JOptionPane.showMessageDialog having to quit twice - java

So I have a JOptionPane that appears when a certain condition isn't met and for some reason when I press "Ok" it appears again, but then when pressing "Ok" on the second dialog it goes way.
Below is the method where the dialog gets made:
public boolean checkBet()
{
if(currentPlayer.getBet() <= 0)
{
JOptionPane.showMessageDialog(null, "You must place a bet before you can roll your dice!.",
"Bet Required!",
JOptionPane.ERROR_MESSAGE);
return false;
}
else
return true;
}
and this is where the above method gets called:
#Override
public void actionPerformed(ActionEvent e) {
checkBet();
if(checkBet())
{
setRollingPlayer(currentPlayer);
new Thread() {
#Override
public void run() {
gameEngine.rollPlayer(rollingPlayer, 500, 2000, 500);
}
}.start();
}
}

You're call checkBet twice in the actionPerformed method
#Override
public void actionPerformed(ActionEvent e) {
checkBet(); // Here
if(checkBet()) // And here
{

When you are calling function checkBet() in actionPerformed(), it has been mentioned two times. Function checkBet() will also execute inside if().
Remove calling once and it will execute once.

Related

How do I run loops while keeping events running?

I have a question about using events to run loops since doing so seems to lock down the thread. For example I have an nativeMousePressed and nativeMouseReleased event and I am trying to execute some code continuously while the mouse is pressed and then stop when its released. I tried to do this by creating a static boolean variable in another manager class and then setting it to true when the mouse is being pressed and false when the mouse is released. Then I decided to make a while loop that gets called from inside that nativeMousePressed event that uses the boolean value I talked about earlier. The issue is that no events can be called while that while loop is running which means the boolean value when never become false creating an infinite loop. How can I run the while loop while keeping the events running as well?
I assume this has to do with the thread being locked down but I have not worked with stuff like this much and would like some help figuring out how to run both these things in parallel.
public class NativeMouseEvent implements NativeMouseListener {
Program program = new Program();
#Override
public void nativeMouseClicked(org.jnativehook.mouse.NativeMouseEvent e) {
}
#Override
public void nativeMousePressed(org.jnativehook.mouse.NativeMouseEvent e) {
if(e.getButton() == 1 && Controller.threeClicked) {
Controller.fixAim = true;
program.start();
}
}
#Override
public void nativeMouseReleased(org.jnativehook.mouse.NativeMouseEvent e) {
program.interrupt();
Controller.fixAim = false;
}
}
Here is what my second thread is running...
public class Program extends Thread {
public void run() {
while(Controller.fixAim) {
System.out.println("test");
}
}
Here my second attempt which also gives me an error saying that this.program is null.
public class NativeMouseEvent implements NativeMouseListener {
Program program;
#Override
public void nativeMouseClicked(org.jnativehook.mouse.NativeMouseEvent e) {
}
#Override
public void nativeMousePressed(org.jnativehook.mouse.NativeMouseEvent e) {
if(e.getButton() == 1 && Controller.threeClicked) {
Controller.fixAim = true;
if(program != null) {
program = new Program();
program.start();
}
}
}
#Override
public void nativeMouseReleased(org.jnativehook.mouse.NativeMouseEvent e) {
program.interrupt();
program = null;
Controller.fixAim = false;
}
}
Start a tread on mouse down and stop the tread on mouse up. In the thread do circle drawing.
Something like below java code. Note: it is just an example. You need to make changes to make it work in your android environment.
public class Test {
Thread drawTask;
public void mouseDown() {
drawTask = new Thread(()-> {
int i = 0;
try {
for(;;) {
System.out.print("\rDrawing circle " + i++);
Thread.sleep(500);
}
} catch(InterruptedException e) {
System.out.println("finished drawing circle.");
}
});
drawTask.start();
}
public void mouseUp() {
if(drawTask != null) {
drawTask.interrupt();
drawTask = null; //<--- make sure you do this
}
}
public static void main(String[] args) {
Test test = new Test();
Scanner in = new Scanner(System.in);
System.out.println("type anything and press Enter to simulate mouse down/up");
in.next();
test.mouseDown();
in.next();
test.mouseUp();
in.next();
in.close();
}
}

java swing manual start an event without user input

I want to activate an event without clicking all the button interface.
ex. when i click button_0, it will print red, and at the same time it will perform action on button_1 and button_2, hence will also print blue and green at the same time.
Those three operation must be separate, solution as merging both action is not applicable on my case, I only made the example as a small guide.
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==button_0)
{
System.out.println("red");
}
else if(e.getSource()==button_1)
{
System.out.println("blue");
}
else if(e.getSource()==button_2)
{
System.out.println("green");
}
}
Here's a dirty way to do it:
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==button_0)
{
System.out.println("red");
button_1.doClick();
button_2.doClick();
}
else if(e.getSource()==button_1)
{
System.out.println("blue");
}
else if(e.getSource()==button_2)
{
System.out.println("green");
}
}

