JAVA学习-GUI编程之AWT

2021-11-16 09:11:44

GUI编程之AWT

Frame

写一个属于自己的第一个窗口

package com.frame.myFirstFrame;

import java.awt.*;

public class FirstFrame01 {
    public static void main(String[] args) {
        Frame frame = new Frame("我的第一个窗口！"); //构造器里是窗口title
        frame.setVisible(true); //窗口可视化
        frame.setSize(200,200); //窗口大小
        frame.setBackground(Color.GRAY);//窗口背景颜色
        frame.setLocation(100,100);//窗口位置
        frame.setResizable(false);//窗口是否可调节大写
    }
}

封装实现多窗口

package com.frame.myFirstFrame;

import java.awt.*;

public class Frame02 extends Frame { //继承Frame
    static int count = 0;
    public Frame02(int w, int h, int x, int y, Color color){ //有参构造器里面去封装
        super("我的第"+(++count)); //重写父类的构造器
        setBackground(color); //调用父类方法，不用加类名
        setResizable(false);
        setBounds(x,y,w,h);//这个方法直接包含长宽高
        setVisible(true);
    }
}
////////////////////////////////////////
package com.frame.myFirstFrame;

import java.awt.*;

public class Application {
    public static void main(String[] args) {
        new Frame02(200,200,100,100, Color.black);
        new Frame02(200,200,300,100, Color.white);
        new Frame02(200,200,100,300, Color.yellow);
        new Frame02(200,200,300,300, Color.blue);
    }
}

Panel

基于上面的窗口，加入面板

package com.frame.myFirstFrame;

import java.awt.*;

public class Application {
    public static void main(String[] args) {
        Frame02 f1 = new Frame02(200, 200, 100, 100, Color.black);
        Frame02 f2 = new Frame02(200, 200, 300, 100, Color.white);
        Frame02 f3 = new Frame02(200, 200, 100, 300, Color.yellow);
        Frame02 f4 = new Frame02(200, 200, 300, 300, Color.blue);
        Panel panel = new Panel();
        panel.setBackground(new Color(158, 160, 156));
        panel.setBounds(20,100,60,60);
        f1.add(panel);//.add()放入的是一个component panel是component的子类，所以可以放进去
    }
}

//添加监听，可以关闭窗口
//适配器模式
f1.addWindowListener(new WindowAdapter() {
   @Override
   public void windowClosing(WindowEvent e) {
           System.exit(0);//结束程序
    }
});

布局管理器

流式布局
东西南北中
表格布局

frame.setLayout(new FlowLayout());//设置为流式布局
//流式布局三种:CENTER LEFT RIGHT
//默认为CENTER
//这样就设置成左了
frame.setLayout(new Flowlayout(FlowLayout.LEFT));

frame.add(east,BorderLayout.East);//把east按钮放在东边
//这里因为不会自动填充，所以需要每个按钮去设置他的布局

frame.setLayout(new GridLayout(3,2));//表格布局，三行两列

做一个作业：设置为如下布局：

package com.frame.myFirstFrame;

import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

public class FlowLayout {
    public static void main(String[] args) {
        Frame frame = new Frame("作业布局");
        frame.setVisible(true);
        frame.setBounds(100,100,500,500);
        frame.setBackground(new Color(26, 124, 124));
        frame.setLayout(new GridLayout(2,1));//先分成两行一列，放面板
        //四个面板
        Panel p1 = new Panel(new BorderLayout());
        Panel p2 = new Panel(new BorderLayout());
        Panel p3 = new Panel(new GridLayout(2,1));
        Panel p4 = new Panel(new GridLayout(2,2));
        ///上面的处理
        p1.add(new Button("p1-east"),BorderLayout.EAST);
        p1.add(new Button("p1-west"),BorderLayout.WEST);
        p3.add(new Button("p1-p3-center1"));
        p3.add(new Button("p1-p3-center2"));
        p1.add(p3,BorderLayout.CENTER);
        ///下面的处理
        p2.add(new Button("p2-east"),BorderLayout.EAST);
        p2.add(new Button("p2-west"),BorderLayout.WEST);
        for (int i = 0; i < 4; i++) {
            p4.add(new Button("p2-p4-center"+(++i)));
        }
        p2.add(p4);
        frame.add(p1);
        frame.add(p2);
        //监听 关闭
        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
    }
}

