几个简单的JAVA GUI练习

Author Avatar
EmptinessBoy 5月 19, 2020
  • 在其它设备中阅读本文章

最近在听 NEU 的 JAVA 慕课,然后有两个简单的 GUI 课后练习:

菜单栏相关练习

编写如图所示应用程序,单击选择菜单项退出后,显示下面的请选择对话框,选择是结束程序,选择否显示下面的消息对话框。

a.jpg

题目要求使用菜单栏 JMenuBar 和 菜单项 JMenuItem, 很遗憾 IEDA 所提供的 SwingGUIdesigner 并没有默认提高 菜单栏 和 菜单项的选则。因此这里被迫使用了 JFormDesigner 来创建可视化界面:

jfd-homework1.png

这里,题目要求的两个 optionPane 也是可以先在 jFromDesinger 中先画好的。这样就可以不用手动初始化了。

至此,系统自动生成的代码如下:

private void initComponents() {
    // JFormDesigner - Component initialization - DO NOT MODIFY  //GEN-BEGIN:initComponents
    menuBar1 = new JMenuBar();
    menuFile = new JMenu();
    menuItemOpen = new JMenuItem();
    menuItemExit = new JMenuItem();
    menuEidt = new JMenu();
    menuForm = new JMenu();
    optionPaneChoose = new JOptionPane();
    optionPaneNo = new JOptionPane();

    //======== this ========
    setTitle("EmptinessBoy\u4f5c\u4e1a");
    Container contentPane = getContentPane();
    contentPane.setLayout(new GridLayout(3, 4));

    //======== menuBar1 ========
    {

        //======== menuFile ========
        {
            menuFile.setText("\u6587\u4ef6");

            //---- menuItemOpen ----
            menuItemOpen.setText("\u6253\u5f00");
            menuFile.add(menuItemOpen);

            //---- menuItemExit ----
            menuItemExit.setText("\u9000\u51fa");
            menuItemExit.addActionListener(e -> menuItemExitActionPerformed(e));
            menuFile.add(menuItemExit);
        }
        menuBar1.add(menuFile);

        //======== menuEidt ========
        {
            menuEidt.setText("\u7f16\u8f91");
        }
        menuBar1.add(menuEidt);

        //======== menuForm ========
        {
            menuForm.setText("\u7a97\u53e3");
        }
        menuBar1.add(menuForm);
    }
    setJMenuBar(menuBar1);
    setSize(445, 315);
    setLocationRelativeTo(getOwner());
    // JFormDesigner - End of component initialization  //GEN-END:initComponents
}

// JFormDesigner - Variables declaration - DO NOT MODIFY  //GEN-BEGIN:variables
private JMenuBar menuBar1;
private JMenu menuFile;
private JMenuItem menuItemOpen;
private JMenuItem menuItemExit;
private JMenu menuEidt;
private JMenu menuForm;
private JOptionPane optionPaneChoose;
private JOptionPane optionPaneNo;
// JFormDesigner - End of variables declaration  //GEN-END:variables

为了使程序完成题目要求的功能,我们需要给菜单项 JMenuItem【menuItemExit】设置监听器。

事件监听代码:

optionPane 对话框写法

private void menuItemExitActionPerformed(ActionEvent e) {
    // TODO add your code here
    int i = optionPaneChoose.showConfirmDialog(null,"是否退出系统?","请选择", JOptionPane.YES_NO_OPTION);
    if(i==0)
        System.exit(0);
    else{
        //ConfirmDialog(null,"您选择了否!","消息",JOptionPane.YES_OPTION);
        optionPaneNo.showMessageDialog(null,"您选择了否","消息", JOptionPane.YES_OPTION);
    }
}

对于多选对话框,int i 的返回值就是指代了用户选中的 “是” 或 “否” 的值。一般情况下,选中是为 0.

optionPaneNo.showMessageDialog 显示一个消息提示
optionPaneChoose.showConfirmDialog 显示可确认对话框

设置点击关闭窗体的默认事件

只要在实现 JFrame 类的构造函数中加入一条

setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

即可轻松搞定。

最后,整体运行效果:

jfd-homework2.png

窗体相关练习

窗体中显示一个图片,用鼠标可以拖动图片到任意位置。

没错,作业只有这么简简单单一句话。然后我也天真的以为这是一道秒杀题。但是,往往是我太天真了(悲哀

头里的步骤并不难,这里使用 JFormDesigner 创建窗体。然后随便拖拽一个 JLable 用来存放图片。

jfd-homework3.png

下面是系统自动生成的代码(含后面加的监听器):

……
    private void initComponents() {
        // JFormDesigner - Component initialization - DO NOT MODIFY  //GEN-BEGIN:initComponents
        label1 = new JLabel();
        textField1 = new JTextField();

