java - 如何使用 2 个 JPanel 对象对齐 JButton 以形成基本的 java GUI

Question

我正在尝试重新创建以下极其基本的 GUI:

我的输出如下:

我在格式化 JButton 时遇到了困难。一方面，无论我做什么，我都无法获得第二个面板，即在第一个面板下方显示的“shapePane”，其次是“colorPane”，我无法正确地使按钮的 y 轴更大以使它们更胖外貌。此外，顶部面板“shapePane”似乎会随着窗口大小的调整而动态移动，而第二个“colorPane”则保持在固定位置，无论窗口大小如何调整。

如果有人可以提供一些帮助，我将不胜感激

到目前为止我的代码如下:

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

public class GUI extends JFrame implements ActionListener, WindowListener
{
private JButton circleButton;
private JButton rectangleButton;
private JButton redButton;
private JButton greenButton;
private JButton blueButton;
private JButton exitButton;
private JTextField textField1;
private JLabel label1;
private JPanel contentPane;
private JPanel colorPane;
private JPanel shapePane;
private JFrame contentFrame;
private int count;

public GUI (String title)
{
    super(title);

    //setResizable(false);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    //setBounds(100, 100, 945, 580);

    //contentFrame = new JFrame();
    //contentPane = new JPanel();
    //contentFrame.add(contentPane);
    //contentPane.setBorder(new LineBorder(new Color(50, 5, 232), 4, true));

    //setContentPane(contentPane);
    //contentPane.setLayout(null);

    colorPane = new JPanel();
    //colorPane.setBorder(new LineBorder(new Color(34, 174, 82), 1, true));
    colorPane.setBounds(10, 32, 515, 125);

    //contentPane.add(colorPane);
    //colorPane.setLayout(null);


    shapePane = new JPanel();
    shapePane.setBounds(10, 165, 515, 315);
    //shapePane.setBorder(new LineBorder(new Color(34, 174, 82), 1, true));

    //contentPane.add(shapePane);
    //shapePane.setLayout(null);


    circleButton = new JButton("Circle");
    circleButton.setHorizontalAlignment(SwingConstants.LEFT);
    rectangleButton = new JButton("Rectangle");
    rectangleButton.setHorizontalAlignment(SwingConstants.LEFT);
    greenButton = new JButton("Green");
    redButton = new JButton("Red");
    blueButton = new JButton("Blue");
    exitButton = new JButton("Exit");
    textField1 = new JTextField(20);
    label1 = new JLabel("current time here");


    colorPane.add(redButton, BorderLayout.CENTER);
    colorPane.add(greenButton, BorderLayout.CENTER);
    colorPane.add(blueButton, BorderLayout.CENTER);


    shapePane.add(rectangleButton, BorderLayout.SOUTH);
    shapePane.add(circleButton, BorderLayout.SOUTH);
    shapePane.add(exitButton, BorderLayout.SOUTH);

    getContentPane().add(textField1, BorderLayout.EAST);
    getContentPane().add(label1, BorderLayout.WEST);



    getContentPane().add(colorPane, BorderLayout.CENTER);
    //contentFrame.add(colorPane);
    getContentPane().add(shapePane, BorderLayout.CENTER);
    //contentFrame.add(shapePane);
}

@Override
public void windowOpened(WindowEvent e) {
    // TODO Auto-generated method stub

}

@Override
public void windowClosing(WindowEvent e) 
{
    System.exit(0);

}

@Override
public void windowClosed(WindowEvent e) {
    // TODO Auto-generated method stub

}

@Override
public void windowIconified(WindowEvent e) {
    // TODO Auto-generated method stub

}

@Override
public void windowDeiconified(WindowEvent e) {
    // TODO Auto-generated method stub

}

@Override
public void windowActivated(WindowEvent e) {
    // TODO Auto-generated method stub

}

@Override
public void windowDeactivated(WindowEvent e) {
    // TODO Auto-generated method stub

}

@Override
public void actionPerformed(ActionEvent e) {
    // TODO Auto-generated method stub

}

}

Answer 1

以下内容应该可以帮助您入门:

设置标签的垂直和水平位置，使其显示在左下角和其所需的宽度。为了获得更大的布局灵 active ，请考虑在 JPanel 中扭曲它:

    label1 = new JLabel("current time here");
    label1.setVerticalAlignment(SwingConstants.BOTTOM);
    label1.setHorizontalAlignment(SwingConstants.LEFT);
    label1.setPreferredSize(new Dimension(200, 0)); //height is set by the layout manger
    getContentPane().add(label1, BorderLayout.WEST);

使用 GridLayout 作为按钮 Pane :

    colorPane = new JPanel();
    colorPane.setLayout(new GridLayout(2, 3));

初始化按钮并将它们一一添加到网格 Pane 中:

    redButton = makeButton("Red");
    colorPane.add(redButton);

