Is there a way to know if a JButton was clicked consecutively? Consider my code.
public void actionPerformed(ActionEvent arg0) {
String bucky[] = new String[2];
String firstclick = null, secondclick = null;
clicks++;
if (clicks == 1) {
bucky[0] = firstclick;
} else if(clicks == 2) {
bucky[1] = secondclick;
if (bucky[0] == bucky[1]) {
//This JButton was clicked twice in a row.
}
}
This code checks the entire number of times my JButton was clicked and displays the message "This button was clicked twice in a row". What I want is to compare two clicks from that button and see if they come one after the other rather than counting the number of clicks made. Or is there a built-in function that does this?
Just use a field remembering what the last clicked button was:
private JButton lastButtonClicked;
...
someButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (lastButtonClicked == e.getSource()) {
displayError();
}
else {
lastButtonClicked = (JButton) e.getSource();
doSomething();
}
}
});
Of course, you'll have to do the same thing with all the other buttons.
I have a different approach to your problem:
You want to not allow the user to press the same button in some group of buttons twice in a row.
You're solutions so far have tried to check which button was pressed last, and then warn the user if the same button has been pressed in a row.
Perhaps a better solution is to create a construct that simply doesn't allow the user to press the same button twice in a row.
You can create your ButtonGroup like object that selectively disables the last button pressed, and enables all the other buttons.
You would give this class an add(AbstractButton btn) method to allow you to add all the buttons that you wish to behave this way to it. The button would then be added to an ArrayList.
You would give it a single ActionListener that listens to all the buttons. Whenever the actionPerformed method has been pressed, it enables all of the buttons, and then selectively disables the last button pressed.
For instance consider my class below:
public class NoRepeatButtonGroup implements ActionListener {
private List<AbstractButton> btnList = new ArrayList<>();
public void add(AbstractButton btn) {
btnList.add(btn);
btn.addActionListener(this);
}
#Override
public void actionPerformed(ActionEvent evt) {
for (AbstractButton btn : btnList) {
btn.setEnabled(true);
}
((AbstractButton) evt.getSource()).setEnabled(false);
}
public void reset() {
for (AbstractButton btn : btnList) {
btn.setEnabled(true);
}
}
}
If you create a single object of this in your class that creates the buttons, and add each button to the object of this class, your code will automatically disable the last button pressed, and re-enable it once another button has been pressed.
You could use it like so:
JPanel buttonPanel = new JPanel(new GridLayout(1, 0, 5, 0));
NoRepeatButtonGroup noRepeatButtonGroup = new NoRepeatButtonGroup();
JButton yesButton = new JButton(new YesAction());
noRepeatButtonGroup.add(yesButton);
buttonPanel.add(yesButton);
JButton noButton = new JButton(new NoAction());
noRepeatButtonGroup.add(noButton);
buttonPanel.add(noButton);
JButton maybeButton = new JButton(new MaybeAction());
noRepeatButtonGroup.add(maybeButton);
buttonPanel.add(maybeButton);
For example, here is a proof of concept minimal runnable example:
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import javax.swing.*;
public class NoneInARowBtns {
private static void createAndShowGui() {
JPanel buttonPanel = new JPanel(new GridLayout(1, 0, 5, 0));
NoRepeatButtonGroup noRepeatButtonGroup = new NoRepeatButtonGroup();
int buttonCount = 5;
for (int i = 0; i < buttonCount; i++) {
JButton btn = new JButton(new ButtonAction(i + 1));
noRepeatButtonGroup.add(btn);
buttonPanel.add(btn);
}
JOptionPane.showMessageDialog(null, buttonPanel);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
#SuppressWarnings("serial")
class ButtonAction extends AbstractAction {
public ButtonAction(int i) {
super("Button " + i);
}
#Override
public void actionPerformed(ActionEvent e) {
System.out.println(e.getActionCommand() + " Pressed");
}
}
class NoRepeatButtonGroup implements ActionListener {
private List<AbstractButton> btnList = new ArrayList<>();
public void add(AbstractButton btn) {
btnList.add(btn);
btn.addActionListener(this);
}
#Override
public void actionPerformed(ActionEvent evt) {
for (AbstractButton btn : btnList) {
btn.setEnabled(true);
}
((AbstractButton) evt.getSource()).setEnabled(false);
}
public void reset() {
for (AbstractButton btn : btnList) {
btn.setEnabled(true);
}
}
}
When the above program runs, and when the second button is pressed, you will see that it is disabled:
Then when the 3rd button has been pressed, the 2nd is re-enabled, and the 3rd one is disabled:
And etc for the 4th button....