        //======== this ========
        setMinimumSize(new Dimension(500, 500));
        setTitle("EmptinessBoyMooc\u4f5c\u4e1a");
        var contentPane = getContentPane();

        //---- label1 ----
        label1.setIcon(null);
        label1.addMouseMotionListener(new MouseMotionAdapter() {
            @Override
            public void mouseDragged(MouseEvent e) {
                label1MouseDragged(e);
            }
        });
        label1.addMouseListener(new MouseAdapter() {
            @Override
            public void mousePressed(MouseEvent e) {
                label1MousePressed(e);
            }
        });

        //---- textField1 ----
        textField1.setText("\u6b64\u5904\u663e\u793a\u5750\u6807");

        GroupLayout contentPaneLayout = new GroupLayout(contentPane);
        contentPane.setLayout(contentPaneLayout);
        contentPaneLayout.setHorizontalGroup(
            contentPaneLayout.createParallelGroup()
                .addGroup(contentPaneLayout.createSequentialGroup()
                    .addGroup(contentPaneLayout.createParallelGroup(GroupLayout.Alignment.LEADING, false)
                        .addComponent(label1, GroupLayout.PREFERRED_SIZE, 100, GroupLayout.PREFERRED_SIZE)
                        .addGroup(contentPaneLayout.createSequentialGroup()
                            .addContainerGap()
                            .addComponent(textField1)))
                    .addContainerGap())
        );
        contentPaneLayout.setVerticalGroup(
            contentPaneLayout.createParallelGroup()
                .addGroup(contentPaneLayout.createSequentialGroup()
                    .addComponent(label1, GroupLayout.PREFERRED_SIZE, 100, GroupLayout.PREFERRED_SIZE)
                    .addPreferredGap(LayoutStyle.ComponentPlacement.RELATED, 302, Short.MAX_VALUE)
                    .addComponent(textField1, GroupLayout.PREFERRED_SIZE, GroupLayout.DEFAULT_SIZE, GroupLayout.PREFERRED_SIZE)
                    .addContainerGap())
        );
        pack();
        setLocationRelativeTo(getOwner());
        // JFormDesigner - End of component initialization  //GEN-END:initComponents
    }

    // JFormDesigner - Variables declaration - DO NOT MODIFY  //GEN-BEGIN:variables
    private JLabel label1;
    private JTextField textField1;
    // JFormDesigner - End of variables declaration  //GEN-END:variables
}

到这里,我们需要给 jlable 设置 icon,这里将设置 icon 的代码放到构造函数中:

Jlabel 设置 icon 方法

public MovePic() {
    initComponents();
    setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    ImageIcon i = new ImageIcon("src/logo.png");
    Image pic = i.getImage().getScaledInstance(100,100,Image.SCALE_DEFAULT);
    ImageIcon ico = new ImageIcon(pic);
    label1.setIcon(ico);
}

现在是不是只要给 存放了图片的 jlable 设置 MouseDragged 鼠标拖拽监听函数呢?

最开始一脸小白的我确实是这么想的,然后写下了简单的

错误代码:
x = e.getX();
y = e.getY();
textField1.setText(x+","+y);
label1.setLocation(x,y);

网上都说了 e.getX(); e.getY(); 不就是获取当前是鼠标位置嘛。(呵呵

然而在实际测试中发现,实际上,这两个获取到的都是以 jlable 为容器,鼠标在 jlable 中的相对位置。因此单纯这样的代码无法实现所需要的功能。

那么,一心想偷懒的我想,那么只要针对 Jlable 的父容器设置鼠标监听器来改变坐标不就完了?(理想很美好,现实确是:

因为子容器遮挡了父容器,当鼠标移动到 Jlable 上时,设置在父容器 JFrame 的监听器就失效了!!

只有鼠标移出图片的时候,才能正确获取针对窗体的坐标。

终极坐标解决方案

那么只能使出大杀器了,(用我小学的算数水平,通过绝对坐标加减来获取位置了

经过查找文档,可知:

e.getXOnScreen() e.getYOnScreen() 可以用来获取鼠标在整个屏幕的绝对位置,而 this.getX() this.getY()可以获得当前窗体在屏幕中的左上角位置。

那么?!

只要使用 x = e.getXOnScreen()-this.getX() 就可以通过计算获得鼠标在窗体内部的相对位置啦!!!

