GUI编程

组件

• 窗口
• 弹窗
• 面板
• 文本框
• 列表框
• 按钮
• 图片
• 监听事件
• 鼠标事件
• 键盘事件

简介

Gui核心技术： Swing、AWT

被逐渐淘汰原因：

1. 界面不美观
2. 需要jre环境

AWT

AWT（抽象窗口工具）介绍

1. 包含很多类和接口
2. 元素：窗口、按钮、文本框
3. java.awt

Frame图像窗口界面

public class TestFrame {
    public static void main(String[] args) {
        //窗口
        Frame frame = new Frame("java图形界面窗口");
        //设置可见性
        frame.setVisible(true);
        //设置窗口大小
        frame.setSize(400,400);
        //设置背景颜色
        frame.setBackground(new Color(1,1,1));
        //弹出的初始位置
        frame.setLocation(200,200);
        //设置大小固定(窗口大小不可拉伸)
        frame.setResizable(false);
    }
}

Frame图像窗口自定义封装

public class TestFrame2 {
    public static void main(String[] args) {
        MyFrame myFrame1 = new MyFrame(100,100,200,200,Color.red);
        MyFrame myFrame2 = new MyFrame(300,300,200,200,Color.yellow);
        MyFrame myFrame3 = new MyFrame(500,500,200,200,Color.blue);
    }
}

class MyFrame extends Frame {
    static int id = 0;  //计数器，可能存在多个窗口

    public MyFrame(int x, int y, int w, int h, Color color) {
        super("MyFrame"+(++id));
        setVisible(true);
        //设置屏幕位置和宽高
        setBounds(x,y,w,h);
        setBackground(color);
    }
}

Panel面板

public class TestPanel {
    public static void main(String[] args) {
        Frame frame = new Frame("Test");
        //面板
        Panel panel = new Panel();
        //设置布局
        frame.setLayout(null);
        frame.setBounds(300,300,500,500);
        frame.setBackground(new Color(1,1,1));
        //panel的坐标相对于frame
        panel.setBounds(50,50,400,400);
        panel.setBackground(new Color(255, 0, 4));
        //将panel放入frame
        frame.add(panel);
        frame.setVisible(true);

        //监听窗口关闭事件
        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                //结束程序
                System.exit(0);
            }
        });
    }
}

三种布局管理器

• 流式布局FlowLayout

public class TestFlowLayout {
    public static void main(String[] args) {
        Frame frame = new Frame();
        //按钮组件
        Button button1 = new Button("button1");
        Button button2 = new Button("button2");
        Button button3 = new Button("button3");
        //设置为流式布局
        //frame.setLayout(new FlowLayout()); 默认居中
        //frame.setLayout(new FlowLayout(FlowLayout.LEFT));  靠左
        frame.setLayout(new FlowLayout(FlowLayout.RIGHT));  //靠右
        frame.setSize(400,400);
        frame.setVisible(true);
        frame.add(button1);
        frame.add(button2);
        frame.add(button3);
    }
}

• 东西南北中BorderLayout

public class TestBorderLayout {
    public static void main(String[] args) {
        Frame frame = new Frame("TestBorderLayout");
        frame.setVisible(true);
        frame.setBounds(200,200,400,400);

        Button east = new Button("east");
        Button west = new Button("west");
        Button south = new Button("south");
        Button north = new Button("north");
        Button center = new Button("center");

        frame.add(east,BorderLayout.EAST);
        frame.add(west,BorderLayout.WEST);
        frame.add(south,BorderLayout.SOUTH);
        frame.add(north,BorderLayout.NORTH);
        frame.add(center,BorderLayout.CENTER);
    }
}

• 表格布局GridLayout

public class TestGridLayout {
    public static void main(String[] args) {
        Frame frame = new Frame("GridLayout");
        frame.setVisible(true);
        frame.setBounds(200,200,500,500);