A global variable arrau of booleans, one for each button, set true on first click, set false or second, sjould do it
Related
I'm getting stuck while building a forum like application which has a vote button.
I have vote up and vote down button for each content which are automatically generated. I want this button to only display the up and down arrow but not any text or label.. how can i find out which button is pressed?
Automated content..
ImageIcon upvote = new ImageIcon(getClass().getResource("vote_up.png"));
ImageIcon downvote = new ImageIcon(getClass().getResource("vote_down.png"));
JButton vote_up = new JButton(upvote);
JButton vote_down = new JButton(downvote);
vote_up.addActionListener(voting);
vote_down.addActionListener(voting);
Action voting = new AbstractAction(){
#Override
public void actionPerformed(ActionEvent e){
//What to do here to find out which button is pressed?
}
};
any help is appreciated.
public void a(){
int crt_cnt = 0;
for(ClassA temp : listofClassA)
{
b(crt_cnt);
crt_cnt++;
}
}
public void b(crt_cnt){
//draw button
}
As from above, I have multiple vote_up and vote_down button created by the b function, how can i differentiate which crt_cnt is the button from?
There are multiple ways you might achieve this
You could...
Simply use the source of the ActionEvent
Action voting = new AbstractAction(){
#Override
public void actionPerformed(ActionEvent e){
if (e.getSource() == vote_up) {
//...
} else if (...) {
//...
}
}
};
This might be okay if you have a reference to the original buttons
You could...
Assign a actionCommand to each button
JButton vote_up = new JButton(upvote);
vote_up.setActionCommand("vote.up");
JButton vote_down = new JButton(downvote);
vote_down .setActionCommand("vote.down");
//...
Action voting = new AbstractAction(){
#Override
public void actionPerformed(ActionEvent e){
if ("vote.up".equals(e.getActionCommand())) {
//...
} else if (...) {
//...
}
}
};
You could...
Take full advantage of the Action API and make indiviual, self contained actions for each button...
public class VoteUpAction extends AbstractAction {
public VoteUpAction() {
putValue(SMALL_ICON, new ImageIcon(getClass().getResource("vote_up.png")));
}
#Override
public void actionPerformed(ActionEvent e) {
// Specific action for up vote
}
}
Then you could simply use
JButton vote_up = new JButton(new VoteUpAction());
//...
Which will configure the button according to the properties of the Action and will trigger it's actionPerformed method when the button is triggered. This way, you know 100% what you should/need to do when the actionPerformed method is called, without any doubts.
Have a closer look at How to Use Actions for more details
You can detect by using the method getSource() of your EventAction
Action voting = new AbstractAction(){
#Override
public void actionPerformed(ActionEvent e){
if (e.getSource() == vote_up ) {
// vote up clicked
} else if (e.getSource() == vote_down){
// vote down clicked
}
}
};
hey thanks for all the help and assistance! I've finally got it! I solved it by
assigning a text on the button, +/- for vote up or down, followed by the content id which i required, then change the font size to 0
vote.setText("+"+thistopic.content.get(crt_cnt).get_id());
vote.setFont(heading.getFont().deriveFont(0.0f));
after that i could easily trace which button is pressed by comparing to the
actionEvent.getActionCommand()
which return the text on the button!
I would wrap the JButton similar to this:
JButton createMyButton(final JPanel panel, final String text,
final boolean upOrDown, final int gridx, final int gridy) {
final JButton button = new JButton();
button.setPreferredSize(new Dimension(80, 50));
final GridBagConstraints gbc = Factories.createGridBagConstraints(gridx,
gridy);
panel.add(button, gbc);
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(final ActionEvent e) {
myActionPerformed(text, upOrDown);
}
});
return button;
}
You could use an int instead of the text, if more convenient.
I am programming my first complex application in Java, Swing. When I have added ActionListener to my JButton.
ActionListener changeButton = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e){
if(startButton.getText() == "Spustit") {
startButton.setText("STOP");
} else {
startButton.setText("Spustit");
}
}
}
I am adding ActionListener to the button itself
private void startButtonActionPerformed(java.awt.event.ActionEvent evt) {
startButton.addActionListener(changeButton);
}
Can you tell me where I coded ActionListener badly?
Thanks to all!
You have coded the ActionListener good enough to be working, at least, for the action listener itself. The problem is that you are adding the action listener after an event (your second sample), thus your action listener will get called the second time you will click it.