button event doesn't work properly

I have some doubts about the use of the methods wait() and notify(). I have the next code which has some button events, the first time the user pushes the button it has to stop printing, and the second time it restarts printing again. I understand that is better to use Runnable instead of Thread, but I have to use Thread because of the requirements. The code works fine the first time the button is pushed but the second time it doesn´t, I want to use the wait() and the notify, but i don´t know how to do it with this particular code.
class Thr extends Thread{
private int count = 0;
private long pause;
private boolean canPrint = true;
private JTextArea textArea;
Thr(long miliseconds,JTextArea text){
pause = miliseconds;
textArea = text;
}
public void pushedButton(){
if(canPrint)
this.canPrint = false;
else
this.canPrint = true;
}
public void run()
{
while(this.canPrint)
{
try
{
this.printCounter();
Thread.sleep(pause);
this.count++;
}
catch(InterruptedException e)
{
e.printStackTrace();
}
}
}
public void printCounter(){
String time;
time = Integer.toString(count);
textArea.setText(time);
}
}
class Interface extends JFrame implements ActionListener{
private JTextArea textArea,textArea2;
private JButton button;
private Thr thread,threadEvent;
Interface()
{
textArea = new JTextArea(10,7);
textArea2 = new JTextArea(10,7);
thread = new Thr(2000,textArea);
threadEvent = new Thr(1000,textArea2);
button = new JButton("Pausar/Reanudar");
this.getContentPane().add(button,BorderLayout.SOUTH);
this.getContentPane().add(textArea,BorderLayout.WEST);
this.getContentPane().add(textArea2,BorderLayout.EAST);
thread.start();
threadEvent.start();
button.addActionListener(this);
}
public void actionPerformed(ActionEvent event)
{
threadEvent.pushedButton();
}
}
public class MensajesHilos {
public static void main(String[] args){
Interface i = new Interface();
i.setTitle("Control Threads");
i.setBounds(200, 200, 300, 240);
i.setVisible(true);
}
}
The way you have coded, if you want to achieve the desired result,
I feel the modification need to be done in run method,
public void run()
{
while(true)
{
if(this.canPrint){
try
{
this.printCounter();
Thread.sleep(pause);
this.count++;
}
catch(InterruptedException e)
{
e.printStackTrace();
}
}
}
}
in this way, your Thread will never go dead and toggle printing based on canPrint boolean value.
Also, make sure to declare canPrint variable volatile, so that changes to it will be directly written to main memory and reflected immediately.
"button event doesn´t work properly"
This is false, if you put a print statement in the actionPerformed method, you will see that it is called every time you press the button.
By the way note that you can simplify this
if(canPrint)
this.canPrint = false;
else
this.canPrint = true;
To
this.canPrint = !this.canPrint;
Note that it is a good practice to always put #Override anotation on top of overriden method.
#Override
public void actionPerformed(ActionEvent event)
{
threadEvent.pushedButton();
}
Now why don't you get the expected result ?
You ommit to call thread.pushedButton, so the canPrint will only be reseted in the threadEvent object, and will never be in thread.
Note that once the boolean are set to false, you will exit the loop and the process won't start back after even if you re-set the boolean value to true. This example will works using while(true) however, you should change the true to any sentinel value to handle the exit of the program as this will loop forever.
#Override
public void run()
{
while(true)
{
if(this.canPrint)
{
this.printCounter();
this.count++;
}
try
{
Thread.sleep(pause);
}
catch(Exception e)
{
e.printStackTrace();
}
}
}
Also, make sure that pause is never 0 else you will eat all of the computer process.
Note that, as other stated, you should declare variables that are accessed in thread as volatile (canPrint) in your case.

How can I change JLabel text during work of JButton?

I would like my button 'licz' to: change text value of info to ''loading'', do something and change 'info' to "done". ('licz' is here a JButton, 'info' JLabel)
licz.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
info.setText("Loading..."); // Here
if(go())
{
brute(0);
info.setText("Done!"); //here
if(odwrot)
JOptionPane.showMessageDialog(frame, "good");
else
JOptionPane.showMessageDialog(frame, "bad");
}
else
{
JOptionPane.showMessageDialog(frame, "bad");
info.setText("Done"); // And here
}
}
});
But the program makes "something" first, changes 'info' label to "loading" and immediately to "done", how to keep these in case?
The event of actionPerformed is handled on the event handling thread, and should terminate fast to have a responsive GUI. Hence call invokeLater.
licz.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
info.setText("Loading...");
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
boolean good = false;
if (go())
{
brute(0);
good = odwrot;
}
JOptionPane.showMessageDialog(frame, good ? "good" : "bad");
info.setText("Done");
}
});
}
});
Or in java 8:
licz.addActionListener((e) -> {
info.setText("Loading...");
EventQueue.invokeLater(() -> {
boolean good = false;
if (go())
{
brute(0);
good = odwrot;
}
JOptionPane.showMessageDialog(frame, good ? "good" : "bad");
info.setText("Done");
});
});

Pass button click event to actionPerformed on key press

I'm working on a Java assignment that has to be done using AWT. I want a button to trigger by pushing the enter key while the button is in focus. I figured out how to do this in Swing with the doClick() method, but this doesn't seem to work in AWT. So far I'm trying this:
button.addActionListener(this); // Passes value from a TextBox to actionPerformed()
button.addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent e) {
if(e.getKeyCode()==KeyEvent.VK_ENTER) {
actionPerformed(null);
}
}
});
public void actionPerformed (ActionEvent e) {
try {
if (e.getSource() == button) {
// Stuff I want to happen
} else if (e.getSource() == anotherButton) {
// Other Stuff
} else { //third button
// More stuff
}
} catch (NumberFormatException nfe) {
// Null argument in keyPressed triggers this
// catches empty string exception from TextBox
}
}
As I mentioned with the comments, the null argument will trigger the catch. Does anyone have any idea what that argument might be for the button press or perhaps an altogether easier way to go about this? Thanks.
Edit - clarification: actionPerformed() does one of three things with input from a TextBox depending on which of three buttons is clicked. The try/catch is to catch empty string/format exceptions.
You can always have a method called something like onButtonPress(), which your actionPerformed can call, as well as your keyPressed.
button.addActionListener(this);
button.addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent e) {
if(e.getKeyCode() == KeyEvent.VK_ENTER) {
onButtonPress();
}
}
});
public void actionPerformed (ActionEvent e) {
if (e.getSource() == button){
onButtonPress();
}
}
private void onButtonPress(){
// do something
}

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