Swing UI线程安全操作

绝地灬酷狼 2022-08-18 11:45 170阅读 0赞

**1. Timer的使用**  
举例：点击按钮，按进度条没隔一秒就增加十分之一

import java.awt.BorderLayout;
    
    public class TestTimer extends JFrame {
        
    
        private JPanel contentPane;
        int value=0;
        private JProgressBar progressBar;
        /**
         * Launch the application.
         */
        public static void main(String[] args) {
            EventQueue.invokeLater(new Runnable() {
                public void run() {
                    try {
                        TestTimer frame = new TestTimer();
                        frame.setVisible(true);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            });
        }
    
        /**
         * Create the frame.
         */
        public TestTimer() {
            setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            setBounds(100, 100, 450, 300);
            contentPane = new JPanel();
            contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
            contentPane.setLayout(new BorderLayout(0, 0));
            setContentPane(contentPane);
            progressBar = new JProgressBar();
            contentPane.add(progressBar, BorderLayout.NORTH);
            JButton btnRun = new JButton("start");
            btnRun.addMouseListener(new MouseAdapter() {
                @Override
                public void mouseClicked(MouseEvent e) {
                    Timer timer = new Timer(1000, new ActionListener() {
                        @Override
                        public void actionPerformed(ActionEvent e) {
                            value +=10;
                            progressBar.setValue(value);
                            if (value==100) {
                                value=0;
                            }
                        }
                    });
                    timer.setRepeats(true);
                    timer.start();
                }
            });
            contentPane.add(btnRun, BorderLayout.CENTER);
        }
    }

**2. SwingWorker**  
举例：点击按钮，在文本框内获取网站的数据

import java.awt.BorderLayout;
    import java.awt.EventQueue;
    import java.awt.event.MouseAdapter;
    import java.awt.event.MouseEvent;
    import java.io.BufferedReader;
    import java.io.InputStreamReader;
    import java.net.URL;
    import java.net.URLConnection;
    import java.util.List;
    import java.util.concurrent.ExecutionException;
    
    import javax.swing.JButton;
    import javax.swing.JFrame;
    import javax.swing.JPanel;
    import javax.swing.JScrollPane;
    import javax.swing.JTextArea;
    import javax.swing.SwingWorker;
    import javax.swing.border.EmptyBorder;
    
    public class TestSwingworker extends JFrame {
        
    
        private JPanel contentPane;
        private JTextArea textArea;
    
        /**
         * Launch the application.
         */
        public static void main(String[] args) {
            EventQueue.invokeLater(new Runnable() {
                public void run() {
                    try {
                        TestSwingworker frame = new TestSwingworker();
                        frame.setVisible(true);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            });
        }
    
        /**
         * Create the frame.
         */
        public TestSwingworker() {
            setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            setBounds(100, 100, 450, 300);
            contentPane = new JPanel();
            contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
            contentPane.setLayout(new BorderLayout(0, 0));
            setContentPane(contentPane);
    
            JButton btnNewButton = new JButton("run");
            btnNewButton.addMouseListener(new MouseAdapter() {
                @Override
                public void mouseClicked(MouseEvent e) {
                    webRead();
                }
            });
            contentPane.add(btnNewButton, BorderLayout.NORTH);
    
            JScrollPane scrollPane = new JScrollPane();
            contentPane.add(scrollPane, BorderLayout.CENTER);
    
            textArea = new JTextArea();
            scrollPane.setViewportView(textArea);
        }
        public void  webRead() {
            new SwingWorker<StringBuilder,String>(){
                @Override
                protected StringBuilder doInBackground() throws Exception {
                    URL url = new URL("http://www.baidu.com");
                    URLConnection connection = url.openConnection();
                    BufferedReader reader = new BufferedReader(
                            new InputStreamReader(connection.getInputStream(),"utf-8"));
                    String line;
                    StringBuilder builder = new StringBuilder();
                    while((line = reader.readLine())!=null){
                        //publish(line);//调用process()方法
                        builder.append(line).append("\n");
                    }
                    reader.close();
                    return builder;
                }
    
                @Override
                protected void process(List<String> chunks) {
                    for (String line:chunks) {
                        textArea.append(line);
                        textArea.append("\n");
                    }
                    super.process(chunks);
                }
    
                @Override
                protected void done() {
                    try {
                        //get得到的是doInBackground()返回值
                        textArea.setText(get().toString());
                    } catch (InterruptedException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    } catch (ExecutionException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                    super.done();
                }
    
            }.execute();
        }
    }