运行结果：

事件监听

package com.frame.myFirstFrame;

import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

public class Application {
    public static void main(String[] args) {
        Frame frame = new Frame("start-stop");
        frame.setBounds(100,100,500,500);
        frame.setVisible(true);
        Button b1 = new Button("start");
        Button b2 = new Button("stop");
        //b1.setActionCommand("1");
        //b2.setActionCommand("2");
        //这两行是setActionCommand
        frame.setLayout(new GridLayout(2,1));
        frame.add(b1);
        frame.add(b2);
        MonitorAction monitorAction = new MonitorAction();
        b1.addActionListener(monitorAction);//要用addActionListener就必须要去实现接口ActionListener的方法
        b2.addActionListener(monitorAction);
    }
}
//////////////
package com.frame.myFirstFrame;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class MonitorAction implements ActionListener {
    @Override
    public void actionPerformed(ActionEvent e) {
        String actionCommand = e.getActionCommand();//如果没有setActionCommand，则e中存放的是Button的label
        if (actionCommand.equals("start")){
            System.out.println("监听开始！");
        }
        if (actionCommand.equals("stop")){
            System.exit(0);
        }
    }
}

输入框事件监听

输入框：TextField

输入框中按下enter 就会触发这个输入框事件

package com.frame.myFirstFrame;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class MyTextField {
    public static void main(String[] args) {
        new MyFrame();
    }
}
class MyFrame extends Frame{
    public MyFrame() throws HeadlessException {
        setBackground(Color.GRAY);
        setVisible(true);
        TextField textField = new TextField();
        Panel p1 = new Panel();
        add(p1);
        p1.add(textField);
        MyTextMontor myTextMontor = new MyTextMontor();
        textField.addActionListener(myTextMontor);
        //设置为替换编码，密码输入常用
        textField.setEchoChar('*');
    }
}
class MyTextMontor implements ActionListener{
    @Override
    public void actionPerformed(ActionEvent e) {
        TextField getSource = (TextField) e.getSource();//e.getSource是获得一些资源，返回对象 这里强转为TxetField类方便下一步利用TextField的方法
        System.out.println(getSource.getText());//.getText()是TextField的方法，可以得到文本框中的内容并Return为String类,然后传送到后台
    }
}

一个简易的计算器

实现在文本框填写两个数字，点击 = 即可得到答案并且清空文本框

最初代码：

package com.frame.myFirstFrame;

import java.awt.*;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class Calculator {
    public static void main(String[] args) {
        new MyCalculator();
    }
}
class MyCalculator extends Frame{
    public MyCalculator() {
        setVisible(true);
        setBounds(100,100,300,300);
        pack();
        //文本框
        TextField num1 = new TextField(10);//columns 文本框的长度
        TextField num2 = new TextField(10);
        TextField num3 = new TextField(11);
        //标签类 用来放 +
        Label label = new Label("+");
        //按钮
        Button button = new Button("=");
        //把上面放进去
        setLayout(new FlowLayout());
        add(num1);
        add(label);
        add(num2);
        add(button);
        add(num3);
        //写监听
        MyCalcMontor myCalcMontor = new MyCalcMontor(num1, num2,num3);
        button.addActionListener(myCalcMontor);
    }
}
class MyCalcMontor implements ActionListener{
    public TextField num0;
    public TextField num1;
    public TextField num3;
    public MyCalcMontor(TextField num1, TextField num2, TextField num3) {
         this.num0 = num1;
         this.num1 = num2;
         this.num3 = num3;
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        int a = Integer.parseInt(this.num0.getText());//使用Integer的parseInt方法，将String转换为int
        int b = Integer.parseInt(this.num1.getText());
        num3.setText(""+(a+b)); //这里个人理解为什么在这里可以影响到框内的内容：原因是因为TextField这类的赋值，会把权限也赋予出去，也就是对那个框的权限赋予给了this.num0 this.num1 this.num3
        num0.setText("");
        num1.setText("");
    }
}

优化代码，利用组合的方法：

package com.frame.myFirstFrame;

import java.awt.*;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class CalDemo01 {
    public static void main(String[] args) {
        new MyNewCal().LoadFrame();

    }
}
class MyNewCal extends Frame {
    TextField num1,num2,num3; //TextField是一个class 使用就要new
    public void LoadFrame(){
        num1 = new TextField(10);
        num2 = new TextField(10);
        num3 = new TextField(20);
        Button button = new Button("=");
        Label label = new Label("+");

        setVisible(true);
        setBounds(100,100,400,400);
        pack();
        setLayout(new FlowLayout());
        add(num1);
        add(label);
        add(num2);
        add(button);
        add(num3);

        MyNewMontor myNewMontor = new MyNewMontor(this);//把类丢进监控器类里面用
        button.addActionListener(myNewMontor);

    }

}
class MyNewMontor implements ActionListener {
    MyNewCal myNewCal = null;//组合 

    public MyNewMontor(MyNewCal myNewCal) { //把类丢进来，就可以直接用这个类的所有东西
        this.myNewCal = myNewCal;
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        int a = Integer.parseInt(myNewCal.num1.getText());
        int b = Integer.parseInt((myNewCal.num2.getText()));
        myNewCal.num3.setText(""+(a+b));
        myNewCal.num1.setText("");
        myNewCal.num2.setText("");

