Within two statements that have drastically shortened my code I need to add a statement that adds the text of a JButton to a StringBuilder. The ActionListener statement exists to disable the JButtons when clicked (a nice aesthetic), but I want to include if possible the ability to append the StringBuilder within the ActionListener as well. The following is the two parts of this code.
theModel.randomLetters();
ActionListener disableButton = new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
if (!(event.getSource() instanceof JButton)) {
return;
}
theModel.currentWord.append((JButton)event.getSource());
((JButton)event.getSource()).setEnabled(false);
}
};
for (int i = 0; i < 16; i++) {
JButton dice = new JButton(theModel.letters.get(i));
dice.addActionListener(disableButton);
boggleGrid.add(dice);
}
The .addActionListener(disableButton) adds the above ActionListener to each button when it is produced by the for loop. However,
theModel.currentWord.append((JButton)event.getSource());
is what I thought would properly append the StringBuilder "currentWord" with whatever value the clicked button holds (hence "((JButton)event.getSource())"). There are no errors per say but I have written separate lines of code in my main class to test whether there are any changes to the StringBuilder when any buttons are clicked. There isn't.
Where and what do I need to do to properly add the value of the clicked JButton to currentWord?
Using (JButton)event.getSource() will cause the StringBuilder to invoke the objects toString method. This isn't what you want, instead, either use the JButton's text property or the ActionEvent's actionCommand property, for example...
theModel.currentWord.append(((JButton)event.getSource()).getText());
or
theModel.currentWord.append(event.getActionCommand());
instead
Unless you specify the JButton's actionCommand yourself, it will use the buttons text as the actionCommand
Related
I have a group of loop generated buttons made with this code
this.panelCuerpo.setLayout(new GridLayout(4,5));
for(int i = 1; i<=20; i++){
final JToggleButton b = new JToggleButton(new ImageIcon("/images/available.png"));
panelCuerpo.add(b);
b.setIcon(new javax.swing.ImageIcon(getClass().getResource("/Images/available1.png")));
b.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent evt){
if(b.isSelected()){
b.setIcon(new javax.swing.ImageIcon(getClass().getResource("/Images/busy1.png")));
cantidadBoletas++;
}else{
b.setIcon(new javax.swing.ImageIcon(getClass().getResource("/Images/available1.png")));
cantidadBoletas--;
}
System.out.println(cantidadBoletas);
}
});
}
The problem here is that I can't use setText() to compare later cause there's no property to hide that text. How can I compare it later?
PS. Each button has a consecutive number, it's easy to assign that number. The real problem lies in where to put it.
You could:
Use the Action API, which lets you trigger the selected state of the associated button. This allows you to de-couple the button from the underlying "action" it should take. Take a look at How to Use ActionsHow to Use Actions for more details
Use the actionCommand property of the JButton. This allows you to have some kind of "identifier" associated with the button which is independent of the text
Use an array or List to maintain a reference to the buttons
You can maintain a List<JToggleButton> of JToggleButton and fetch element later by the index. Apart from that instead of adding ActionListener in loop you can implement ActionListener which can be used for all buttons and you just need to write b.addActionListener(this); in loop.
NOTE : better to start from i = 0 instead of 1
I have added set of integers to a JTextArea for each button click.
what exactly I want is that I want to add all the integers and display in a separate JTextArea,Also I want to ask whether we can access the value of a variable within an action listener outside the action listener.
Here is the code:
private ActionListener listener = new ActionListener() {
#Override
public void actionPerformed(ActionEvent evt) {
if(evt.getActionCommand().equals(t.getText()))
{
onec=one.calone(n);
td.append(Double.toString(onec));
td.append("\n");
}
res=Integer.parseInt(td.getText());
}
};
When the user presses button 't' It will keep on adding the integer 'onec' to
textarea 'td' using append method.And I have stored the result from the action
listener into a variable 'res' of double datatype.
private ActionListener listener2 = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if(e.getActionCommand().equals(tot.getText()))
{
totd.setText(Double.toString(res));
}
}
};
When the user clicks the button 'tot',It should add all the integers in the
textarea 'td' and display it in the textarea 'totd'.
This code is not working.
Please help me this is the last part of my project.
As I don't know what is not working - it would of been good if you explained more clearly - my guess is...
Instead of Double.toString(onec)
Use String.valueOf(onec)
EDIT: If this is not the case, please elaborate on what your problem is, and a fuller code listing.
converting the contents of the textArea to double does not calculate sum. Try looping throught the first textArea reading each value while calculating the sum
I have an array I fill with buttons and I want an individual button to change its text when clicked.
for (int i = 0; i<4; i++)
{
button[i] = new JButton ("Add");
button[i].addActionListener(this);
box[i] = new JComboBox();
foodOptions.add(box[i]);
foodOptions.add(button[i]);
}
public void actionPerformed (ActionEvent e)
{
button[this].setText("I've been clicked!");
}
The current doesn't work because of incompatible types, what format is appropriate?