其中 makeButton 是为避免重复代码而实现的方法:

private JButton makeButton(String text) {
    JButton b = new JButton(text);
    b.setHorizontalAlignment(SwingConstants.LEFT);
    b.addActionListener(this);
    b.setPreferredSize(new Dimension(125, 55)); //set preferred and let Layout manager do its work
    return b;
}

设置文本区域的列数。它的高度由布局管理器设置:

textArea = new JTextArea(0,20);
getContentPane().add(textArea, BorderLayout.EAST);

把它们放在一起:

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.SwingConstants;

public class GUI extends JFrame implements ActionListener
{
    private final JButton circleButton, rectangleButton, redButton;
    private final JButton greenButton, blueButton, exitButton;
    private final JTextArea textArea;
    private final JLabel label1;
    private final JPanel colorPane;

    private static final int ROWS = 2, COLS = 3;

    public GUI (String title)
    {
        super(title);

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //set label's vertical and horizontal position so it appears in the bottom left
        //and and its desired width
        //for more layout flexibility consider warping it in a JFrame
        label1 = new JLabel("current time here");
        label1.setVerticalAlignment(SwingConstants.BOTTOM);
        label1.setHorizontalAlignment(SwingConstants.LEFT);
        label1.setPreferredSize(new Dimension(200, 0)); //height is set by the layout manger
        getContentPane().add(label1, BorderLayout.WEST);

        //use a GridLayout for the buttons pane
        colorPane = new JPanel();
        colorPane.setLayout(new GridLayout(ROWS, COLS));
        getContentPane().add(colorPane, BorderLayout.CENTER);//each BorderLayout position can hold ONE component

        redButton = makeButton("Red");
        colorPane.add(redButton);
        greenButton = makeButton("Green");
        colorPane.add(greenButton);
        blueButton = makeButton("Blue");
        colorPane.add(blueButton);
        rectangleButton = makeButton("Rectangle");
        colorPane.add(rectangleButton);
        circleButton = makeButton("Circle");
        colorPane.add(circleButton);
        exitButton = makeButton("Exit");
        colorPane.add(exitButton);

        //set the text area number of columns. Its height is set by the layout manger
        textArea = new JTextArea(0,20);
        getContentPane().add(textArea, BorderLayout.EAST);

        pack();
    }

    private JButton makeButton(String text) {
        JButton b = new JButton(text);
        b.setHorizontalAlignment(SwingConstants.LEFT);
        b.addActionListener(this);
        b.setPreferredSize(new Dimension(125, 55)); //set preferred and let Layout manager do its work
        return b;
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        System.out.println(((JButton)e.getSource()).getText()+ " button pressed");
    }

    public static void main(String[] args) {
        new GUI("My Gui").setVisible(true);
    }
}

---

一个简单的增强功能可以将所有按钮引用存储在 Map 中:

public class GUI extends JFrame implements ActionListener
{
    private Map <String, JButton> buttons; // a map to hold references to all buttons 
    private final JTextArea textArea;
    private final JLabel label1;
    private final JPanel colorPane;

    private static final int ROWS = 2, COLS = 3;
    private static final String[] BUTTON_LABELS = {"Red","Green", "Blue", "Rectangle", "Circle", "Exit"};

    public GUI (String title)
    {
        super(title);
        buttons = new HashMap<>();
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //set label's vertical and horizontal position so it appears in the bottom left
        //and and its desired width
        //for more layout flexibility consider warping it in a JFrame
        label1 = new JLabel("current time here");
        label1.setVerticalAlignment(SwingConstants.BOTTOM);
        label1.setHorizontalAlignment(SwingConstants.LEFT);
        label1.setPreferredSize(new Dimension(200, 0)); //height is set by the layout manger
        getContentPane().add(label1, BorderLayout.WEST);

        //use a GridLayout for the buttons pane
        colorPane = new JPanel();
        colorPane.setLayout(new GridLayout(ROWS, COLS));
        getContentPane().add(colorPane, BorderLayout.CENTER);//each BorderLayout position can hold ONE component

        for(String text : BUTTON_LABELS){
            JButton button = makeButton(text);
            colorPane.add(button);
            buttons.put(text, button);
        }

        //set the text area number of columns. Its height is set by the layout manger
        textArea = new JTextArea(0,20);
        getContentPane().add(textArea, BorderLayout.EAST);

        pack();
    }

    private JButton makeButton(String text) {
        JButton b = new JButton(text);
        b.setHorizontalAlignment(SwingConstants.LEFT);
        b.addActionListener(this);
        b.setPreferredSize(new Dimension(125, 55)); //set preferred and let Layout manager do its work
        return b;
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        System.out.println(((JButton)e.getSource()).getText()+ " button pressed");
    }

    public static void main(String[] args) {
        new GUI("My Gui").setVisible(true);
    }
}