    }
}

继续优化，利用内部类：

package com.frame.myFirstFrame;

import java.awt.*;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class CalDemo01 {
    public static void main(String[] args) {
        new MyNewCal().LoadFrame();

    }
}
class MyNewCal extends Frame {
    TextField num1,num2,num3;
    public void LoadFrame(){
        num1 = new TextField(10);
        num2 = new TextField(10);
        num3 = new TextField(20);
        Button button = new Button("=");
        Label label = new Label("+");

        setVisible(true);
        setBounds(100,100,400,400);
        pack();
        setLayout(new FlowLayout());
        add(num1);
        add(label);
        add(num2);
        add(button);
        add(num3);


        button.addActionListener(new MyNewMontor());

    }
    private class  MyNewMontor implements ActionListener { //内部类，可以直接调用外部类所有东西，不用再组合，也不用构造器传参

        @Override
        public void actionPerformed(ActionEvent e) {
            int a = Integer.parseInt(num1.getText());
            int b = Integer.parseInt((num2.getText()));
            num3.setText(""+(a+b));
            num1.setText("");
            num2.setText("");

        }
    }
}

画笔

package com.frame.myFirstFrame;

import java.awt.*;

public class Paint {
    public static void main(String[] args) {
        new MyPaint().LoadFrame();//注意这里new的是LoadFrame

    }
}
class MyPaint extends Frame{
    public void LoadFrame(){ //这里要用这个方法才能让弹窗活下来
        setVisible(true);
        setBounds(100,100,400,400);
    }
    @Override
    public void paint(Graphics g) {

        g.setColor(Color.BLUE);
        g.fillOval(100,100,200,200);
    }
}

鼠标监听

package com.frame.myFrame;

import java.awt.*;
import java.awt.event.*;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.Vector;

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

}
class MyFrame extends Frame {
     ArrayList points;//一个集合，用于存放所有的鼠标点的点
    public MyFrame(String tittle) {
        super(tittle);
        points = new ArrayList(); //!!!!注意，这里要把实例化放在构造器里面，这样这个类就都可以用了！
    }
    public void LoadFrame(){

        setVisible(true);
        setBounds(100,100,400,400);
        this.addMouseListener(new MyMouseListener());
        addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
    }
    @Override
    public void paint(Graphics g) {
        Iterator iterator = points.iterator();
        while (iterator.hasNext()){
            Point point = (Point) iterator.next();//!!!注意，这里迭代器一定要指向下一个，也就是.next()必须要写！
            g.fillOval(point.x,point.y,10,10);
        }
    }
    public class MyMouseListener extends MouseAdapter { //MouseAdapter是一个适配器，帮我们完成了一些方法
        @Override
        public void mousePressed(MouseEvent e) { //这里的e存放了所有监听到的鼠标的内容
            //MyFrame frame = (MyFrame) e.getSource(); **这句话暂时不知道有什么意义，去掉不影响**
            addPoint(new Point(e.getPoint())); //存放到points集合 ！！内部类可以直接调用外部类所有的东西
            repaint();


        }
    }
    public void addPoint(Point point) {
        this.points.add(point);

    }
    
}

血的教训！！！

一定要注意实例化。要用一个类，那么这个类必须要实例化！把实例化放在构造器中，相当于放在类的属性里面，就在骨子里面完成了实例化！

窗口监听

package com.frame;

import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

public class WinListener {
    public static void main(String[] args) {
        new MyWindowListener().LoadFrame();

    }
}
class MyWindowListener extends Frame {
    public MyWindowListener() {

    }
    public void LoadFrame(){
        setBackground(Color.cyan);
        setBounds(100,100,400,400);
        setVisible(true);
        this.addWindowListener(new WindowAdapter() { //匿名内部类，更加方便简洁
            @Override
            public void windowClosing(WindowEvent e) { //关闭窗口监听
                System.out.println("你关闭了这个窗口！");
                System.exit(0);
            }

            @Override
            public void windowActivated(WindowEvent e) {//焦点监听
                MyWindowListener myWindowListener = (MyWindowListener) e.getSource();//e.getSource是获取资源，这里我们获取了窗口的所有资源，才能够改变窗口的title
                myWindowListener.setTitle("你回来了！");
            }

            @Override
            public void windowDeactivated(WindowEvent e) {//非焦点监听
                MyWindowListener myWindowListener = (MyWindowListener) e.getSource();
                myWindowListener.setTitle("你离开我了");
            }
        });
    }
}

键盘监听

大同小异，同上！

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