使用JButton ActionListener在同一个包中运行不同的类

Question

I'm having an issue as I'm relatively new to GUI .

Basically to put everyone in the picture, I have a package which consists of:

• my MainClass (Includes the GUI)
• A seperate Class (Don't want it to run unless button is clicked)
• Another seperate class which I don't want to run unless it's specific button is clicked.

So my MainClass GUI is basically the controller.

However, I honestly have no clue how to go about it. Was told to have to create a constructor and use getters/setters? However I still don't understand how to call that specific class whilst leaving the other off "Turned off" .

Thanks.

Answer 1

Well, there are quite a few ways to do this... Either you create anonymous listeners for each button, and then, depending on what you want to do, trigger methods in other classes or the like;

JButton b1 = new JButton();
b1.addActionListener(new ActionListener(){

    public void actionPerformed(ActionEvent e)
    {
        //Do something!
        OtherClass other = new OtherClass();
        other.myMethod();
    }
});

JButton b2 = new JButton();
b2.addActionListener(new ActionListener(){

    public void actionPerformed(ActionEvent e)
    {
        //Do something else!
        ...
    }
});

Alternatively, you use the command string and associate a unique command (made final, preferably) which you compare with when receiving a actionPerformed in a common listener implementation;

//In your class, somewhere...
public final static String CMD_PRESSED_B1 = "CMD_PRESSED_B1";
public final static String CMD_PRESSED_B2 = "CMD_PRESSED_B2";

//Create buttons
JButton b1 = new JButton();
JButton b2 = new JButton();

//Assign listeners, in this case "this", but it could be any instance implementing ActionListener, since the CMDs above are declared public static
b1.addActionListener(this);
b2.addActionListener(this);

//Assign the unique commands...
b1.setActionCommand(CMD_PRESSED_B1);
b2.setActionCommand(CMD_PRESSED_B2);

And then, in your listener implementation;

public void actionPerformed(ActionEvent e)
{
    if (e.getActionCommand().equals(CMD_PRESSED_B1)
    {
        //Do something!
        OtherClass other = new OtherClass();
        other.myMethod();
    }

    else if (e.getActionCommand().equals(CMD_PRESSED_B2)
    {
        //Do something else!
        ...
    }
}