但是这时候还是有些小小的瑕疵 ——鼠标拖拽后,显示的位置是以鼠标结束位置作为左上角定点的,拖拽感觉不够自然。

修复的方法很简单。既然 e.getX() 可以获取当前鼠标相对于图片(jlable)的相对位置,那么只要在我们刚才获取的 x 减去 这个内部的相对位置就完美啦!!注意这个坐标需要在刚开始按下鼠标时获取才有用,因此需要放在 MousePressed 监听器中。

最后附上代码:

public class MovePic extends JFrame {
    int x,y,a,b;
    public static void main(String[] args) {
        new MovePic().setVisible(true);
    }
    public MovePic() {
        initComponents();
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        ImageIcon i = new ImageIcon("src/logo.png");
        Image pic = i.getImage().getScaledInstance(100,100,Image.SCALE_DEFAULT);
        ImageIcon ico = new ImageIcon(pic);
        label1.setIcon(ico);
    }

    private void label1MouseDragged(MouseEvent e) {
        // TODO add your code here
        x = e.getXOnScreen()-this.getX()-a;
        y = e.getYOnScreen()-this.getY()-b-20;
        textField1.setText(x+","+y);
        label1.setLocation(x,y);
    }


    private void label1MousePressed(MouseEvent e) {
        // TODO add your code here
        a = e.getX();
        b = e.getY();
    }
……

运行效果:

e18f47190defc5112b413d963c2e3a72.gif

nice!又是洗洗睡的一天(PS,最近腰疼犯了,睡觉保命要紧【滑稽】

控件和监听器练习

题目要求:使用 Java 实现一个RGB调色板程序,点击加减按钮可以调整RGB数值并显示颜色

由于已经比较习惯了 JFormDesigner 那么完成这个任务也靠Ta啦!

设计界面

jfd-colorpanel.png

这里外层的 Jframe 使用了 IntelijGridLayOut ,比起标准的 GridLayout 可以自由调整 margin,以及内部的浮动(有点像安卓里的 Gravaty

内部划分了两个 panel 用于摆放控件,下方的 panel 则用来显示实时的颜色输出

划分完成 UI ,并设置完成事件监听器后,系统就自动生成了 UI 相关的代码

……
    private void initComponents() {
        // JFormDesigner - Component initialization - DO NOT MODIFY  //GEN-BEGIN:initComponents
        panelSetColor = new JPanel();
        labelRed = new JLabel();
        buttonSubRed = new JButton();
        textFieldRed = new JTextField();
        buttonAddRed = new JButton();
        labelGreen = new JLabel();
        buttonSubGreen = new JButton();
        textFieldGreen = new JTextField();
        buttonAddGreen = new JButton();
        labelBlue = new JLabel();
        buttonSubBlue = new JButton();
        textFieldBlue = new JTextField();
        buttonAddBlue = new JButton();
        panelColor = new JPanel();
        labelShowColor = new JLabel();

        //======== this ========
        setTitle("2018010587-\u80e1\u6653\u5e06\uff08\u8c03\u8272\u677f\uff09");
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        setMinimumSize(new Dimension(550, 350));
        setFont(new Font(Font.DIALOG, Font.PLAIN, 16));
        setBackground(Color.white);
        Container contentPane = getContentPane();
        contentPane.setLayout(new GridLayoutManager(4, 1, new Insets(0, 20, 20, 20), 0, 5));

        //======== panelSetColor ========
        {
            panelSetColor.setFont(panelSetColor.getFont().deriveFont(panelSetColor.getFont().getSize() + 4f));
            panelSetColor.setLayout(new GridLayoutManager(3, 4, new Insets(20, 0, 10, 0), 3, 3));

