带有 GridLayout JFrame 的 JPanels 内的 JButtons [英] JButtons inside JPanels with a GridLayout JFrame

问题描述

我有一个 JFrame，它设置为大小为 NxN 的 GridLayout.N 由用户在程序开始时作为命令行给出.NxN 模式中的 JButton 被添加到 JPanels 的窗口中，由 GridLayout 设置位置(我认为).

I have one JFrame that is set to a GridLayout of size NxN. N is given by the user as a command line at the start of the program. JButtons in an NxN pattern are added to the window in JPanels, set in location by GridLayout (I think).

是否每个 JButton 都需要自己的 JPanel 才能使用 GridLayout?我的印象是您可以为所有按钮只设置一个 JPanel，并将 JPanel 设置为 JButton 的 GridLayout.我想在按钮数组的左侧添加另一个 JPanel，以在同一个左侧 JPanel 中显示按钮点击 (JLabel) 和重置按钮.

Does each JButton need its own JPanel to use GridLayout? I'm under the impression that you can set up just one JPanel for all the buttons and set the JPanel to a GridLayout for the JButtons. I want to add another JPanel to the left of the button array to display button clicks (JLabel) and a reset button within that same left JPanel.

这是我的(一小部分)代码，其中 N 由用户给出，system 是我的后台进程类，ButtonEvent 是 ActionListener/actionPerformed 的类:

Here is (a little of) my code, where N is given by the user, system is my background processes class, and ButtonEvent is the class for ActionListener/actionPerformed:

JFrame window = new JFrame("");
GridLayout layout = new GridLayout(N,N);
window.setLayout(layout);

for (int row = 0; row < N; row++){
    for (int col = 0; col < N; col++){
        JPanel panel = new JPanel();
        JButton b = new JButton ("("+row+","+col+")");
        window.add(b).setLocation(row, col);
        panel.add(b);
        b.addActionListener(new ButtonEvent(b, system, row, col));
        window.add(panel);
    }
}

window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
window.pack();
window.setVisible(true);

这就是我所拥有的 (N=4):

And this is what I have (N=4):

http://i.imgur.com/nbQoM.png

这是(大约)我正在寻找的内容(N=4):

Here is (approximately) what I am looking for (N=4):

http://i.imgur.com/SiVWO.png

我需要/想要的只是两个(或更多)JPanels，它们的设置大致如上，而且我尝试过的所有布局管理器都不能很好地与 GridLayout 布局 JFrame 配合使用.

All I need/want is two (or more) JPanels that are set up roughly like above, and all the layout managers I've tried don't play nice with the GridLayout layout JFrame.

推荐答案

这里试试这个代码示例:

Here try this code example:

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class LayoutExample extends JFrame
{
    private static final String INITIAL_TEXT = "Nothing Pressed";
    private static final String ADDED_TEXT = " was Pressed";
    private JLabel positionLabel;
    private JButton resetButton;
    private static int gridSize = 4;

    public LayoutExample()
    {
        super("Layout Example");
    }

    private void createAndDisplayGUI()
    {       
        setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

        JPanel contentPane = new JPanel();
        contentPane.setLayout(new FlowLayout(FlowLayout.LEFT, 20, 20));
        contentPane.setBorder(BorderFactory.createLineBorder(Color.DARK_GRAY, 2));

        JPanel leftPanel = new JPanel();
        leftPanel.setBorder(BorderFactory.createLineBorder(Color.DARK_GRAY, 2));
        leftPanel.setLayout(new BoxLayout(leftPanel, BoxLayout.Y_AXIS));    
        JPanel labelPanel = new JPanel();
        positionLabel = new JLabel(INITIAL_TEXT, JLabel.CENTER);
        JPanel buttonLeftPanel = new JPanel();
        resetButton = new JButton("Reset");
        resetButton.addActionListener(new ActionListener()
        {
            public void actionPerformed(ActionEvent ae)
            {
                positionLabel.setText(INITIAL_TEXT);
            }
        });
        labelPanel.add(positionLabel);
        buttonLeftPanel.add(resetButton);
        leftPanel.add(labelPanel);
        leftPanel.add(buttonLeftPanel);

        contentPane.add(leftPanel);

        JPanel buttonPanel = new JPanel();
        buttonPanel.setLayout(new GridLayout(gridSize, gridSize, 10, 10));
        for (int i = 0; i < gridSize; i++)
        {
            for (int j = 0; j < gridSize; j++)
            {
                JButton button = new JButton("(" + i + ", " + j + ")");
                button.setActionCommand("(" + i + ", " + j + ")");
                button.addActionListener(new ActionListener()
                {
                    public void actionPerformed(ActionEvent ae)
                    {
                        JButton but = (JButton) ae.getSource();
                        positionLabel.setText(
                            but.getActionCommand() + ADDED_TEXT);                           
                    }
                });
                buttonPanel.add(button);
            }
        }
        contentPane.add(buttonPanel);

        setContentPane(contentPane);
        pack();
        setLocationByPlatform(true);
        setVisible(true);
    }

    public static void main(String[] args)
    {
        if (args.length > 0)
        {
            gridSize = Integer.parseInt(args[0]);
        }
        SwingUtilities.invokeLater(new Runnable()
        {
            public void run()
            {
                new LayoutExample().createAndDisplayGUI();
            }
        });
    }
}

输出:

这篇关于带有 GridLayout JFrame 的 JPanels 内的 JButtons的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！