A solution is very simple:
JButton button = new JButton();
button.addActionListener( new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
//...
}
});
Now the action listener should activate on the first click if you directly add a new ActionListener to the button, not after an action is performed
Why are you adding the actionlistener in actionPerformed? I think you should do something like this:
public static void main(String[] args) {
final JButton startButton = new JButton("Spustit");
ActionListener changeButton = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if (startButton.getText() == "Spustit") {
startButton.setText("STOP");
} else {
startButton.setText("Spustit");
}
}
};
startButton.addActionListener(changeButton);
// Add it to your panel where you want int
}
Is there a way I can disable mouse click ? In the panel there are different components and for some of the Button Click events, I want to disable the mouse click. I mean the click of the mouse doesn't have any effect on the components. I can disable using the setEnabled() function but I don't want to do that way.
Is there any way I can disable the mouse click ?
Situation :
private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {
//..disable the mouse click on each component present inside the panel
}
You can add an extended ActionListener to all the buttons like this:
public abstract class ExtendedActionListener implements ActionListener{
private static boolean disabled = false;
public static void setDisabled(boolean disabled){
ExtendedActionListener.disabled = disabled;
}
#Override
public final void actionPerformed(ActionEvent e){
if(disabled)
return;
doSomething;
}
}
And now just disable all the ActionListeners by calling the method setDisabled(false). The Button visual behavior doesn't change at all, but nothing happens, when you click on it.
If the visual click behaviour doesn't matter, then you can just remove the MouseListeners.
You can create a button group like this:
public class SingleSelectionButtonGroup {
private final List<JButton> buttons;
public static SingleSelectionButtonGroup group(List<JButton> buttons) {
return new SingleSelectionButtonGroup(buttons);
}
public static SingleSelectionButtonGroup group(JButton...buttons) {
return new SingleSelectionButtonGroup(Arrays.asList(buttons));
}
private SingleSelectionButtonGroup(List<JButton> buttons) {
this.buttons = new ArrayList<JButton>(buttons);
setupListener();
}
private void setupListener() {
ActionListener listener = new ActionListener() {
public void actionPerformed(ActionEvent e) {
SingleSelectionButtonGroup.this.disableAllExcept((JButton) e.getSource());
}
};
for (JButton button : buttons) {
button.addActionListener(listener);
}
}
private void disableAllExcept(JButton clickedButton) {
for (JButton button : buttons) {
if (!clickedButton.equals(button)) {
button.setEnabled(false);
}
}
}
}
And then uses it with a collection of buttons that you want to group:
public class Application {
public void run() {
final JFrame frame = new JFrame("test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(new Dimension(400, 300));
final JPanel pane = new JPanel();
List<JButton> buttons = new ArrayList<JButton>();
String[] texts = {"A", "B", "C"};
for (String text : texts) {
JButton button = new JButton(text);
buttons.add(button);
pane.add(button);
}
SingleSelectionButtonGroup.group(buttons);
frame.getContentPane().add(pane);
frame.setVisible(true);
}
public static void main(String[] args) {
new Application().run();
}
}
you should use one common class of your listener and have static method for turn listener turn on and off
public abstract class BaseMouseListener implements ActionListener{
private static boolean active = true;
public static void setActive(boolean active){
BaseMouseListener.active = active;
}
protected abstract void doPerformAction(ActionEvent e);
#Override
public final void actionPerformed(ActionEvent e){
if(active){
doPerformAction(e);
}
}
}
your listeners would have to implements doPerformedAction()
Add empty mouse listener. This will "disable" the click because it will not have any effect.
Okay so I am making a 2d array of JToggleButtons. I got the action listener up and going, but I have no way to tell which button is which.
If I click one, all it returns is something like
javax.swing.JToggleButton[,59,58,19x14,alignmentX=0.0,alignmentY=0.5,border=javax.swing.plaf.BorderUIResource$CompoundBorderUIResource#53343ed0,flags=296,maximumSize=,minimumSize=,preferredSize=,defaultIcon=,disabledIcon=,disabledSelectedIcon=,margin=javax.swing.plaf.InsetsUIResource[top=2,left=14,bottom=2,right=14],paintBorder=true,paintFocus=true,pressedIcon=,rolloverEnabled=false,rolloverIcon=,rolloverSelectedIcon=,selectedIcon=,text=]
Is there anyway to stick some sort of item or number in the button object to associate each button?
And then when the button is clicked I can retrieve that item or number that was given to it?