            //---- labelRed ----
            labelRed.setText("\u7ea2\u8272 R");
            labelRed.setForeground(Color.red);
            labelRed.setFont(labelRed.getFont().deriveFont(labelRed.getFont().getStyle() | Font.BOLD, labelRed.getFont().getSize() + 4f));
            panelSetColor.add(labelRed, new GridConstraints(0, 0, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- buttonSubRed ----
            buttonSubRed.setText("\u51cf\u5c11");
            buttonSubRed.setFont(buttonSubRed.getFont().deriveFont(buttonSubRed.getFont().getSize() + 4f));
            buttonSubRed.addActionListener(e -> buttonSubRedActionPerformed(e));
            panelSetColor.add(buttonSubRed, new GridConstraints(0, 1, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- textFieldRed ----
            textFieldRed.setText("155");
            textFieldRed.setFont(textFieldRed.getFont().deriveFont(textFieldRed.getFont().getSize() + 4f));
            panelSetColor.add(textFieldRed, new GridConstraints(0, 2, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_HORIZONTAL,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- buttonAddRed ----
            buttonAddRed.setText("\u589e\u52a0");
            buttonAddRed.setFont(buttonAddRed.getFont().deriveFont(buttonAddRed.getFont().getSize() + 4f));
            buttonAddRed.addActionListener(e -> buttonAddRedActionPerformed(e));
            panelSetColor.add(buttonAddRed, new GridConstraints(0, 3, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- labelGreen ----
            labelGreen.setText("\u7eff\u8272 G");
            labelGreen.setForeground(new Color(0, 204, 51));
            labelGreen.setFont(labelGreen.getFont().deriveFont(labelGreen.getFont().getStyle() | Font.BOLD, labelGreen.getFont().getSize() + 4f));
            panelSetColor.add(labelGreen, new GridConstraints(1, 0, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- buttonSubGreen ----
            buttonSubGreen.setText("\u51cf\u5c11");
            buttonSubGreen.setFont(buttonSubGreen.getFont().deriveFont(buttonSubGreen.getFont().getSize() + 4f));
            buttonSubGreen.addActionListener(e -> buttonSubGreenActionPerformed(e));
            panelSetColor.add(buttonSubGreen, new GridConstraints(1, 1, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- textFieldGreen ----
            textFieldGreen.setText("155");
            textFieldGreen.setFont(textFieldGreen.getFont().deriveFont(textFieldGreen.getFont().getSize() + 4f));
            panelSetColor.add(textFieldGreen, new GridConstraints(1, 2, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_HORIZONTAL,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- buttonAddGreen ----
            buttonAddGreen.setText("\u589e\u52a0");
            buttonAddGreen.setFont(buttonAddGreen.getFont().deriveFont(buttonAddGreen.getFont().getSize() + 4f));
            buttonAddGreen.addActionListener(e -> buttonAddGreenActionPerformed(e));
            panelSetColor.add(buttonAddGreen, new GridConstraints(1, 3, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- labelBlue ----
            labelBlue.setText("\u84dd\u8272 B");
            labelBlue.setForeground(new Color(0, 102, 255));
            labelBlue.setFont(labelBlue.getFont().deriveFont(labelBlue.getFont().getStyle() | Font.BOLD, labelBlue.getFont().getSize() + 4f));
            panelSetColor.add(labelBlue, new GridConstraints(2, 0, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- buttonSubBlue ----
            buttonSubBlue.setText("\u51cf\u5c11");
            buttonSubBlue.setFont(buttonSubBlue.getFont().deriveFont(buttonSubBlue.getFont().getSize() + 4f));
            buttonSubBlue.addActionListener(e -> buttonSubBlueActionPerformed(e));
            panelSetColor.add(buttonSubBlue, new GridConstraints(2, 1, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- textFieldBlue ----
            textFieldBlue.setText("155");
            textFieldBlue.setFont(textFieldBlue.getFont().deriveFont(textFieldBlue.getFont().getSize() + 4f));
            panelSetColor.add(textFieldBlue, new GridConstraints(2, 2, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_HORIZONTAL,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- buttonAddBlue ----
            buttonAddBlue.setText("\u589e\u52a0");
            buttonAddBlue.setFont(buttonAddBlue.getFont().deriveFont(buttonAddBlue.getFont().getSize() + 4f));
            buttonAddBlue.addActionListener(e -> buttonAddBlueActionPerformed(e));
            panelSetColor.add(buttonAddBlue, new GridConstraints(2, 3, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));
        }
        contentPane.add(panelSetColor, new GridConstraints(0, 0, 1, 1,
            GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_BOTH,
            GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
            GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
            null, null, null));

        //======== panelColor ========
        {
            panelColor.setLayout(new GridLayoutManager(1, 1, new Insets(0, 10, 0, 10), 0, 0));

            //---- labelShowColor ----
            labelShowColor.setText("\u6b64\u5904\u663e\u793a\u6700\u7ec8\u989c\u8272");
            panelColor.add(labelShowColor, new GridConstraints(0, 0, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));
        }
        contentPane.add(panelColor, new GridConstraints(2, 0, 1, 1,
            GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_BOTH,
            GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
            GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
            null, null, null));
        pack();
        setLocationRelativeTo(getOwner());
        // JFormDesigner - End of component initialization  //GEN-END:initComponents
    }

    // JFormDesigner - Variables declaration - DO NOT MODIFY  //GEN-BEGIN:variables
    private JPanel panelSetColor;
    private JLabel labelRed;
    private JButton buttonSubRed;
    private JTextField textFieldRed;
    private JButton buttonAddRed;
    private JLabel labelGreen;
    private JButton buttonSubGreen;
    private JTextField textFieldGreen;
    private JButton buttonAddGreen;
    private JLabel labelBlue;
    private JButton buttonSubBlue;
    private JTextField textFieldBlue;
    private JButton buttonAddBlue;
    private JPanel panelColor;
    private JLabel labelShowColor;
    // JFormDesigner - End of variables declaration  //GEN-END:variables
}

