Develop Reference

setVisible in Table in libgdx not working?

I have the following problem:
I am trying to implement a menu with submenus in libgdx, using the table layout. When a submenu is clicked, a listener is fired, which should setVisible(false) the previous menu, and setVisible(true) the new one. But, although I successfully display the new one, the previous one is still here! Could someone help me?
Here is my code:
The Menu.java:
public class Menu extends Table {
private Stage stage;
public void attachToStage(Stage s) {
if (s != null) {
stage = s;
s.addActor(this);
}
}
public Menu() {
this(null);
}
public Menu(final Stage s) {
attachToStage(s);
setFillParent(true);
top();
left();
}
private void addButtonWithListener(String label, ClickListener listener) {
add().width(10);
Label l = new Label(label, SkinManager.get());
add(l).width(100);
row();
if (listener != null)
l.addListener(listener);
}
/**
* #param label
* #return The menu, for chaining
*/
public Menu addButton(String label) {
addButtonWithListener(label, null);
return this;
}
/**
*
* #param label
* #param m
* the menu to add
* #return The main menu, for chaining
*/
public Menu addMenu(String label, final Menu m) {
addButtonWithListener(label, new ClickListener() {
#Override public void clicked(InputEvent e, float x, float y) {
System.out.println(getChildren());
setVisible(false);
m.setVisible(true);
}
});
m.attachToStage(stage);
m.setVisible(false);
return this;
}
}
My Application:
public class TestApplication implements ApplicationListener {
private Stage stage;
#Override public void create() {
stage = new Stage();
Menu m = new Menu(stage).addButton("Move").addButton("Stay");
m.addMenu("Attack", new Menu().addButton("Sword").addButton("Bow"));
Gdx.input.setInputProcessor(stage);
}
#Override public void render() {
stage.draw();
}
// Other empty methods
}
Thanks a lot!
EDIT: Problem was unrelated, see my answer

Ok, found the problem: not related at all to the Table, just forgott to clear the screen in the Application.
I just added
Gdx.gl.glClearColor(0, 0, 0, 0);
Gdx.gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
in the render function.

Call JavaFX application twice

I would need help with the following: I am implementing an application in javafx, this application Is called through a click on a button.
The problem is that when I close the application then I can not call it again.
I have read that you can not call the Application.launch() method more than once.
But I found something on the service class. The examples in the documentation page are not very clear. Anyone have an idea of ​​how this could be done?
Thank you.
http://docs.oracle.com/javafx/2/threads/jfxpub-threads.htm
my code:
private void jButton1ActionPerformed (java.awt.event.ActionEvent evt) {
WebMap n1 = new WebMap () / / application in javafx
n1.Lunch ();
}
WebMap class: / / javafx application
public void Lunch () {
Application.launch ();
}

You can't launch a JavaFX application more than once in the same process, so don't try to do that.
You need to find an alternative mechanism to do whatever it is you are trying to do.
If you are embedding JavaFX scenes in a Swing application you should be creating new JFXPanels in Swing, not creating new JavaFX Applications on Swing button presses.
If you are intending to have a pure JavaFX application, then there is no need to have a Swing button which launches a JavaFX application, you can just use a JavaFX button instead and directly display the JavaFX scene.
There is no need to use a Service in this case, Service is used for performing repeated background tasks on a another thread, which has nothing to do with what you are attempting.
Read JavaFX for Swing developers if you want to integrate a Swing and JavaFX application.

