javaSE第二十五天

Posted 2020-08-09

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第二十五天????399

1:如何让Netbeans的东西Eclipse能访问。????399

A:javax.swing包下的方法????399

1. UserDao（顶层接口）????401

2. UserAdapter（适配器类，实现顶层接口）????401

3. UserDaoImpl（具体实现类，需继承UserAdapter适配器类）????402

(7)案例：????402

A:创建窗体案例????402

B:窗体关闭案例????403

C:窗体添加按钮并对按钮添加事件案例。????404

界面中的组件布局。????404

D:把文本框里面的数据转移到文本域????405

E:更改背景色????407

F:设置文本框里面不能输入非数字字符????409

G:一级菜单????410

H:多级菜单????411

(8)Netbeans的概述和使用????414

第二十五天

1:如何让Netbeans的东西Eclipse能访问。

????在Eclipse中创建项目，把Netbeans项目的src下的东西给拿过来即可。

????注意：修改项目编码为UTF-8

????

2:GUI(了解)

????(1)用户图形界面

????????GUI:方便直观

????????CLI:需要记忆一下命令，麻烦

????(2)两个包：

????????java.awt:和系统关联较强（重量级）

????????javax.swing:纯Java编写（轻量级）

????(3)主要方法：

????????A:javax.swing包下的方法????

????????????构造方法：

????????????public JFrame(String title)：创建对象的同时，设置标题名称

????????????public JFrame()：无参构造

????????????普通方法：

????????????public void setTitle(String title)：设置窗体的标题

????????????public void setSize(int width, int height)：设置窗体的大小

public void setSize(Dimension d)：通过传入Dimension对象设置窗体大小

????????????public Dimension(int width, int height)：Dimension类的构造方法

????????????public void setLocation(int x, int y)：设置窗体的坐标

public void setLocation(Point p)：通过传入一个Point对象，来设置窗体坐标

public Point(int x, int y)：Point类的构造方法

????????????public void setVisible(boolean b)：设置让窗体可见

????????????用一个方法完成窗体大小和坐标的设置

????????????public void setBounds(int x, int y, int width, int height)：

????????????参数x、y设置窗体坐标。Width、height设置窗体大小

????????????public void setLayout(LayoutManager mgr)：设置窗体的布局模式

????????????????????????常用的为流式布局：FlowLayout

????????B:监听机制的应用

????????????案例：关闭窗体

????????????

import java.awt.Frame;

import java.awt.event.WindowAdapter;

import java.awt.event.WindowEvent;

public?class FrameDemo {

????public?static?void main(String[] args) {

????????// 创建窗体对象

????????JFrame f = new JFrame("窗体关闭案例");

????????// 设置窗体属性

????????f.setBounds(400, 200, 400, 300);

????????//用适配器类改进

????????f.addWindowListener(new?WindowAdapter() {

????????????@Override

????????????public?void?windowClosing(WindowEvent e) {

????????????????System.exit(0);

????????????}

????????});

????????// 设置窗体可见

????????f.setVisible(true);

????}

}

????(4)GUI的继承体系

????????组件：组件就是对象

????????????容器组件：是可以存储基本组件和容器组件的组件。

????????????基本组件：是可以使用的组件，但是必须依赖容器。

????(5)事件监听机制(理解)

????????A:事件源

????????B:事件

????????C:事件处理

????????D:事件监听

????(6)适配器模式(理解)

????????应用场景：当一个接口中有蛮多方法的时候，而我们只需要用其中某一个方法，但是呢？

????????????????用其中的一个方法，就要实现该接口中的所有方法，有点不划算，所以呢？

????????????????适配器模式就应运而生啦

????????A:接口

????????????????定义一个顶层的接口

????????B:抽象适配器类

????????????????用一个抽象类实现该接口，当然是空实现（不提供具体的方法体）

????????C:实现类

????????????用具体的类继承抽象适配器类，想用哪个方法，就重写哪个方法，不用重写所有方法

????????案例解释

????????????1. UserDao（顶层接口）

* 顶层接口：针对用户操作的四种功能

public?interface UserDao {

????public?abstract?void add();