核心代码

第一步要解决的就是程序刚运行时显示的颜色。这里我给类创建了r,g,b三个整型的变量。

然后只要在构造函数中把 panel 的颜色设置成预设的 rgb 即可。这里使用了 .setBackground 方法来设置背景色值。

public class ColorPanel extends JFrame {
    int r=155,g=155,b=155;
    Color bgColor = new Color(r, g, b);//设置初始颜色
……

public ColorPanel() {
    initComponents();
    textFieldRed.setText(String.valueOf(r));
    textFieldGreen.setText(String.valueOf(g));
    textFieldBlue.setText(String.valueOf(b));
    panelColor.setBackground(bgColor);
}

接下来就是要通过按钮的按动来改变颜色了,这里以红色减少按钮为例:

private void buttonSubRedActionPerformed(ActionEvent e) {
    // TODO add your code here
    GetNum();
    if(r>0&&r<=255)
        r--;
    else
        System.out.println("红色已到临界值");
    ShowColor();
}

这段代码中,使用了我写的两个函数 GetNum() 和 ShowColor()。GetNum 的目的是获取两个按钮中的文本框的值,来允许程序运行的时候可以手动输入数值。而 showColor 则是因为每个按钮最后都有显示颜色的功能,这段代码可以用函数来做。

GetNum():

void GetNum(){
    //允许用户输入数值修改rgb
    r = Integer.parseInt(textFieldRed.getText());
    g = Integer.parseInt(textFieldGreen.getText());
    b = Integer.parseInt(textFieldBlue.getText());
}

ShowColor():

void ShowColor(){
    textFieldRed.setText(String.valueOf(r));
    textFieldGreen.setText(String.valueOf(g));
    textFieldBlue.setText(String.valueOf(b));
    bgColor = new Color(r,g,b);
    panelColor.setBackground(bgColor);
    panelColor.setBackground(bgColor);
    labelShowColor.setText("当前颜色16进制为:#"+Integer.toHexString(r)+Integer.toHexString(g)+Integer.toHexString(b));
}

最后附上运行效果:

hxftiaoseban.gif

完整代码:

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import com.intellij.uiDesigner.core.*;

/**
 * @author huxiaofan
 */
public class ColorPanel extends JFrame {
    int r=155,g=155,b=155;
    Color bgColor = new Color(r, g, b);//设置初始颜色
    public static void main(String[] args) {
        new ColorPanel().setVisible(true);


    }
    public ColorPanel() {
        initComponents();
        textFieldRed.setText(String.valueOf(r));
        textFieldGreen.setText(String.valueOf(g));
        textFieldBlue.setText(String.valueOf(b));
        panelColor.setBackground(bgColor);
    }

    void ShowColor(){
        textFieldRed.setText(String.valueOf(r));
        textFieldGreen.setText(String.valueOf(g));
        textFieldBlue.setText(String.valueOf(b));
        bgColor = new Color(r,g,b);
        panelColor.setBackground(bgColor);
        panelColor.setBackground(bgColor);
        labelShowColor.setText("当前颜色16进制为:#"+Integer.toHexString(r)+Integer.toHexString(g)+Integer.toHexString(b));
    }

    void GetNum(){
        //允许用户输入数值修改rgb
        r = Integer.parseInt(textFieldRed.getText());
        g = Integer.parseInt(textFieldGreen.getText());
        b = Integer.parseInt(textFieldBlue.getText());
    }

    private void buttonSubRedActionPerformed(ActionEvent e) {
        // TODO add your code here
        GetNum();
        if(r>0&&r<=255)
            r--;
        else
            System.out.println("红色已到临界值");
        ShowColor();
    }

    private void buttonAddRedActionPerformed(ActionEvent e) {
        // TODO add your code here
        GetNum();
        if(r>=0&&r<255)
            r++;
        else
            System.out.println("红色已到临界值");
        ShowColor();
    }

    private void buttonSubGreenActionPerformed(ActionEvent e) {
        // TODO add your code here
        GetNum();
        if(g>0&&g<=255)
            g--;
        else
            System.out.println("绿色已到临界值");
        ShowColor();
    }

    private void buttonAddGreenActionPerformed(ActionEvent e) {
        // TODO add your code here
        GetNum();
        if(g>=0&&g<255)
            g++;
        else
            System.out.println("绿色已到临界值");
        ShowColor();
    }

    private void buttonSubBlueActionPerformed(ActionEvent e) {
        // TODO add your code here
        GetNum();
        if(b>0&&b<=255)
            b--;
        else
            System.out.println("蓝色已到临界值");
        ShowColor();
    }

    private void buttonAddBlueActionPerformed(ActionEvent e) {
        // TODO add your code here
        GetNum();
        if(b>=0&&b<255)
            b++;
        else
            System.out.println("蓝色已到临界值");
        ShowColor();
    }



    private void initComponents() {
        // JFormDesigner - Component initialization - DO NOT MODIFY  //GEN-BEGIN:initComponents
        panelSetColor = new JPanel();
        labelRed = new JLabel();
        buttonSubRed = new JButton();
        textFieldRed = new JTextField();
        buttonAddRed = new JButton();
        labelGreen = new JLabel();
        buttonSubGreen = new JButton();
        textFieldGreen = new JTextField();
        buttonAddGreen = new JButton();
        labelBlue = new JLabel();
        buttonSubBlue = new JButton();
        textFieldBlue = new JTextField();
        buttonAddBlue = new JButton();
        panelColor = new JPanel();
        labelShowColor = new JLabel();

