How to know java JRadio button is unselected - java

I have to make three radio buttons. On selection of the third radio button I have to show some text boxes. I also have to immediately remove the text boxes when the third radio button is unselected and any one of the other two is selected. I am looking for a callback when the JRadio button is unselected. I have supplied an ActionListener but it gets called only on selection and not on unselection. How do I achieve this toggle functionality with java JRadio button.
radioCustomButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
System.out.println("Callback called");
if(radioCustomButton.isSelected()){
System.out.println("Checked");
}
}
});
This is printing "Callback called" only on check but not on uncheck. I have added this radioCustomButton object in ButtonGroup as well.
I am left with the only option of supplying action listener to other two radio buttons and then write code to remove the text boxes.

Don't use an ActionListener to check when the button is selected.
Instead use an ItemListener and you will be notified when the button is selected and unselected.
See How to Write an Item Listener for an example.

Related

How to display Image when button1 is pressed

How can i display and image when button1 is pressed, this is the code im using to check for a button press:
public class clientFrameButtons {
public void frameClient(){........
....
button1.addActionListener(new ActionListener(){ //ActionListener checks for button press
public void actionPerformed(ActionEvent e){
// if button is pressed the following will happen
I've tried implementing an if statement and looked at several sources online but cannot find a answer to fit my needs.
Thanks.
ActionEvent is a logical event those intention is to signal the fact that a button was actioned. So it doesn't provide any information about the user inputs that have lead to the action (it may be a shortcut, a mouse press, your mouse could have been set to left-handed, etc). If you want to care about mouse, then you must catch mouse events, with an appropriate MouseListener.
So your problem can be expressed in two ways:
you want to display an image when a GUI button is actioned then use ActionListener.
you want to make different things depending on the mouse button pressed while over a GUI button, then use MouseListener.

How can I listen my all components with only one event?

Here is the problem,
I have 3 textfield, 3 button and 1 label. Their text are text1, text2 text3, but1,but2,but3.
I give you an example about what I want to do; When I double click on a button, button will change label's text as button's text. I mean when I double click to but2, label's text should be but2.
I can do this with that code;
MouseAdapter ml = new MouseAdapter() {
public void mouseClicked(MouseEvent me) {
if (me.getClickCount()==2) {
jLabel1.setText(jButton1.getText);
}
}
};
jButton1.addMouseListener(ml);
So It works but it works only for jButton1. I have to write different mouseListener's for all components(textfields and jbuttons). How can I do this with one listener? or one event ? Do you have any idea?
Take a look at MouseEvent#getSource ... although, to be honest, if you're using JButtons you shouldn't be using a MouseListener, but ActionListener instead. Also, generally speaking, most users won't double click a JButton as it's not intuitive for them to do so, buttons only need a single click to activate
Remember, buttons can be activated by the keyboard as well, which MouseListener won't be notified about

How can I enable/activate a radio button after a button is clicked?

Using a jFrame in Java and I have a set of radio buttons however I want these radio buttons to be activated once I have selected a certain button. What's the simplest way to do this? Thanks
Keep the radio buttons disabled initially.
Add an ActionListener to the button.
Implement actionPerformed() to enable the radio buttons.
Here is the Oracle tutorial.
Here is the TutorialsPoint tutorial.
This is small example to disable radio buttons.
JButton button = new JButton("Click");
JRadioButton one= new JRadioButton("one");
JRadioButton two= new JRadioButton("two");
JRadioButton three = new JRadioButton("three");
one.setEnabled(false);
two.setEnabled(false);
three.setEnabled(false);
//Group the radio buttons.
ButtonGroup group = new ButtonGroup();
group.add(one);
group.add(two);
group.add(three);
//Add action listener to button
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e)
{
// enable radion buttons.
one.setEnabled(true);
two.setEnabled(true);
three.setEnabled(true);
}
});
This is a demo idea how this thing working. This is just a basic demo. Button and radio buttons generated. And when click button you can enable them.
01. Generate button and three radio buttons to jframe.
02. Generate button-group and add those radio buttons.
03. In buttons action listener add that "enable radio button" code.
This link will be really helpful to you. Take a good look at that.
You tube link

Double if statement in java (swing, JFrame) not working

I'm trying to make a form so that when a user checks a checkbox and clicks a button, some code will execute. I've tried to do this in an if statement and nothing happens when I do the 2 things. I am doing this in Java with Swing.
Here is the code:
private class theHandler implements ActionListener{
public void actionPerformed(ActionEvent event){
String tftext;
tftext = tf1.getText();
if (event.getSource()==b1)
if(event.getSource()==cb1)
JOptionPane.showMessageDialog(null, tftext, "title", JOptionPane.INFORMATION_MESSAGE);
b1 is a button, cb1 is a checkbox and tf1 is a textfield.
Event.getSource() won't reference two different objects, it should reference the unique source of a single event, e.g. a Button in the case of a button click. Your nested statement will never execute.
It sounds like you should be handling the button click, and within that event handler check the state (checked or not) of the checkbox. If the checkbox is checked, then show your dialog.
Basically what you are saying there is that if the event came from the button and the event came from the checkbox, show a message.
This is not possible because one event cannot be triggered by a button and a checkbox in the same time. You cannot click on both in the same time.

How would I code when a item has been selected in a JList?

I have a JList with 5 options in it and when one of the items becomes selected or clicked i want the text area next to it to show a paragraph of text relative to the item clicked. It should do this for each item in the list but I cant seem to find how to do it in the API
How would my program know if an item in the JList was selected so I can work with the data?
Use addListSelectionListener. You can create a subclass (anonymous or not) of ListSelectionListener that does the work you want.
myList.addListSelectionListener(new ListSelectionListener()
{
public void valueChanged(ListSelectionEvent ev)
{
// handle ev
}
});
You should register a Listener for events on your JList. When the Swing UI fires one off, this Listener class will get the message and react accordingly.

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