Here is my button generator code. (How could I make "int l" associate (and count) to each button made, when it is called, it will return that number, or something along those lines.
JToggleButton buttons[][] = new JToggleButton[row][col];
int l = 0;
for (int i = 0; i < row; i++) {
for (int j = 0; j < col; j++) {
buttons[i][j] = new JToggleButton("");
buttons[i][j].setSize(15,15);
buttons[i][j].addActionListener(new e());
panel.add(buttons[i][j]);
l++;
}
}
ActionListner
public class e implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
Object source = e.getSource();
System.out.println(source);
}
}
variable "source" is what I use to get my data, so how can int l, be returned through "source" (as its unique value for the unique button clicked) as a button is clicked?
Thanks,
-Austin
very simple way is add ClientProperty to the JComponent, add to your definition into loop e.g.
buttons[i][j].putClientProperty("column", i);
buttons[i][j].putClientProperty("row", j);
buttons[i][j].addActionListener(new MyActionListener());
rename e to the MyActionListener and change its contents
public class MyActionListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
JToggleButton btn = (JToggleButton) e.getSource();
System.out.println("clicked column " + btn.getClientProperty("column")
+ ", row " + btn.getClientProperty("row"));
}
EDIT:
for MinerCraft clone isn't required to implements ony of Listeners, there is only about Icon, find out that in this code (don't implement any of Listeners anf remove used ItemListener)
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ButtonsIcon extends JFrame {
private static final long serialVersionUID = 1L;
private Icon errorIcon = UIManager.getIcon("OptionPane.errorIcon");
private Icon infoIcon = UIManager.getIcon("OptionPane.informationIcon");
private Icon warnIcon = UIManager.getIcon("OptionPane.warningIcon");
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
ButtonsIcon t = new ButtonsIcon();
}
});
}
public ButtonsIcon() {
setLayout(new GridLayout(2, 2, 4, 4));
JButton button = new JButton();
button.setBorderPainted(false);
button.setBorder(null);
button.setFocusable(false);
button.setMargin(new Insets(0, 0, 0, 0));
button.setContentAreaFilled(false);
button.setIcon((errorIcon));
button.setRolloverIcon((infoIcon));
button.setPressedIcon(warnIcon);
button.setDisabledIcon(warnIcon);
add(button);
JButton button1 = new JButton();
button1.setBorderPainted(false);
button1.setBorder(null);
button1.setFocusable(false);
button1.setMargin(new Insets(0, 0, 0, 0));
button1.setContentAreaFilled(false);
button1.setIcon((errorIcon));
button1.setRolloverIcon((infoIcon));
button1.setPressedIcon(warnIcon);
button1.setDisabledIcon(warnIcon);
add(button1);
button1.setEnabled(false);
final JToggleButton toggleButton = new JToggleButton();
toggleButton.setIcon((errorIcon));
toggleButton.setRolloverIcon((infoIcon));
toggleButton.setPressedIcon(warnIcon);
toggleButton.setDisabledIcon(warnIcon);
toggleButton.addItemListener(new ItemListener() {
#Override
public void itemStateChanged(ItemEvent e) {
if (toggleButton.isSelected()) {
} else {
}
}
});
add(toggleButton);
final JToggleButton toggleButton1 = new JToggleButton();
toggleButton1.setIcon((errorIcon));
toggleButton1.setRolloverIcon((infoIcon));
toggleButton1.setPressedIcon(warnIcon);
toggleButton1.setDisabledIcon(warnIcon);
toggleButton1.addItemListener(new ItemListener() {
#Override
public void itemStateChanged(ItemEvent e) {
if (toggleButton1.isSelected()) {
} else {
}
}
});
add(toggleButton1);
toggleButton1.setEnabled(false);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
pack();
setVisible(true);
}
}
Just add the row and column data to each listener. You could add an explicit constructor, but I suggest adding a little method (which may have more added to it later).
buttons[i][j].addActionListener(e(i, j));
...
private ActionListener e(final int i, final int j) {
return new ActionListener() {
// i and j available here
...
(In JDK8 you should be able to use a lambda to reduce the syntax clutter.)
And then renaming it with a better name.
I made a minesweeper game and ran into a similar problem. One of the only ways you can do it, is to get the absolute location of the clicked button, then divide that by the x and y between buttons, so for me it was
if ((e.getComponent().getX() != (randx) * 25 && e.getComponent().getY() != (randy) * 25) &&bomb[randx][randy] == false) {
This code was to check if the area had bombs. So I had 25 x and y difference between location of bombs. That will just give you a general idea on how to do this.