        //======== this ========
        setTitle("2018010587-\u80e1\u6653\u5e06\uff08\u8c03\u8272\u677f\uff09");
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        setMinimumSize(new Dimension(550, 350));
        setFont(new Font(Font.DIALOG, Font.PLAIN, 16));
        setBackground(Color.white);
        Container contentPane = getContentPane();
        contentPane.setLayout(new GridLayoutManager(4, 1, new Insets(0, 20, 20, 20), 0, 5));

        //======== panelSetColor ========
        {
            panelSetColor.setFont(panelSetColor.getFont().deriveFont(panelSetColor.getFont().getSize() + 4f));
            panelSetColor.setLayout(new GridLayoutManager(3, 4, new Insets(20, 0, 10, 0), 3, 3));

            //---- labelRed ----
            labelRed.setText("\u7ea2\u8272 R");
            labelRed.setForeground(Color.red);
            labelRed.setFont(labelRed.getFont().deriveFont(labelRed.getFont().getStyle() | Font.BOLD, labelRed.getFont().getSize() + 4f));
            panelSetColor.add(labelRed, new GridConstraints(0, 0, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- buttonSubRed ----
            buttonSubRed.setText("\u51cf\u5c11");
            buttonSubRed.setFont(buttonSubRed.getFont().deriveFont(buttonSubRed.getFont().getSize() + 4f));
            buttonSubRed.addActionListener(e -> buttonSubRedActionPerformed(e));
            panelSetColor.add(buttonSubRed, new GridConstraints(0, 1, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- textFieldRed ----
            textFieldRed.setText("155");
            textFieldRed.setFont(textFieldRed.getFont().deriveFont(textFieldRed.getFont().getSize() + 4f));
            panelSetColor.add(textFieldRed, new GridConstraints(0, 2, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_HORIZONTAL,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- buttonAddRed ----
            buttonAddRed.setText("\u589e\u52a0");
            buttonAddRed.setFont(buttonAddRed.getFont().deriveFont(buttonAddRed.getFont().getSize() + 4f));
            buttonAddRed.addActionListener(e -> buttonAddRedActionPerformed(e));
            panelSetColor.add(buttonAddRed, new GridConstraints(0, 3, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- labelGreen ----
            labelGreen.setText("\u7eff\u8272 G");
            labelGreen.setForeground(new Color(0, 204, 51));
            labelGreen.setFont(labelGreen.getFont().deriveFont(labelGreen.getFont().getStyle() | Font.BOLD, labelGreen.getFont().getSize() + 4f));
            panelSetColor.add(labelGreen, new GridConstraints(1, 0, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- buttonSubGreen ----
            buttonSubGreen.setText("\u51cf\u5c11");
            buttonSubGreen.setFont(buttonSubGreen.getFont().deriveFont(buttonSubGreen.getFont().getSize() + 4f));
            buttonSubGreen.addActionListener(e -> buttonSubGreenActionPerformed(e));
            panelSetColor.add(buttonSubGreen, new GridConstraints(1, 1, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- textFieldGreen ----
            textFieldGreen.setText("155");
            textFieldGreen.setFont(textFieldGreen.getFont().deriveFont(textFieldGreen.getFont().getSize() + 4f));
            panelSetColor.add(textFieldGreen, new GridConstraints(1, 2, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_HORIZONTAL,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- buttonAddGreen ----
            buttonAddGreen.setText("\u589e\u52a0");
            buttonAddGreen.setFont(buttonAddGreen.getFont().deriveFont(buttonAddGreen.getFont().getSize() + 4f));
            buttonAddGreen.addActionListener(e -> buttonAddGreenActionPerformed(e));
            panelSetColor.add(buttonAddGreen, new GridConstraints(1, 3, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- labelBlue ----
            labelBlue.setText("\u84dd\u8272 B");
            labelBlue.setForeground(new Color(0, 102, 255));
            labelBlue.setFont(labelBlue.getFont().deriveFont(labelBlue.getFont().getStyle() | Font.BOLD, labelBlue.getFont().getSize() + 4f));
            panelSetColor.add(labelBlue, new GridConstraints(2, 0, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- buttonSubBlue ----
            buttonSubBlue.setText("\u51cf\u5c11");
            buttonSubBlue.setFont(buttonSubBlue.getFont().deriveFont(buttonSubBlue.getFont().getSize() + 4f));
            buttonSubBlue.addActionListener(e -> buttonSubBlueActionPerformed(e));
            panelSetColor.add(buttonSubBlue, new GridConstraints(2, 1, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- textFieldBlue ----
            textFieldBlue.setText("155");
            textFieldBlue.setFont(textFieldBlue.getFont().deriveFont(textFieldBlue.getFont().getSize() + 4f));
            panelSetColor.add(textFieldBlue, new GridConstraints(2, 2, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_HORIZONTAL,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- buttonAddBlue ----
            buttonAddBlue.setText("\u589e\u52a0");
            buttonAddBlue.setFont(buttonAddBlue.getFont().deriveFont(buttonAddBlue.getFont().getSize() + 4f));
            buttonAddBlue.addActionListener(e -> buttonAddBlueActionPerformed(e));
            panelSetColor.add(buttonAddBlue, new GridConstraints(2, 3, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));
        }
        contentPane.add(panelSetColor, new GridConstraints(0, 0, 1, 1,
            GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_BOTH,
            GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
            GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
            null, null, null));