        Button btn1 = new Button("btn1");
        Button btn2 = new Button("btn2");
        Button btn3 = new Button("btn3");
        Button btn4 = new Button("btn4");
        Button btn5 = new Button("btn5");
        Button btn6 = new Button("btn6");

        frame.setLayout(new GridLayout(3,2));

        frame.add(btn1);
        frame.add(btn2);
        frame.add(btn3);
        frame.add(btn4);
        frame.add(btn5);
        frame.add(btn6);
        
        //frame.pack();//自动布局
    }
}

练习

public class TestDemo {
    public static void main(String[] args) {
        Frame frame = new Frame("test");
        frame.setBounds(200,200,400,250);
        frame.setVisible(true);
        frame.setLayout(new GridLayout(2,1));

        Panel p1 = new Panel(new BorderLayout());
        Panel p2 = new Panel(new GridLayout(2,1));
        Panel p3 = new Panel(new BorderLayout());
        Panel p4 = new Panel(new GridLayout(2,2));

        p1.add(new Button("west-1"),BorderLayout.WEST);
        p1.add(new Button("east-1"),BorderLayout.EAST);
        p2.add(new Button("p2-btn-1"));
        p2.add(new Button("p2-btn-2"));
        p1.add(p2,BorderLayout.CENTER);

        p3.add(new Button("west-2"),BorderLayout.WEST);
        p3.add(new Button("east-2"),BorderLayout.EAST);
        p4.add(new Button("p4-btn-1"));
        p4.add(new Button("p4-btn-2"));
        p4.add(new Button("p4-btn-3"));
        p4.add(new Button("p4-btn-4"));
        p3.add(p4,BorderLayout.CENTER);

        frame.add(p1);
        frame.add(p3);
        
        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
    }
}

总结

1. Frame是一个顶级窗口
2. Panel无法单独显示，必须添加到某个容器中
3. 布局管理器
   1. 流式
   2. 东西南北中
   3. 表格
4. 大小、定位、背景颜色、可见性、监听

事件监听

按钮事件监听

public class ListenerTest {
    public static void main(String[] args) {
        Frame frame = new Frame("事件监听");
        frame.setBounds(200,200,200,200);
        frame.setVisible(true);

        Button btn = new Button("button");

        //按钮事件监听
        btn.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent actionEvent) {
                System.out.println("按下按钮");
            }
        });
        frame.add(btn);
        windowClosing(frame);
    }

    //关闭窗口事件
    public static void windowClosing(Frame frame){
        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
    }
}

共用一个监听事件

public class ListenerTest {
    public static void main(String[] args) {
        Frame frame = new Frame("test");
        Button btn1 = new Button("start");
        Button btn2 = new Button("stop");

        //可以显示定义命令，没有就是默认值
        btn2.setActionCommand("exit");

        MyMonitor monitor = new MyMonitor();
        btn1.addActionListener(monitor);
        btn2.addActionListener(monitor);

        frame.add(btn1,BorderLayout.NORTH);
        frame.add(btn2,BorderLayout.SOUTH);
        frame.setVisible(true);
        frame.setBounds(200,200,200,200);
        windowClosing(frame);
    }

    //关闭窗口事件
    public static void windowClosing(Frame frame){
        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
    }
}

class MyMonitor implements ActionListener{
    @Override
    public void actionPerformed(ActionEvent actionEvent) {
        //actionEvent.getActionCommand() 获得按钮信息
        System.out.println("getActionCommand():"+actionEvent.getActionCommand());
    }
}

输入框监听

public class Text {
    public static void main(String[] args) {
        //启动
        new MyFrame();
    }
}

class MyFrame extends Frame {
    public MyFrame() {
        TextField textField = new TextField();
        add(textField);

        //监听文本框文字
        textField.addActionListener(new MyActionListener());

        //设置替换编码
        textField.setEchoChar('*');

        setVisible(true);
        setBounds(200, 200, 400, 250);
        pack();
    }
}

class MyActionListener implements ActionListener {
    @Override
    public void actionPerformed(ActionEvent actionEvent) {
        TextField field = (TextField) actionEvent.getSource();//返回一个对象
        System.out.println(field.getText());//获取输入的文本
        field.setText("");//将文本框内容设置为空
    }
}