Yes, it makes no sense to pass an object, this, into an array index which expects an int, not your GUI object, so I'm not sure what you were trying to achieve with this.
Just get a reference to the JButton that's been clicked from the ActionEvent's getSource() method:
JButton btn = (JButton)e.getSource();
btn.setText("I've been clicked");
Edit:
Also you should avoid using this as your ActionListener since this means that you're likely having your GUI class implement an ActionListener which is asking the poor class to be too many things, to do too much. You're much better off either using anonymous inner classes or else even better use AbstractActions.
I am writing a program that contains a JButton. Every time the button is clicked, a new JTextField is added to a JPanel.
My problem is that, after the user has created all the JTextFields and filled them with information, I need to get the text of each field. How can I get access to the JTextFields when they are dynamically generated, as they don't have instance names? Is there a better way to get the text of each one, without knowing their instance name.
Here is the code of the actionPerformed event of the JButton...
private void jButton4ActionPerformed(java.awt.event.ActionEvent evt) {
JTextField x = new JTextField();
x.setColumns(12);
p.add(x);
validate();
}
You say you want to get the text from each field. So, when you create the new instances x, why don't you keep a collection of them, such as adding the JTextFields to an ArrayList?
Alternatively, assuming that p is a JPanel, you should be able to get all the children, which would be the JTextFields that you're adding. Try using getComponents() like so...
Component[] children = p.getComponents();
for (int i=0;i<children.length;i++){
if (children[i] instanceof JTextField){
String text = ((JTextField)children[i]).getText():
}
}
You can find them all by looping through the components of the panel (or whatever "p" is). If necessary, check if each is a text box. That is, do p.getComponents and then loop through the returned array. Like:
Component[] components=p.getComponents();
for (Component c : components)
{
if (c instanceof JTextField)
{
String value=((JTextField)c).getText();
... do whatever ...
}
}
If they are interchangeable, that should be all you need. If you need to distinguish them, I think the cleanest thing to do would be to create your own class that extends JTextField and that has a field for a name or sequence number or whatever you need.
HI all,
I'm trying to write a simple star rating component. I'm fairly new to the Java language and I'm not sure if what i want to accomplish can even be done in Java. Is it possible for me to add a JLabel inside an array of JLabel, and each JLabel in the array will have a mouse event listener. Now is it possible to set it up so that when the mouse event fires on say Label[3] that i can get the index value of it?
Here is how I built my Panel
public Rating(Integer max,int size) {
JLabel position = new JLabel[max];
this.setLayout(new FlowLayout());
for(int i=0; i != max;i++){
position[i]=new JLabel(icons.getIcon("star-empty", size));
position[i].setOpaque(true);
position[i].addMouseListener(this);
add(position[i]);
}
}
#Override
public void mouseEntered(MouseEvent e) {
JLabel a= (JLabel) e.getComponent();
//****Have some code in here to tell me where in the position array the event came from????***
int index = ?????
}
Thoughts/Idea/Suggestions please.
Note I thought of using buttons, but it looks messy and would love to find a way with ImageIcons.
THanks.
Instead of using the same listener for each label like you did:
position[i].addMouseListener(this);
...you can create a special listener class that takes the index number, and allows you to find it later:
position[i].addMouseListener(new RatingMouseListener(i));
Each label will have a separate instance of the listener with a different index value. The code for the inner class would look like something like this:
private class RatingMouseListener extends MouseAdapter {
private final int index;
public RatingMouseListener(int index) {
this.index = index;
}
#Override
public void mouseEntered(MouseEvent e) {
System.out.println("Mouse entered for rating " + index);
}
#Override
public void mouseExited(MouseEvent e) {
System.out.println("Mouse exited for rating " + index);
}
}
Then, you just override any method in MouseAdapter.
Also, like other people said, you might want to use JButtons instead of JLabels because they have better support for action events. You can still give them icons.
You could name each JLabel according to its index using its setName method, then use the MouseEvent's getComponent method to get the originating JLabel back, use getName on it and there's your index. That would be one way, but would involve storing the index information in two places (implicitly in its placement in the array, and explicitly as the label's name), so it's pretty much begging for inconsistency to arise.
You could also search through the array for the JLabel reference you get from getComponent, but that's not so great either, especially for large arrays.
The way I usually do it is:
int i;
for (i = 0; i <max; i++)
if (position[i] == e.getcomponent())
break;
now position[i] is the label you are looking for.
Just know that JButtons can look any way you'd like. They can have ImageIcons and don't even have to look like buttons.
Why is the index important? You know how to get the component, so just loop through the array to get the index.
Note I thought of using buttons, but it looks messy and would love to find a way with ImageIcons.
How does using a button solve the problem of determining the index? However, I also agree using a button is better than a label and then you would use an ActionListener instead of a MouseListener. You can make the button look like a label by using:
button.setBorderPainted( false );
Now if you use an ActionListener you can use the setActionCommand(...) method to store the index value of the button. Then in the event you use the getActionCommand(...) method.