4.JPanel面板和JScroll

JPanel

public class JPanelDemo extends JFrame {
    public JPanelDemo()  {
        Container container = this.getContentPane();
        container.setLayout(new GridLayout(2,1,10,10));     //后兩個參數的意思是，間距

        JPanel panel1=new JPanel(new GridLayout(1,3));
        JPanel panel2=new JPanel(new GridLayout(1,2));
        JPanel panel3=new JPanel(new GridLayout(1,4));
        panel1.add(new JButton("1"));
        panel1.add(new JButton("1"));
        panel1.add(new JButton("1"));
        panel2.add(new JButton("2"));
        panel2.add(new JButton("2"));
        panel3.add(new JButton("3"));
        panel3.add(new JButton("3"));
        panel3.add(new JButton("3"));
        panel3.add(new JButton("3"));

        container.add(panel1);
        container.add(panel2);
        container.add(panel3);

        this.setVisible(true);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        this.setSize(500,500);

    }

    public static void main(String[] args) {

new JPanelDemo();
    }
}

產生效果：

JScroll滾動條

public class JScrollDemo extends JFrame {
    public JScrollDemo() {
        Container container = this.getContentPane();
        //文本域
       JTextArea textArea = new JTextArea();
        textArea.setText("歡迎學習Java");
      // container.add(textArea);  用普通面板不行
     //改用Scroll面板
        JScrollPane scrollPane = new JScrollPane(textArea);
        container.add(scrollPane);

        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        setVisible(true);
        setBounds(100,100,300,350);
    }
    public static void main(String[] args) {
new JScrollDemo();
    }
}

5.按鈕

圖片按鈕

public class JButtonDemo01 extends JFrame {
    public JButtonDemo01() {
        Container container = this.getContentPane();
        //將圖片變成圖標
        URL resource = JButtonDemo01.class.getResource("aaa.jpg");
        ImageIcon icon = new ImageIcon(resource);

        //把這個圖標放在按鈕上
        JButton button = new JButton();
        button.setIcon(icon);
        button.setToolTipText("圖片按鈕");  //提示文本

        //add
        container.add(button);
        
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        setVisible(true);
        setSize(100,200);
    }
    public static void main(String[] args) {
new JButtonDemo01();
    }
}

單選框

public class JButtonDemo02 extends JFrame {
    public JButtonDemo02() {
        Container container = this.getContentPane();

       //單選框
        JRadioButton radioButton1 = new JRadioButton("JRadioButton1");
        JRadioButton radioButton2 = new JRadioButton("JRadioButton2");
        JRadioButton radioButton3 = new JRadioButton("JRadioButton3");

        //由于單選框只能選擇一個，需要分組,一個組里只能選一個
        ButtonGroup group = new ButtonGroup();
group.add(radioButton1);
group.add(radioButton2);
group.add(radioButton3);

        //add
        container.add(radioButton1,BorderLayout.CENTER);
        container.add(radioButton2,BorderLayout.NORTH);
        container.add(radioButton3,BorderLayout.SOUTH);

        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        setVisible(true);
        setSize(100,200);
    }
    public static void main(String[] args) {
        new JButtonDemo02();
    }
}

多選框

public class JButtonDemo03 extends JFrame{
    public JButtonDemo03() {
        Container container = this.getContentPane();
        //單選框
        JCheckBox box01 = new JCheckBox("checkBox01");
        JCheckBox box02 = new JCheckBox("checkBox02");
        //add
        container.add(box01,BorderLayout.CENTER);
        container.add(box02,BorderLayout.NORTH);

        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        setVisible(true);
        setSize(100,200);
    }
    public static void main(String[] args) {
        new JButtonDemo03();
    }

}

6.列表和下拉框

分類

• 下拉框

public class TestComboboxDemo extends JFrame {
    public TestComboboxDemo(){
        Container container = this.getContentPane();
        JComboBox status = new JComboBox();

        status.addItem(null);
        status.addItem("正在熱映");
        status.addItem("已下架");
        status.addItem("即將上映");
       
container.add(status);

        setSize(500,350);
        setVisible(true);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }

    public static void main(String[] args) {
        new TestComboboxDemo();
    }
}

• 列表

public class TestComboboxDemo02 extends JFrame{
    public TestComboboxDemo02(){
        Container container = this.getContentPane();
        //生成列表的內容
        //String[] contents={"1","2","3"};   靜態
        Vector contents = new Vector();           //動態
        //列表中需要放入內容
        JList list = new JList(contents);
contents.add("zhangsan");
contents.add("lisi");
contents.add("wangwu");

        container.add(list);

        setSize(500,350);
        setVisible(true);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }
    public static void main(String[] args) {
        new TestComboboxDemo02();
    }
}

應用

• 下拉框：選擇地區，或者一些單個選項（選項2個時用單選框，大于2個用下拉框，節省資源）
• 列表：展示一些信息，一般是動態擴容

7.文本框

• 文本框TextField

public class TextTextDemo01 extends JFrame{
    public TextTextDemo01(){
        Container container = this.getContentPane();
//文本框
        JTextField textField = new JTextField("Hello");
        JTextField textField2= new JTextField("World",20);

        container.add(textField,BorderLayout.SOUTH);
        container.add(textField2,BorderLayout.NORTH);   //布局時如果元件數量太多，用絕對布局
        
        setSize(500,350);
        setVisible(true);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }
    public static void main(String[] args) {
        new TextTextDemo01();
    }
}

• 密碼框PasswordField

//密碼框
        JPasswordField passwordField = new JPasswordField();  //******
        passwordField.setEchoChar('*');

        container.add(passwordField);

• 文本域 TextArea
  代碼見Scroll部分

//文本域
       JTextArea textArea = new JTextArea();
        textArea.setText("歡迎學習Java");