As a committer of the com.bitplan.javafx open source project I can point you to the work-around we have been using for a while now:
https://github.com/BITPlan/com.bitplan.javafx/blob/master/src/main/java/com/bitplan/javafx/WaitableApp.java
WaitableApp.toolkitInit();
will initialize the JavaFX environment.
https://github.com/BITPlan/com.bitplan.javafx/blob/master/src/main/java/com/bitplan/javafx/SampleApp.java
will show an example of how the WaitableApp base class is used in general. You also might want to have a look at the Junit Testcases of the project.
WaitableApp
/**
* Waitable Application that does not need launch
*
* #author wf
*
*/
public abstract class WaitableApp extends Application {
protected Stage stage;
static boolean toolkitStarted;
/**
* allow startup without launch
*/
#SuppressWarnings("restriction")
public static void toolkitInit() {
if (!toolkitStarted) {
toolkitStarted = true;
// do not exit on close of last window
// https://stackoverflow.com/a/10217157/1497139
Platform.setImplicitExit(false);
/// https://stackoverflow.com/a/38883432/1497139
// http://www.programcreek.com/java-api-examples/index.php?api=com.sun.javafx.application.PlatformImpl
com.sun.javafx.application.PlatformImpl.startup(() -> {
});
}
}
#Override
public void start(Stage stage) {
this.stage = stage;
}
public Stage getStage() {
return stage;
}
public void setStage(Stage stage) {
this.stage = stage;
}
/**
* wait for close
*
* #throws InterruptedException
*/
public void waitStatus(boolean open) {
int sleep = 1000 / 50; // human eye reaction time
try {
if (open)
while ((stage == null) || (!stage.isShowing())) {
Thread.sleep(sleep);
}
else
while (stage != null && stage.isShowing()) {
Thread.sleep(sleep);
}
} catch (InterruptedException e) {
ErrorHandler.handle(e);
}
}
public void waitOpen() {
waitStatus(true);
}
public void waitClose() {
waitStatus(false);
}
/**
* show me
*/
public void show() {
// ignore multiple calls
if (stage != null)
return;
Platform.runLater(() -> {
try {
this.start(new Stage());
} catch (Exception e) {
ErrorHandler.handle(e);
}
});
}
/**
* close this display
*/
public void close() {
Platform.runLater(() -> {
if (stage != null)
stage.close();
});
this.waitClose();
// allow reopening
stage = null;
}
}

Java swing - when cancel button clicked don't loop

I have a gui, that is having a Login prompt added.
while(notValidLogIn){
LoginPrompt.getDetails() //a static method that
}
Hwoever, the loginPrompt is a Jdialog, with a parent JFrame. How can I stop looping of cancel clicked, I could put System.exit(0) in cancel action performed. But don't want to stop everything, I want something like :
while(notValidLogIn && LoginPrompt.isNotCancelled()){
LoginPrompt.getDetails(); //a static method that creates an instance of login JDialog()
}

In a recent project I was working on, I've implemented an event based solution. The idea is JDialog notify to its parent JFrame how the login process went and this last one may or may not continue its execution. This way I have no loops and keep separate responsibilities: The schema would be something like this:
LoginEvent:
This is the event itself. Not that complicated:
class LoginEvent extends EventObject {
public static final int LOGIN_SUCCEEDED = 0;
public static final int LOGIN_FAILED = 1;
public static final int LOGIN_DIALOG_CLOSED = 2;
private int id;
public LoginEvent(Object source, int id) {
super(source);
this.id = id;
}
public int getId() {
return id;
}
}
LoginListener
An interface to handle these LoginEvents:
public interface LoginListener extends EventListener {
public void handleLoginEvent(LoginEvent evt);
}
Login Dialog
This class has to mantain a List with subscribed LoginListeners:
class LoginDialog {
List<LoginListener> listeners = new ArrayList<>();
JDialog dialog;
JButton accept;
JButton cancel;
public void show() {
//create and show GUI components
}
public void close() {
if(dialog != null) {
dialog.dispose();
}
}
...
public void addLoginListener(LoginListener loginEventListener) {
if(!listeners.contains(loginEventListener)) {
listeners.add(loginEventListener);
}
}
public void removeLoginListener(LoginListener loginEventListener) {
listeners.remove(loginEventListener);
}
public void dispatchLoginEvent(LoginEvent evt) {
for(LoginListener loginListener: listeners) {
loginListener.handleLoginEvent(evt);
}
}
}
Adding action listeners to accept and cancel buttons:
accept.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
// validate login data
if(loginValid) {
dispatchLoginEvent(new LoginEvent(dialog, LoginEvent.LOGIN_SUCCEEDED));
} else {
dispatchLoginEvent(new LoginEvent(dialog, LoginEvent.LOGIN_FAILED));
}
}
});
cancel.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
dispatchLoginEvent(new LoginEvent(dialog, LoginEvent.LOGIN_DIALOG_CLOSED));
}
});
Subscribing a LoginListener
In your JFrame:
final LoginDialog dialog = new LoginDialog();
dialog.addLoginListener(new LoginListener() {
#Override
public void handleLoginEvent(LoginEvent evt) {
if(evt.getId() == LoginEvent.LOGIN_SUCCEEDED {
dialog.close();
//continue execution
return;
}
if(evt.getId() == LoginEvent.LOGIN_FAILED) {
JOptionPane.showMessageDialog(null, "Login failed!");
return;
}
if(evt.getId() == LoginEvent.CLOSE_LOGIN_DIALOG) {
dialog.close();
// do something when this dialog is closed
}
}
};
dialog.show();

