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javaswingbuttonidentification

How to get specific ID for a JButton?


I'm trying to build a program that utilizes a 3x3 grid of buttons (using Java Swing), so I initialize it with a GridLayout and a loop to create the buttons:

     panel.setBorder(BorderFactory.createEmptyBorder(3,3,5,5))
     panel.setLayout(new GridLayout(3,3,10,10));

    String[] buttons = {"Top Left", "Top Middle", "Top Right", "Middle Left", "Middle", "Middle Right", "Bottom Left", "Bottom Middle", "Bottom Right"};

    for(int i = 0; i < buttons.length; i++) {
        buttray[i] = new JButton(buttons[i]);
        panel.add(buttray[i]);
        buttray[i].addActionListener(this);
    }

The buttons load just fine, but I do not understand how to use ActionListeners to differentiate between the buttons. When I check the paramString() method from the printout, each button gives the same modifier:

Top Left
ACTION_PERFORMED,cmd=Top Left,when=1431640106712,modifiers=Button1
Top Middle
ACTION_PERFORMED,cmd=Top Middle,when=1431640107566,modifiers=Button1
Top Right
ACTION_PERFORMED,cmd=Top Right,when=1431640107978,modifiers=Button1

Does this modifier value act as the button's identifier, and if so, how do I change it?


Solution

  • There are multiple ways to distinguish which button fired the ActionEvent:

    1. Set/get the action command of each button (eg if (e.getActionCommand().equals("Top Left"))
    2. Use == to compare instances (eg if (e.getSource() == buttray[0] ))
    3. Get the text of the JButton (eg if (e.getSource().getText().equals("Top Left"))
    4. Set/get the name of the JButton (eg if (e.getSource().getName().equals("Top Left"))
    5. Add a different ActionListener to each button (in other words 1:1 Listener to button)
    6. ...and perhaps more ways will be added in the comments section below.