????public?abstract?void delete();

????public?abstract?void update();

????public?abstract?void find();

}

????????????2. UserAdapter（适配器类，实现顶层接口）

* 定义一个类实现UserDao接口：当然啦，是空实现

public?abstract?class UserAdapter implements UserDao {

????@Override

????public?void add() {

????}

????@Override

????public?void delete() {

????}

????@Override

????public?void update() {

????}

????@Override

????public?void find() {

????}

}

????????????3. UserDaoImpl（具体实现类，需继承UserAdapter适配器类）

* 具体实现类：继承UserAdapter适配器类，重写里面

* ????????????自己想要使用的方法

public?class UserDaoImpl extends UserAdapter {

????@Override

????public?void add() {

????????System.out.println("添加功能");

????}

}

????????????4. UserDaoDemo（测试类）

* 问题：

* ????????接口(方法比较多) -- 实现类(仅仅使用一个，也得把其他的实现给提供了，哪怕是空实现)

* ????????太麻烦了。

* 解决方案：

* ????????接口(方法比较多) -- 适配器类(实现接口,仅仅空实现) -- 实现类(用哪个重写哪个)

public?class UserDaoDemo {

????public?static?void main(String[] args) {

????????UserDao ud = new UserDaoImpl();

????????ud.add();

????????// 我没有说我们需要四种功能都实现啊。

????????UserDao ud2 = new UserDaoImpl2();

????????ud2.add();

????}

}

????

????(7)案例：

????????A:创建窗体案例

import javax.swing.JFrame;

* 需求：创建一个窗体（该窗体默认情况下是不能关闭的）

public?class FrameDemo {

????public?static?void main(String[] args) {

????????// 创建窗体对象

????????// Frame f = new Frame();

????????// Frame(String title)

????????JFrame f = new JFrame("林青霞");

????????// 设置窗体标题

????????f.setTitle("HelloWorld");

????????// 设置窗体大小

????????f.setSize(400, 300); // 单位：像素

????????// 设置窗体位置

????????f.setLocation(400, 200);

????????// 调用一个方法，设置让窗体可见

????????// f.show();

????????f.setVisible(true);

????????// System.out.println("helloworld");

????}

}

????????B:窗体关闭案例

????????

import java.awt.event.WindowAdapter;

import java.awt.event.WindowEvent;

import javax.swing.JFrame;

* 需求：创建一个窗体（该窗体可以直接被关闭的）

public?class FrameDemo {

????public?static?void main(String[] args) {

????????// 创建窗体对象

????????JFrame f = new JFrame("窗体关闭案例");

????????// 设置窗体属性

????????f.setBounds(400, 200, 400, 300);

????????

????????//用适配器类改进，为窗体添加监听机制

????????f.addWindowListener(new WindowAdapter() {

????????????@Override

????????????public?void windowClosing(WindowEvent e) {

????????????????System.exit(0);

????????????}

????????});

????????// 设置窗体可见

????????f.setVisible(true);

????}

}

????????C:窗体添加按钮并对按钮添加事件案例。

????????????界面中的组件布局。

import java.awt.Button;

import java.awt.FlowLayout;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.event.WindowAdapter;

import java.awt.event.WindowEvent;

import?javax.swing.JFrame;

* 需求：把按钮添加到窗体，并对按钮添加一个点击事件。

* A：创建窗体对象

* B:创建按钮对象

* C:把按钮添加到窗体

* D:窗体显示

public?class FrameDemo {

????public?static?void main(String[] args) {

????????// 创建窗体对象

????????JFrame?f = new?JFrame("添加按钮");

????????// 设置属性

????????f.setBounds(400, 200, 400, 300);

????????// 设置布局为流式布局

????????f.setLayout(new FlowLayout());

????????// 创建按钮对象

????????Button bu = new Button("点我啊");