        //======== panelColor ========
        {
            panelColor.setLayout(new GridLayoutManager(1, 1, new Insets(0, 10, 0, 10), 0, 0));

            //---- labelShowColor ----
            labelShowColor.setText("\u6b64\u5904\u663e\u793a\u6700\u7ec8\u989c\u8272");
            panelColor.add(labelShowColor, new GridConstraints(0, 0, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));
        }
        contentPane.add(panelColor, new GridConstraints(2, 0, 1, 1,
            GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_BOTH,
            GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
            GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
            null, null, null));
        pack();
        setLocationRelativeTo(getOwner());
        // JFormDesigner - End of component initialization  //GEN-END:initComponents
    }

    // JFormDesigner - Variables declaration - DO NOT MODIFY  //GEN-BEGIN:variables
    private JPanel panelSetColor;
    private JLabel labelRed;
    private JButton buttonSubRed;
    private JTextField textFieldRed;
    private JButton buttonAddRed;
    private JLabel labelGreen;
    private JButton buttonSubGreen;
    private JTextField textFieldGreen;
    private JButton buttonAddGreen;
    private JLabel labelBlue;
    private JButton buttonSubBlue;
    private JTextField textFieldBlue;
    private JButton buttonAddBlue;
    private JPanel panelColor;
    private JLabel labelShowColor;
    // JFormDesigner - End of variables declaration  //GEN-END:variables
}

带IO操作的登录窗体

编写一个登录窗体,输入用户名和密码,验证通过显示登录成功的消息框,否则显示用户名或密码错误的消息框。用户名和密码存放在 c 盘 java 目录下的 login.txt 中,用文本信息存储,每行一个用户名和密码,用户名和密码用 # 分隔

核心代码

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.util.Arrays;
import javax.swing.*;
import com.intellij.uiDesigner.core.*;

/**
 * @author huxiaofan
 */
public class loginPanel extends JFrame {

    File f = new File("login.txt"); //创建一个用于读取用户名密码的文件对象

    public static void main(String[] args) {
        new loginPanel().setVisible(true); //显示窗体
    }
    public loginPanel() {
        initComponents();
    }

    private void buttonLoginActionPerformed(ActionEvent e) {
        // TODO add your code here
        if(doLogin())
            optionPaneok.showMessageDialog(null,"恭喜你登录成功!","登录成功",JOptionPane.INFORMATION_MESSAGE); //显示成功弹窗
        else
            optionPanefail.showMessageDialog(null, "用户名密码错误!", "登录失败",JOptionPane.ERROR_MESSAGE); //显示失败弹窗
    }

    boolean doLogin(){  //函数登录成功返回 true
        try {
            BufferedReader br = new BufferedReader(new FileReader(f));  //新建字符缓冲流
            String u = textFieldUserName.getText();  //获取用户输入在文本框的用户名
            String p = String.valueOf(passwordFieldPass.getPassword());  //获取用户输入在密码框的密码,要把原始的字符数组用 String.valueOf() 方法转为字符串
            String s;  //存放临时读取的每一行字符串
            while((s = br.readLine())!=null){
                String[] temp = s.split("#");  //拆分字符串
                if(temp[0].equals(u)&&temp[1].equals(p)){
                    System.out.println("登录成功");
                    return true;
                }
            }
            br.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return false;
    }

    private void button2ActionPerformed(ActionEvent e) {
        // TODO add your code here
    }
……

