how to properly set size of JButton with image?

问题

This is what I have now:

This is what I want the image to look like:

I have two java files, one extends JFrame and part with Jpanel looks basically

 ShinyButtons panel = new ShinyButtons(); 

 panel.setLocation(10, 10);

 getContentPane().add(panel); 

another one extends JPanel with JButtons import javax.swing.*;

public class ShinyButtons extends JPanel{ 
public static byte RED = 0; 
public static byte ORANGE = 1; 
public static byte YELLOW = 2; 
public static byte GREEN = 3; 
public static byte BLUE = 4; 
public static byte LIGHT_GRAY = 5; 
public static byte DARK_GRAY = 6; 

public static byte ROWS = 8; 

private byte[][] buttonTable; 

public ShinyButtons() { 
    buttonTable = new byte[ROWS][ROWS]; 
    resetButtons();
    setBorder(BorderFactory.createEmptyBorder());
    setSize(552,552); 

    ImageIcon[] icons = {new ImageIcon("RedButton.png"), new ImageIcon("OrangeButton.png"), new ImageIcon("YellowButton.png"),
               new ImageIcon("GreenButton.png"), new ImageIcon("BlueButton.png"), new ImageIcon("LightGrayButton.png"),
               new ImageIcon("DarkGrayButton.png")};


    for (int row=0; row<8; row++){
        for (int col=0; col<8; col++){
            JButton buttons = new JButton(); 
            buttons.setSize(69,69); 
            buttons.setIcon(icons[(byte)(Math.random()*7)]);                
            add(buttons); 
            buttons.setLocation(row*69, col*69);
            buttons.setBorder(BorderFactory.createEmptyBorder());
        }
    }
} 

private void resetButtons() { 
    for (int r=0; r<ROWS; r++) 
        for (int c=0; c<ROWS; c++) 
            buttonTable[r][c] = (byte)(Math.random()*7); 
} 

public byte getButton(int r, int c) { return buttonTable[r][c]; }
}

回答1:

"how to properly set size of JButton with image?"

Don't set the sizes at all Use a Layout manager. See Laying out Components Within a Container to learn the different layout managers. The most obvious one is GridLayout that will layout your components in a grid of a size defined by you. If you look at the method below, you will see I use a GridLayout with 8 rows and 8 cols. The method takes in a dynamic grid size. I passed 8 to it. The all you have to do is all the images/labels to the panel. No need to specify location/size. The GridLayout will take care of that for you.

private JPanel createPanel(ImageIcon[] icons, int gridSize) {
    Random random = new Random();
    JPanel panel = new JPanel(new GridLayout(gridSize, gridSize));
    for (int i = 0; i < gridSize * gridSize; i++) {
        int index = random.nextInt(icons.length);
        JLabel label = new JLabel(icons[index]);
        label.setBorder(new LineBorder(Color.GRAY, 2));
        panel.add(label);
    }
    return panel;
}

Full Code

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.util.Random;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.border.LineBorder;

public class CircleImages {

    public CircleImages() {
        ImageIcon[] icons = createImageIcons();
        JPanel iconPanel = createPanel(icons, 8);

        JPanel bottomLeftPanel = new JPanel(new FlowLayout(FlowLayout.LEADING));
        bottomLeftPanel.add(new JLabel("Score: "));
        bottomLeftPanel.add(new JTextField(10));

        JPanel bottomRightPanel = new JPanel(new FlowLayout(FlowLayout.TRAILING));
        bottomRightPanel.add(new JButton("New Game"));
        bottomRightPanel.add(new JButton("Quit"));

        JPanel bottomPanel = new JPanel(new GridLayout(1, 2));
        bottomPanel.add(bottomLeftPanel);
        bottomPanel.add(bottomRightPanel);

        JFrame frame = new JFrame();
        frame.add(iconPanel);
        frame.add(bottomPanel, BorderLayout.PAGE_END);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    private JPanel createPanel(ImageIcon[] icons, int gridSize) {
        Random random = new Random();
        JPanel panel = new JPanel(new GridLayout(gridSize, gridSize));
        for (int i = 0; i < gridSize * gridSize; i++) {
            int index = random.nextInt(icons.length);
            JLabel label = new JLabel(icons[index]);
            label.setBorder(new LineBorder(Color.GRAY, 2));
            panel.add(label);
        }
        return panel;
    }

    private ImageIcon[] createImageIcons() {
        String[] files = {"blackcircle.png",
            "bluecircle.png",
            "greencircle.png",
            "greycircle.png",
            "orangecircle.png",
            "redcircle.png",
            "yellowcircle.png"
        };
        ImageIcon[] icons = new ImageIcon[files.length];
        for (int i = 0; i < files.length; i++) {
            icons[i] = new ImageIcon(getClass().getResource("/circles/" + files[i]));
        }
        return icons;
    }

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

回答2:

The easiest way would be something like this:

button.setSize(imageIcon.getIconWidth, imageIcon.getIconHeight);

来源：https://stackoverflow.com/questions/22108540/how-to-properly-set-size-of-jbutton-with-image