????????// bu.setSize(20, 10);

????????// 把按钮添加到窗体

????????f.add(bu);

????????// 设置窗体可以关闭

????????f.addWindowListener(new WindowAdapter() {

????????????@Override

????????????public?void windowClosing(WindowEvent e) {

????????????????System.exit(0);

????????????}

????????});

????????bu.addActionListener(new ActionListener() {

????????????@Override

????????????public?void actionPerformed(ActionEvent e) {

????????????????System.out.println("你再点试试");

????????????}

????????});

????????// 窗体显示

????????f.setVisible(true);

????}

}

????????D:把文本框里面的数据转移到文本域

import java.awt.Button;

import java.awt.FlowLayout;

import java.awt.TextArea;

import java.awt.TextField;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.event.WindowAdapter;

import java.awt.event.WindowEvent;

import javax.swing.JFrame;

* 需求：将文本框中的数据转移到文本域中

public?class FrameDemo {

????public?static?void main(String[] args) {

????????// 创建窗体对象

????????JFrame f = new JFrame("数据转移");

????????// 设置窗体属性和布局

????????f.setBounds(400, 200, 400, 300);

????????f.setLayout(new FlowLayout());

????????// 创建文本框

????????final TextField tf = new TextField(20);

????????// 创建按钮

????????Button bu = new Button("数据转移");

????????// 创建文本域

????????final TextArea ta = new TextArea(10, 40);

????????// 把组件添加到窗体

????????f.add(tf);

????????f.add(bu);

????????f.add(ta);

????????// 设置窗体关闭

????????f.addWindowListener(new WindowAdapter() {

????????????@Override

????????????public?void windowClosing(WindowEvent e) {

????????????????System.exit(0);

????????????}

????????});

????????// 对按钮添加事件

????????bu.addActionListener(new ActionListener() {

????????????@Override

????????????public?void actionPerformed(ActionEvent e) {

????????????????// 获取文本框的值

????????????????String tf_str = tf.getText().trim();

????????????????// 清空数据

????????????????tf.setText("");

????????????????// 设置给文本域

????????????????// ta.setText(tf_str);

????????????????// 追加和换行

????????????????ta.append(tf_str + "\r\n");

????????????????

????????????????//获取光标

????????????????tf.requestFocus();

????????????}

????????});

????????// 设置窗体显示

????????f.setVisible(true);

????}

}

????????E:更改背景色

import java.awt.Button;

import java.awt.Color;

import java.awt.FlowLayout;

import?java.awt.Frame;

import java.awt.event.MouseAdapter;

import java.awt.event.MouseEvent;

import java.awt.event.WindowAdapter;

import java.awt.event.WindowEvent;

* 需求：更改背景色

public?class FrameDemo {

????public?static?void main(String[] args) {

????????// 创建窗体对象，局部内部类访问局部变量，局部变量必须用final修饰

????????final?Frame?f = new?Frame("更改背景色");

????????// 设置窗体属性和布局

????????f.setBounds(400, 200, 400, 300);

????????f.setLayout(new FlowLayout());

????????// 创建四个按钮

????????Button redButton = new Button("红色");

????????Button greenButton = new Button("绿色");

????????Button buleButton = new Button("蓝色");

????????// 添加按钮

????????f.add(redButton);

????????f.add(greenButton);

????????f.add(buleButton);

????????// 设置窗体关闭

????????f.addWindowListener(new WindowAdapter() {

????????????@Override

????????????public?void windowClosing(WindowEvent e) {

????????????????System.exit(0);

????????????}

????????});

????????// 对按钮添加动作事件

????????// redButton.addActionListener(new ActionListener() {

????????// @Override

????????// public void actionPerformed(ActionEvent e) {

????????// f.setBackground(Color.RED);

????????// }

????????// });

????????// 对按钮添加鼠标点击事件

????????// redButton.addMouseListener(new MouseAdapter() {

????????// @Override

????????// public void mouseClicked(MouseEvent e) {

????????// f.setBackground(Color.RED);

