How do i know if a Jcheckbox is checked?in GUI [closed]

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Closed 6 years ago.

can you tell me in details how do i know if a jcheckbox is checked or not? method isSelected didn't work with me it gives me an exception while running

{
 Sandwich = new JButton("Tall");
         contentPane.add(Tall);
         Sandwitch.setBounds(350, 110, 90,40);   //in main
         Sandwitch.addActionListener(this);

}
.....

public void actionPerformed(ActionEvent event) {
JButton clickedButton = (JButton) event.getSource();

        String  buttonText = clickedButton.getText();
..........
if(clickedButton.getText()=="Sandwitch"){
        if(Ketchup.getState()&&!Garlic.getState()){//

       itm=new Item(""+m+clickedButton.getText(),3.0);
        xyz.addItem(itm);
       textArea.append(" "+clickedButton.getText()+",");
        textArea.append(" "+itm.getPrice()+"\n");}

          else if(!Ketchup.isSelected()&&Garlic.isSelected()){//

....................
}

it gives a very long exception while running

can you please help me with this problem?

回答1:

Don't use == to compare Strings!

if (clickedButton.getText()=="Sandwitch"){}

Use equals or equalsIgnoreCase()

if ("Sandwich".equalsIgnoreCase(clickedButton.getText()){
    // do something
}

来源：https://stackoverflow.com/questions/20286460/how-do-i-know-if-a-jcheckbox-is-checkedin-gui