filepath: "+ontname);

If you want to remember the values, then they should be class level variables.
But, generally, you would want to pass these to some other method to do some processing on them (or, say, persist them in a file). You can pass these as parameters to the other method.
(The second one is better in most cases, I don't know much about your app, so I am unable to give one answer)
There are other problems with your code:
You need to check whether the use has clicked the "Ok" or "Cancel" button in the open dialog to decide whether to get the file or not.
String filename = File.separator+"c:"; does not really make sense. Perhaps you meant String filename = "c:"+File.separator; But even this is not very useful. File.separator is for getting the platform specific file separator char (\ in Windows, / on linux) but since you are hard coding c:, you are anyway constrainting your app to Windows. You might want to have a better platform independent way (start at the "default" path, new JFileChooser() without arguments, and then remember the path the user last used, and proceed from there)
If the argument to the showOpenDialog method is your parent frame, then the dialog would be centered on the parent frame, and would, in most cases, look nicer.
You might also want to relook your variable names.
button2.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
String filename = File.separator+"c:";
JFileChooser fc = new JFileChooser(new File(filename));
int option = fc.showOpenDialog(null);
if(option = JFileChooser.APROVE_OPTION)
{
File selFile = fc.getSelectedFile();
String ontname=selFile.getPath();
System.out.println("filepath: "+ontname); //it works correctly.
doSomeOperation(ontname); //Or, declare ontname as a class level variable.
}
}
});

Java - Console-like web applet [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
We don’t allow questions seeking recommendations for books, tools, software libraries, and more. You can edit the question so it can be answered with facts and citations.
Closed 4 years ago.
Improve this question
Hey, I've been developing an application in the windows console with Java, and want to put it online in all of its console-graphics-glory.
Is there a simple web applet API I can use to port my app over?
I'm just using basic System.out and System.in functionality, but I'm happy to rebuild my I/O wrappers.
I think something along these lines would be a great asset to any beginning Java developers who want to put their work online.

Sure, just make into an applet, put a small swing UI on it with a JFrame with two components - one for writing output to, and one for entering inputs from. Embed the applet in the page.

I did as Lars suggested and wrote my own.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
import java.awt.Font;
public class Applet extends JFrame {
static final long serialVersionUID = 1;
/** Text area for console output. */
protected JTextArea textArea;
/** Text box for user input. */
protected JTextField textBox;
/** "GO" button, in case they don't know to hit enter. */
protected JButton goButton;
protected PrintStream printStream;
protected BufferedReader bufferedReader;
/**
* This function is called when they hit ENTER or click GO.
*/
ActionListener actionListener = new ActionListener() {
public void actionPerformed(ActionEvent actionEvent) {
goButton.setEnabled(false);
SwingUtilities.invokeLater(
new Thread() {
public void run() {
String userInput = textBox.getText();
printStream.println("> "+userInput);
Input.inString = userInput;
textBox.setText("");
goButton.setEnabled(true);
}
}
);
}
};
public void println(final String string) {
SwingUtilities.invokeLater(
new Thread() {
public void run() {
printStream.println(string);
}
}
);
}
public void printmsg(final String string) {
SwingUtilities.invokeLater(
new Thread() {
public void run() {
printStream.print(string);
}
}
);
}
public Applet() throws IOException {
super("My Applet Title");
Container contentPane = getContentPane();
textArea = new JTextArea(30, 60);
JScrollPane jScrollPane = new JScrollPane(textArea);
final JScrollBar jScrollBar = jScrollPane.getVerticalScrollBar();
contentPane.add(BorderLayout.NORTH, jScrollPane);
textArea.setFocusable(false);
textArea.setAutoscrolls(true);
textArea.setFont(new Font("Comic Sans MS", Font.TRUETYPE_FONT, 14));
// TODO This might be overkill
new Thread() {
public void run() {
while(true) {
jScrollBar.setValue(jScrollBar.getMaximum());
try{
Thread.sleep(100);
} catch (Exception e) {}
}
}
}.start();
JPanel panel;
contentPane.add(BorderLayout.CENTER, panel = new JPanel());
panel.add(textBox = new JTextField(55));
textBox.addActionListener(actionListener);
panel.add(goButton = new JButton("GO"));
goButton.addActionListener(actionListener);
pack();
// End of GUI stuff
PipedInputStream inputStream;
PipedOutputStream outputStream;
inputStream = new PipedInputStream();
outputStream = new PipedOutputStream(inputStream);
bufferedReader = new BufferedReader(new InputStreamReader(inputStream, "ISO8859_1"));
printStream = new PrintStream(outputStream);
new Thread() {
public void run() {
try {
String line;
while ((line = bufferedReader.readLine()) != null) {
textArea.append(line+"\n");
}
} catch (IOException ioException) {
textArea.append("ERROR");
}
}
}.start();
}
}
This below code was in a separate class, "Input", which has a static "inString" string.
public static String getString() {
inString = "";
// Wait for input
while (inString == "") {
try{
Thread.sleep(100);
} catch (Exception e) {}
}
return inString;
}
Through-out the lifespan of the project I will probably maintain this code some more, but at this point - it works :)

As a premier example of a glorious and incredibly useful cnsole-like webapp, please see goosh, the Google Shell. I cannot imagine browsing the Net without it anymore.
Granted, there's no source code, but you might get out a bit of its magic by using Firebug or so.
Using a TextArea might be a bug-prone approach. Remember that you'll need to do both input and output to this TextArea and that you must thus keep track of cursor position. I would suggest that, if you really do this approach, you abstract away over a plain TextArea (inheritance, maybe?) and use a component that has, e.g. a prompt() to show the prompt and enable input and a also follows the usual shell abstraction of having stdin (an InputStream, that reads from the prompt, but can be bound to, let's say files or so) and stdout and possibly stderr, OutputStreams, bound to the TextArea's text.
It's not an easy task, and I don't know of any library to do it.

I remember seenig telnet client applet implementationa around years ago (back when people used telnet). Maybe you could dig them out and modify them.

System.out and System.in are statics and therefore evil. You'll need to go through your program replacing them with non-statics ("parameterise from above"). From an applet you can't use System.setOut/setErr/setIn.
Then you're pretty much sorted. An applet. Add a TextArea (or equivalent). Append output to the text area. Write key strokes to the input. Job done.