????????// }

????????// });

????????// 对按钮添加鼠标的进入事件

????????redButton.addMouseListener(new MouseAdapter() {

????????????@Override

????????????public?void mouseEntered(MouseEvent e) {

????????????????f.setBackground(Color.RED);

????????????}

????????});

????????// 对按钮添加鼠标的离开事件

????????redButton.addMouseListener(new MouseAdapter() {

????????????@Override

????????????public?void mouseExited(MouseEvent e) {

????????????????f.setBackground(Color.WHITE);

????????????}

????????});

????????greenButton.addMouseListener(new MouseAdapter() {

????????????@Override

????????????public?void mouseEntered(MouseEvent e) {

????????????????f.setBackground(Color.GREEN);

????????????}

????????});

????????greenButton.addMouseListener(new MouseAdapter() {

????????????@Override

????????????public?void mouseExited(MouseEvent e) {

????????????????f.setBackground(Color.WHITE);

????????????}

????????});

????????buleButton.addMouseListener(new MouseAdapter() {

????????????@Override

????????????public?void mouseEntered(MouseEvent e) {

????????????????f.setBackground(Color.BLUE);

????????????}

????????});

????????buleButton.addMouseListener(new MouseAdapter() {

????????????@Override

????????????public?void mouseExited(MouseEvent e) {

????????????????f.setBackground(Color.WHITE);

????????????}

????????});

????????// 设置窗体显示

????????f.setVisible(true);

????}

}

????????F:设置文本框里面不能输入非数字字符

import java.awt.FlowLayout;

import?java.awt.Frame;

import java.awt.Label;

import java.awt.TextField;

import java.awt.event.KeyAdapter;

import java.awt.event.KeyEvent;

import java.awt.event.WindowAdapter;

import java.awt.event.WindowEvent;

* 需求：你输入的如果是非数字字符，就取消你键盘录入的效果。

public?class FrameDemo {

????public?static?void main(String[] args) {

????????// 创建窗体对象并设置属性

????????Frame?f = new?Frame("不能输入非数字字符");

????????f.setBounds(400, 200, 400, 300);

????????f.setLayout(new FlowLayout());

????????// 创建Label标签对象

????????Label label = new Label("请输入你的QQ号码，不能是非数字，不信你试试");

????????TextField tf = new TextField(40);

????????// 添加到窗体上

????????f.add(label);

????????f.add(tf);

????????// 设置窗体关闭

????????f.addWindowListener(new WindowAdapter() {

????????????@Override

????????????public?void windowClosing(WindowEvent e) {

????????????????System.exit(0);

????????????}

????????});

????????// 给文本框添加事件

????????tf.addKeyListener(new KeyAdapter() {

????????????@Override

????????????public?void keyPressed(KeyEvent e) {

????????????????// 如果你取得的字符不是数字字符就取消事件

????????????????// 思路：先获取字符，判断字符，取消事件

????????????????// char getKeyChar()

????????????????char?ch = e.getKeyChar();

????????????????// System.out.println(ch);

????????????????if (!(ch >= ‘0‘ && ch <= ‘9‘)) {

????????????????????e.consume();

????????????????}

????????????}

????????});

????????// 设置窗体可见

????????f.setVisible(true);

????}

}

????????G:一级菜单

import java.awt.FlowLayout;

import java.awt.Frame;

import java.awt.Menu;

import java.awt.MenuBar;

import java.awt.MenuItem;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.event.WindowAdapter;

import java.awt.event.WindowEvent;

* 需求：制作一级菜单

public?class FrameDemo {

????public?static?void main(String[] args) {

????????// 创建窗体对象并设置属性

????????Frame f = new Frame("一级菜单");

????????f.setBounds(400, 200, 400, 300);

????????f.setLayout(new FlowLayout());

????????// 创建菜单栏

????????MenuBar mb = new MenuBar();

????????// 创建菜单

????????Menu m = new Menu("文件");

