java.awt.flowlayout
时间: 2023-04-16 16:03:22 浏览: 150
Java.awt.FlowLayout是Java中的一个布局管理器,它可以将组件按照一定的顺序排列在容器中。FlowLayout布局管理器会自动调整组件的位置和大小,以适应容器的大小和组件的数量。它的特点是组件按照从左到右、从上到下的顺序排列,如果容器的宽度不足以容纳所有组件,则会自动折行。FlowLayout布局管理器适用于需要按照一定顺序排列组件的情况,例如按钮、标签等。
相关问题
package work13; import javax.swing.*; import java.awt.*; import java.awt.event.ItemEvent; import java.awt.event.ItemListener; public class Jframe { JFrame f = new JFrame("窗口"); JTextArea ta = new JTextArea("测试用例", 10, 20); JComboBox<String>
box; String[] choices = {"选项1", "选项2", "选项3"}; public Jframe() { f.setLayout(new FlowLayout()); f.setSize(300, 300); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); box = new JComboBox<>(choices); box.addItemListener(new ItemListener() { @Override public void itemStateChanged(ItemEvent e) { if (e.getStateChange() == ItemEvent.SELECTED) { String choice = (String) box.getSelectedItem(); ta.setText(choice); } } }); f.add(box); f.add(ta); f.setVisible(true); } public static void main(String[] args) { new Jframe(); } }
请问这段代码的功能是什么?
package test; import java.awt.*; import javax.swing.*; import java.awt.event.*; import java.awt.event.InputEvent; import java.awt.event.KeyEvent; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JButton; import java.awt.BorderLayout; import java.awt.GridLayout; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import java.util.Random; public class Test3{ public static void main (String args[]) { Win win=new Win(); win.setTitle("输入序列号"); win.setBounds(10,10,460,360); } } class Police implements KeyListener,FocusListener{ public void keyPressed(KeyEvent e) { JTextField t=(JTextField)e.getSource(); if (t.getCarePosition()>=6) t.transferFocus(); } public void keyTyped(KeyEvent e) {} public void keyReleased(KeyEvent e) {} public void focusGained(FocusEvent e) { JTextField text=(JTextField)e.getSource(); text.setText(null); } public void focusLost(FocusEvent e){} } class Win extends JFrame { JTextField text[]=new JTextField[3]; Police police; JButton b; Win() { setLayout(new FlowLayout()); police = new Police(); for(int i=0;i<3;i++) { text[i]=new JTextField(7); text[i].addKeyListener(police); //监视键盘事件 text[i].addFocusListener(police); add(text[i]); } b=new JButton("确定"); add(b); setVisible(true); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); text[0].requestFocusInWindow(); } }哪里有错误
代码的缩进格式不够规范,需要进行调整。此外,代码中的一些注释也需要进行调整,以保证清晰易读。以下是修改后的代码:
```
package test;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.util.Random;
public class Test3{
public static void main (String args[]) {
Win win=new Win();
win.setTitle("输入序列号");
win.setBounds(10,10,460,360);
}
}
class Police implements KeyListener,FocusListener{
public void keyPressed(KeyEvent e) {
JTextField t=(JTextField)e.getSource();
if (t.getCarePosition()>=6)
t.transferFocus();
}
public void keyTyped(KeyEvent e) {}
public void keyReleased(KeyEvent e) {}
public void focusGained(FocusEvent e) {
JTextField text=(JTextField)e.getSource();
text.setText(null);
}
public void focusLost(FocusEvent e){}
}
class Win extends JFrame {
JTextField text[]=new JTextField[3];
Police police;
JButton b;
Win() {
setLayout(new FlowLayout());
police = new Police();
for(int i=0;i<3;i++) {
text[i]=new JTextField(7);
text[i].addKeyListener(police); //监视键盘事件
text[i].addFocusListener(police);
add(text[i]);
}
b=new JButton("确定");
add(b);
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
text[0].requestFocusInWindow();
}
}
```
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