while(notValidLogIn && LoginPrompt.isNotCancelled()){
LoginPrompt.getDetails(); //a static method that creates an instance of login JDialog()
}
If this loop is inside another thread other than the EDT(event dispatch thread), then you can use SwingUtilities.invokeAndWait(new Runnable()) function: invokeAndWait() blocks the current thread until the EDT is done executing the task given by it. This option is particularly used while we want to await an execution of a thread for taking confirmation from user or other input using JDialogue/JFileChooser etc
while(notValidLogIn && LoginPrompt.isNotCancelled()){
SwingUtilities.invokeAndWait(new Runnable() {
public void run() {
LoginPrompt.getDetails() ;
}
});
}
Note: re-stating for emphasizing: you should ensure that this loop is executing inside another Thread: such as using an extended class of Runnable, or by means of anonymous class:
new Thread()
{
// other code of your context
public void run()
{
while(notValidLogIn && LoginPrompt.isNotCancelled()){
SwingUtilities.invokeAndWait(new Runnable() {
public void run() {
LoginPrompt.getDetails() ;
}
});
}
}
}.start();

Outer Class Member Variable Null To Inner Class

I am working on a game using JME3 and Nifty GUI. I have an outer class that has a Nifty member variable. And the inner class should be able to access that variable regardless of access modifier. In the constructor I assign a new Nifty object to it. However when I access that variable in the inner class I run into problems. I did a little debugging and found out it's because the inner class thinks the Nifty member variable is null and I cant figure out why. Its not null in the outer class. Since this is a JME3 game I tried to have the inner class implement the AppState interface but it still shows the Nifty member variable as null. Here is the code:
public class MenuScreen extends SimpleApplication {
/** Used to configure Nifty GUI. */
private Nifty mNifty;
private NiftyJmeDisplay mNiftyDisplay;
private Element popup;
//*******************
// Overridden medhods
//*******************
/** This method is used to initialize everything needed to display the game screen. */
#Override
public void simpleInitApp() {
guiNode.detachAllChildren();
initNifty();
flyCam.setDragToRotate(true);
}
/**
* The game's main update loop.
*
* #param tpf Time Per Fram, the time it takes each loop to run.
*/
#Override
public void simpleUpdate(float tpf) {
// not used
}
#Override
public void simpleRender(RenderManager rm) {
// not used
}
public static void main(String[] args) {
MenuScreen app = new MenuScreen();
app.start();
}
/**
* Helper method to initialize and configure Nifty GUI.
*/
private void initNifty() {
mNiftyDisplay = new NiftyJmeDisplay(assetManager, inputManager, audioRenderer, guiViewPort);
mNifty = mNiftyDisplay.getNifty();
guiViewPort.addProcessor(mNiftyDisplay);
// If this is being run on a desktop then load the desktop main menu.
if (Strings.OS_NAME.contains("windows") || Strings.OS_NAME.contains("mac") || Strings.OS_NAME.contains("linux")) {
mNifty.fromXml("Interface/XML/DesktopMenuScreenGui.xml", "start", new MenuScreen().new MenuScreenGui());
}
// If its an Android device load the mobile main menu.
else if (Strings.OS_NAME.contains("android")) {
mNifty.fromXml("Interface/XML/MobileMenuScreenGui.xml", "mobile", new MenuScreen().new MenuScreenGui());
}
}
//**************
// Inner Classes
//**************
/**
* © Jason Crosby 2012 <p>
*
* This class handles all the GUI interactions like button clicks.
*
* #author Jason Crosby
*/
public class MenuScreenGui implements ScreenController, EventTopicSubscriber<MenuItemActivatedEvent>,
AppState {
#Override
public void initialize(AppStateManager stateManager, Application app) {
}
#Override
public void cleanup() {
}
#Override
public boolean isEnabled() {
return false;
}
#Override
public boolean isInitialized() {
return false;
}
#Override
public void postRender() {
}
#Override
public void setEnabled(boolean active) {
}
#Override
public void stateAttached(AppStateManager stateManager) {
}
#Override
public void stateDetached(AppStateManager stateManager) {
}
#Override
public void render(RenderManager rm) {
}
#Override
public void update(float tpf) {
}
#Override
public void bind(Nifty nifty, Screen screen) {
// not used
}
#Override
public void onEndScreen() {
// not used
}
#Override
public void onStartScreen() {
// not used
}
#Override
public void onEvent(String string, MenuItemActivatedEvent t) {
}
//**************
// Class methods
//**************
/**
* Called when the play button is clicked.
*/
public void playButton() {
}
/**
* Called when the high scores button is clicked.
*/
public void highScoresButton() {
}
/**
* Called when the settings button is clicked.
*/
public void settingsButton() {
}
public void quitButton() {
showDialog();
}
/**
* Called when the rate button is clicked. Only Available on mobile.
*/
public void rateButton() {
}
/**
* Called when the feedback button is clicked. Only on mobile devices.
*/
public void feedbackButton() {
}
/**
* Called when the help button is clicked.
*/
public void helpButton() {
}
/**
* Called when the dialog needs to be shown.
*/
public void showDialog() {
System.out.println("WWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW");
popup = new Nifty().createPopup("popup");
System.out.println("ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ");
//Menu myMenu = popup.findNiftyControl("#menu", Menu.class);
//myMenu.setWidth(new SizeValue("100px")); // must be set
//myMenu.addMenuItem("Click me!", new menuItem("menuItemid", "blah blah")); // menuItem is a custom class
//mNifty.subscribe(mNifty.getCurrentScreen(), myMenu.getId(), MenuItemActivatedEvent.class, this);
mNifty.showPopup(mNifty.getCurrentScreen(), popup.getId(), null);
}
public void clsoseDialog() {
}
/**
* Used to return a String to the Nifty xml file.
*
* #param name The name key associated with the String.
* #return The String associated with the key.
*/
public String getString(String name) {
if (name.equals("play")) {
return Strings.PLAY_BUTTON;
}
else if (name.equals("high_score")) {
return Strings.HIGH_SCORES_BUTTON;
}
else if (name.equals("settings")) {
return Strings.SETTINGS_BUTTON;
}
else if (name.equals("quit")) {
return Strings.QUIT_BUTTON;
}
else if (name.equals("rate")) {
return Strings.RATE_BUTTON;
}
else if (name.equals("feedback")) {
return Strings.FEEDBACK_BUTTON;
}
else if (name.equals("rules")) {
return Strings.RULES_BUTTON;
}
return null;
}
}
}
What happens is I click on the quit button which calls the quitButton() method. That works fine. That in turn invokes showDialog() which is where the problem is. In the showDialog() method is this line popup = new Nifty().createPopup("popup"); and it is at that line which mNifty is null when it shouldn't be. Any assistance is appreciated.