UI自动生成代码

……
    private void initComponents() {
        // JFormDesigner - Component initialization - DO NOT MODIFY  //GEN-BEGIN:initComponents
        panel1 = new JPanel();
        labelUser = new JLabel();
        textFieldUserName = new JTextField();
        labelPass = new JLabel();
        passwordFieldPass = new JPasswordField();
        buttonLogin = new JButton();
        optionPaneok = new JOptionPane();
        optionPanefail = new JOptionPane();

        //======== this ========
        setTitle("Emptinessboy \u6155\u8bfeIO\u4f5c\u4e1a");
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        setMinimumSize(new Dimension(420, 250));
        Container contentPane = getContentPane();
        contentPane.setLayout(new GridLayoutManager(2, 1, new Insets(0, 0, 5, 0), -1, -1));

        //======== panel1 ========
        {
            panel1.setMinimumSize(new Dimension(180, 90));
            panel1.setLayout(new GridLayoutManager(2, 2, new Insets(10, 30, 10, 60), 0, 10));

            //---- labelUser ----
            labelUser.setText("\u7528\u6237\u540d \uff1a");
            labelUser.setFont(labelUser.getFont().deriveFont(labelUser.getFont().getStyle() | Font.BOLD, labelUser.getFont().getSize() + 3f));
            panel1.add(labelUser, new GridConstraints(0, 0, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- textFieldUserName ----
            textFieldUserName.setFont(textFieldUserName.getFont().deriveFont(textFieldUserName.getFont().getSize() + 3f));
            panel1.add(textFieldUserName, new GridConstraints(0, 1, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_HORIZONTAL,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- labelPass ----
            labelPass.setText("\u5bc6   \u7801 \uff1a");
            labelPass.setFont(labelPass.getFont().deriveFont(labelPass.getFont().getStyle() | Font.BOLD, labelPass.getFont().getSize() + 3f));
            panel1.add(labelPass, new GridConstraints(1, 0, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_NONE,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));

            //---- passwordFieldPass ----
            passwordFieldPass.setFont(passwordFieldPass.getFont().deriveFont(passwordFieldPass.getFont().getSize() + 3f));
            panel1.add(passwordFieldPass, new GridConstraints(1, 1, 1, 1,
                GridConstraints.ANCHOR_CENTER, GridConstraints.FILL_HORIZONTAL,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
                null, null, null));
        }
        contentPane.add(panel1, new GridConstraints(0, 0, 1, 1,
            GridConstraints.ANCHOR_SOUTH, GridConstraints.FILL_HORIZONTAL,
            GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
            GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
            null, null, null));

        //---- buttonLogin ----
        buttonLogin.setText("\u767b \u5f55");
        buttonLogin.setVerticalTextPosition(SwingConstants.TOP);
        buttonLogin.setFont(buttonLogin.getFont().deriveFont(buttonLogin.getFont().getStyle() | Font.BOLD, buttonLogin.getFont().getSize() + 3f));
        buttonLogin.addActionListener(e -> {
            button2ActionPerformed(e);
            buttonLoginActionPerformed(e);
        });
        contentPane.add(buttonLogin, new GridConstraints(1, 0, 1, 1,
            GridConstraints.ANCHOR_NORTH, GridConstraints.FILL_NONE,
            GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
            GridConstraints.SIZEPOLICY_CAN_SHRINK | GridConstraints.SIZEPOLICY_CAN_GROW,
            null, null, null));
        pack();
        setLocationRelativeTo(getOwner());

        //---- optionPaneok ----
        optionPaneok.setIcon(UIManager.getIcon("OptionPane.informationIcon"));
        optionPaneok.setMessageType(JOptionPane.INFORMATION_MESSAGE);

        //---- optionPanefail ----
        optionPanefail.setIcon(UIManager.getIcon("OptionPane.errorIcon"));
        optionPanefail.setMessageType(JOptionPane.ERROR_MESSAGE);
        // JFormDesigner - End of component initialization  //GEN-END:initComponents
    }

    // JFormDesigner - Variables declaration - DO NOT MODIFY  //GEN-BEGIN:variables
    private JPanel panel1;
    private JLabel labelUser;
    private JTextField textFieldUserName;
    private JLabel labelPass;
    private JPasswordField passwordFieldPass;
    private JButton buttonLogin;
    private JOptionPane optionPaneok;
    private JOptionPane optionPanefail;
    // JFormDesigner - End of variables declaration  //GEN-END:variables
}

运行效果

hxfiowork.gif

This blog is under a CC BY-NC-ND 4.0 Unported License
本文链接:https://coding.emptinessboy.com/2020/05/%E5%87%A0%E4%B8%AA%E7%AE%80%E5%8D%95%E7%9A%84JAVA-GUI%E7%BB%83%E4%B9%A0/