????????// 创建菜单项

????????MenuItem mi = new MenuItem("退出系统");

????????// 谁添加谁呢

????????m.add(mi);

????????mb.add(m);

????????// 设置菜单栏

????????f.setMenuBar(mb);

????????// 设置窗体关闭

????????f.addWindowListener(new WindowAdapter() {

????????????@Override

????????????public?void windowClosing(WindowEvent e) {

????????????????System.exit(0);

????????????}

????????});

????????mi.addActionListener(new ActionListener() {

????????????@Override

????????????public?void actionPerformed(ActionEvent e) {

????????????????System.exit(0);

????????????}

????????});

????????// 设置窗体可见

????????f.setVisible(true);

????}

}

????????H:多级菜单

import java.awt.FlowLayout;

import java.awt.Frame;

import java.awt.Menu;

import java.awt.MenuBar;

import java.awt.MenuItem;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.event.WindowAdapter;

import java.awt.event.WindowEvent;

import java.io.IOException;

* 需求：制作多级菜单

public?class FrameDemo {

????public?static?void main(String[] args) {

????????// 创建窗体对象并设置属性

????????final Frame f = new Frame("多级菜单");

????????f.setBounds(400, 200, 400, 300);

????????f.setLayout(new FlowLayout());

????????

????????final String name = f.getTitle();

????????// 创建菜单栏

????????MenuBar mb = new MenuBar();

????????// 创建菜单

????????Menu m1 = new Menu("文件");

????????Menu m2 = new Menu("更改名称");

????????// 创建菜单项

????????final MenuItem mi1 = new MenuItem("好好学习");

????????final MenuItem mi2 = new MenuItem("天天向上");

????????MenuItem mi3 = new MenuItem("恢复标题");

????????MenuItem mi4 = new MenuItem("打开记事本");

????????MenuItem mi5 = new MenuItem("退出系统");

????????// 谁添加谁呢

????????m2.add(mi1);

????????m2.add(mi2);

????????m2.add(mi3);

????????

????????m1.add(m2);

????????m1.add(mi4);

????????m1.add(mi5);

????????

????????mb.add(m1);

????????// 设置菜单栏

????????f.setMenuBar(mb);

????????// 设置窗体关闭

????????f.addWindowListener(new WindowAdapter() {

????????????@Override

????????????public?void windowClosing(WindowEvent e) {

????????????????System.exit(0);

????????????}

????????});

????????

????????mi1.addActionListener(new ActionListener() {

????????????@Override

????????????public?void actionPerformed(ActionEvent e) {

????????????????f.setTitle(mi1.getLabel());

????????????}

????????});

????????

????????mi2.addActionListener(new ActionListener() {

????????????@Override

????????????public?void actionPerformed(ActionEvent e) {

????????????????f.setTitle(mi2.getLabel());

????????????}

????????});

????????

????????mi3.addActionListener(new ActionListener() {

????????????@Override

????????????public?void actionPerformed(ActionEvent e) {

????????????????f.setTitle(name);

????????????}

????????});

????????

????????mi4.addActionListener(new ActionListener() {

????????????@Override

????????????public?void actionPerformed(ActionEvent e) {

????????????????Runtime r = Runtime.getRuntime();

????????????????try {

????????????????????r.exec("notepad");

????????????????} catch (IOException e1) {

????????????????????e1.printStackTrace();

????????????????}

????????????}

????????});

????????mi5.addActionListener(new ActionListener() {

????????????@Override

????????????public?void actionPerformed(ActionEvent e) {

????????????????System.exit(0);

????????????}

????????});

????????// 设置窗体可见

????????f.setVisible(true);

????}

}

????(8)Netbeans的概述和使用

????????A:是可以做Java开发的另一个IDE工具，做GUI界面开发特别方便。

????????B:使用

????????????A:四则运算

????????????????a:修改图标????????b:设置皮肤

????????????????c:设置居中????????d:数据校验

????????????B:登录注册

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