计算器实现

public class Cal {
    public static void main(String[] args) {
        new Calculator();
    }
}

//计算器类
class Calculator extends Frame {

    private TextField num1;
    private TextField num2;
    private TextField num3;

    public Calculator() {
        loadFrame();
    }

    public void loadFrame() {
        //组件
        num1 = new TextField(10);
        num2 = new TextField(10);
        num3 = new TextField(20);
        Button button = new Button("=");
        Label label = new Label("+");

        //监听器
        button.addActionListener(new MyCalListener());

        //布局
        setLayout(new FlowLayout());
        add(num1);
        add(label);
        add(num2);
        add(button);
        add(num3);

        //窗口
        setTitle("计算器");
        pack();
        setVisible(true);
        closingWindow();
    }

    public void closingWindow() {
        addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
    }

    //监听器类
    class MyCalListener implements ActionListener {
        @Override
        public void actionPerformed(ActionEvent actionEvent) {
            int n1 = Integer.parseInt(num1.getText());
            int n2 = Integer.parseInt(num2.getText());
            num3.setText(n1+n2+"");
            num1.setText("");
            num2.setText("");
        }
    }
}

画笔

public class TestPaint {
    public static void main(String[] args) {
        new MyPaint().loadFrame();
    }
}

class MyPaint extends Frame {

    public void loadFrame() {
        setVisible(true);
        setBounds(200,200,800,600);
        closingWindow();
    }

    public void closingWindow(){
        addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
    }

    //画笔
    @Override
    public void paint(Graphics g) {
        //画笔需要有颜色
        g.setColor(Color.red);
        g.drawOval(100,100,100,100);
        g.fillOval(100,300,100,100);

        g.setColor(Color.green);
        g.fillRect(300,100,100,100);
    }
}

鼠标监听

public class TestMouseListener {
    public static void main(String[] args) {
        new MyFrame("画图");
    }
}

class MyFrame extends Frame {

    private ArrayList points;

    public MyFrame(String title) {
        super(title);
        setBounds(200, 200, 400, 300);
        setVisible(true);
        //存放鼠标点击的点
        points = new ArrayList<>();
        //添加鼠标监听器
        addMouseListener(new MyMouseListener());
    }

    @Override
    public void paint(Graphics g) {
        Iterator iterator = points.iterator();
        while (iterator.hasNext()) {
            Point point = (Point) iterator.next();
            g.setColor(Color.red);
            g.fillOval(point.x, point.y, 10, 10);
        }
    }

    private class MyMouseListener extends MouseAdapter {
        @Override
        public void mousePressed(MouseEvent e) {
            points.add(new Point(e.getX(),e.getY()));
            MyFrame myFrame = (MyFrame) e.getSource();
            myFrame.repaint();
        }
    }
}

键盘监听

public class TestKeyListener {
    public static void main(String[] args) {
        new KeyFrame();
    }
}

class KeyFrame extends Frame {
    public KeyFrame() {
        setVisible(true);
        setBounds(200, 200, 400, 200);

        addKeyListener(new KeyAdapter() {
            @Override
            public void keyPressed(KeyEvent e) {
                //获得键盘按下的键
                int keyCode = e.getKeyCode();
                if (keyCode == KeyEvent.VK_UP) {
                    System.out.println("按下上键");
                }
            }
        });
    }
}

窗口监听

public class TestWindow {
    public static void main(String[] args) {
        new WindowFrame();
    }
}

class WindowFrame extends Frame {
    public WindowFrame() {
        setVisible(true);
        setBounds(200, 200, 400, 200);
        setBackground(Color.blue);

        addWindowListener(new WindowAdapter() {
            //关闭窗口
            @Override
            public void windowClosing(WindowEvent e) {
                System.out.println("windowClosing");
                System.exit(0);
            }

            //激活窗口
            @Override
            public void windowActivated(WindowEvent e) {
                System.out.println("windowActivated");
                WindowFrame source = (WindowFrame) e.getSource();
                source.setTitle("激活");
            }
        });
    }
}