如何向JPanel添加方法？

Question

I working on this assignment and I have a problem where I need to add this matrix to a JPanel. I made the matrix in another method because I thought it would be easier but can't find a solution. I also used this layout by following a tutorial on Oracles website if it look familiar.

The text also needs to be editable which is why I have buttons. I don't have there functions here either.

public static void addComponentsToPane(Container pane) {

    if (RIGHT_TO_LEFT) {
        pane.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);
    }

    JPanel array;
    JButton button;
    pane.setLayout(new GridBagLayout());
    GridBagConstraints c = new GridBagConstraints();

    if (shouldFill) {
        c.fill = GridBagConstraints.HORIZONTAL;
    }

    button = new JButton("Reset to 0");
    pane.add(button, c);

    // WHERE IT NEEDS TO BE ADDED***********************
    array = new JPanel();
    pane.add(array, c);

}

private static void createAndShowGUI() {
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    addComponentsToPane(frame.getContentPane());
    frame.pack();
    frame.setVisible(true);
}

public int[][] getRandomMatrix() {
int[][] randomMatrix = new int[10][10];
    for (int r = 0; r < randomMatrix.length; r++) {
        for (int c = 0; c < randomMatrix[r].length; c++) {
        randomMatrix[r][c] = (int)(Math.random() * 2);
        }
    }
    return randomMatrix;
}

public static void main(String[] args) {
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            createAndShowGUI();
        }
    });
}

Answer 1

From the question you outline, it looks like you want to add an additional method to JPanel.

Ok, that would require you to create a custom instance of a JPanel like this:

public class MyPanel extends JPanel {

    public MyPanel() {
        super();   
    }


    public int[][] getRandomMatrix() {
         int[][] randomMatrix = new int[10][10];
         for (int r = 0; r < randomMatrix.length; r++) {
             for (int c = 0; c < randomMatrix[r].length; c++) {
             randomMatrix[r][c] = (int)(Math.random() * 2);
         }
     }
    return randomMatrix;
   }
}

And instead of adding a pre-rolled JPanel to the frame, you would add an instance of 'MyPanel' to the frame instead.

public static void addComponentsToPane(Container pane) {

if (RIGHT_TO_LEFT) {
    pane.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);
}

MyPanel array;
JButton button;
pane.setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();

if (shouldFill) {
    c.fill = GridBagConstraints.HORIZONTAL;
}

button = new JButton("Reset to 0");
pane.add(button, c);

array = new MyPanel();
pane.add(myPanel, c);

}

private static void createAndShowGUI() {
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
addComponentsToPane(frame.getContentPane());
frame.pack();
frame.setVisible(true);
}



public static void main(String[] args) {
   javax.swing.SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            createAndShowGUI();
        }
  });
}