The line
popup = new Nifty().createPopup("popup");
does not use mNifty. It creates a new instance of Nifty and then calls creatPopup() on this new instance. Since earlier you initialized mNifty by calling what looks like a factory method
mNifty = mNiftyDisplay.getNifty();
it is quite possible that obtaining a Nifty via new does not return a completely initialized instance. Since you haven't posted the code for Nifty it is unclear what is happening.
I would double-check to make sure that creating a Nifty via new will return a fully initialized instance, and that you really wanted a new instance here.

Eclipse JFace's Wizards (Again ...)

Now that I am able to set the content of my second wizard's page depending on the first page selection, I am looking for a way to give the focus to my 2nd page's content when the user clicks the next button on the first page.
By default, when the user click the next button, the focus is given to the button composite (next, back or finish button depending on the wizard configuration)
The only way I found to give focus to my page's content is the following one:
public class FilterWizardDialog extends WizardDialog {
public FilterWizardDialog(Shell parentShell, IWizard newWizard) {
super(parentShell, newWizard);
}
#Override
protected void nextPressed() {
super.nextPressed();
getContents().setFocus();
}
}
To me it's a little bit "boring and heavy" to have to override the WizardDialog class in order to implement this behavior. More over, the WizardDialog javadoc says:
Clients may subclass WizardDialog, although this is rarely required.
What do you think about this solution ? Is there any easier and cleaner solution to do that job ?

This thread suggests:
In your wizard page, use the inherited setVisible() method that is called automatically before your page is shown :
public void setVisible(boolean visible) {
super.setVisible(visible);
// Set the initial field focus
if (visible) {
field.postSetFocusOnDialogField(getShell().getDisplay());
}
}
The postSetFocusOnDialogField method contains :
/**
* Posts <code>setFocus</code> to the display event queue.
*/
public void postSetFocusOnDialogField(Display display) {
if (display != null) {
display.asyncExec(
new Runnable() {
public void run() {
setFocus();
}
}
);
}
}

VonC's answer works great, I personally found it to be a little easier to work with like this though:
#Override
public void setVisible(boolean visible) {
super.setVisible(visible);
if (visible) {
Control control = getControl();
if (!control.setFocus()) {
postSetFocus(control);
}
}
}
private void postSetFocus(final Control control) {
Display display = control.getDisplay();
if (display != null) {
display.asyncExec(new Runnable() {
#Override
public void run() {
control.setFocus();
}
});
}
}