I believe: (x - x spacing on left side) / buffer - 1 would work.
Instead of 'e.getSource()' you can always call 'e.getActionCommand()'. For each button you can specify this by:
JButton button = new JButton("Specify your parameters here"); /*you get these from getActionCommand*/
button.setText("title here"); /*as far as I remember*/
My program has one button, and the other one is a JTextField. The action listener for the button and the textfield are different. I'm using:
textfield.addActionListener(this);
button.addActionListener(this);
... inside my constructor.
They both do the same actionListener. How can I call their respective methods?
You are implementing ActionListener in the class of both components. So, when an action happens, actionPerformed method of the class is called for both of them. You can do following to separate them:
1-Create a separate class and implement ActionListener interface in it and add it as a actionListener for one of the components.
2-In actionPerformed method, there is a parameter with ActionEvent type. Call getSource method of it and check if it returns the object of JTextField or JButton by putting an if statement and do separate things accordingly.
Obviously both components share an ActionListener. If you want to determine which component generated the ActionEvent, invoke getSource(). And from there, you can typecast (if needed), and then invoke that particular component's methods.
For me the easiest way to do what is asked is the following:
textfield.addActionListener(this);
button.addActionListener(this);
...
public void actionPerformed(ActionEvent e){
if( e.getSource().getClass().equals(JTextField.class) ){
System.out.println("textfield");
//Código para el textfield
}
if( e.getSource().getClass().equals(JButton.class) ){
System.out.println("JButton");
//Código para el JButton
}
}
When an action listener is activated, because someone click your button, the method actionPerformed is called. As you havae set this as an action listener, you should have a method actionPerformed in your class. This is the method called in both cases.
Something like:
class MyClass implements ActionListener {
public MyClass() {
...
textfield.addActionListener(this) ;
button.addActionListener(this) ;
...
}
public void actionPerformed(ActionEvent e) {
// This is the method being called when:
// - the button is clicked and
// - the textfield activated
}
}
Though if you have not given your sample code, but I can understand what is there.
Here is an example of how to add listener to any JComponent. (Dont try to run this code!!!)
import java.awt.Button;
import java.awt.TextArea;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
public class EventListeners extends JFrame implements ActionListener {
TextArea txtArea;
String Add, Subtract, Multiply, Divide;
int i = 10, j = 20, sum = 0, Sub = 0, Mul = 0, Div = 0;
public void init() {
txtArea = new TextArea(10, 20);
txtArea.setEditable(false);
add(txtArea, "center");
Button b = new Button("Add");
Button c = new Button("Subtract");
Button d = new Button("Multiply");
Button e = new Button("Divide");
// YOU ARE DOING SOMETHING LIKE THIS
// THIS WILL WORK, BUT CAN BE A BAD EXMPLE
b.addActionListener(this);
c.addActionListener(this);
d.addActionListener(this);
e.addActionListener(this);
add(b);
add(c);
add(d);
add(e);
}
public void actionPerformed(ActionEvent e) {
sum = i + j;
txtArea.setText("");
txtArea.append("i = " + i + "\t" + "j = " + j + "\n");
Button source = (Button) e.getSource();
// you can work with them like shown below
Button source = (Button) e.getSource();
if (source.getLabel() == "Add") {
txtArea.append("Sum : " + sum + "\n");
}
if (source.getLabel() == "Subtract") {
txtArea.append("Sub : " + Sub + "\n");
}
if (source.getLabel() == "Multiply") {
txtArea.append("Mul = " + Mul + "\n");
}
if (source.getLabel() == "Divide") {
txtArea.append("Divide = " + Div);
}
}
}
UPDATE
You should do something like below
Button b = new Button("Add");
Button c = new Button("Subtract");
b.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
// implement what is expected for b button
}
});
c.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
// implement what is expected for c button
}
});
// and so on...
// but yes we can improve it
Just set different ActionCommands on each component.
In the actionPerformed method you can check the ActionCommand of the event:
private static final String TEXT_CMD = "text"; // or something more meaningful
private static final String BUTTON_CMD = "button";
...
textfield.setActionCommand(TEXT_CMD);
textfield.addActionListener(this);
button.setActionCommand(BUTTON_CMD);
button.addActionListener(this);
...
public void actionPerformed(ActionEvent ev) {
switch (ev.getActionCommand()) {
case TEXT_CMD:
// do textfield stuff here
break;
case BUTTON_CMD:
// do button stuff here
break;
default:
// error message?
break;
}
}