public void action(){ Thread thread = new Thread(); @Override public void run(){ while(true){ try { Thread.sleep(10); }catch (InterruptedException e) { // TODO: handle exception e.printStackTrace(); } repaint(); } };

这段代码仍然存在一些问题。下面是对代码进行修正的建议：

public void action() {
    Thread thread = new Thread() {
        @Override
        public void run() {
            while (true) {
                try {
                    Thread.sleep(10);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                repaint();
            }
        }
    };
    thread.start();
}

修正后的代码中，我们在创建线程对象时直接使用了匿名内部类来重写`run`方法。然后调用`start()`方法来启动线程。

请注意，这段代码依然需要在适当的上下文环境中使用，比如在一个继承自`Canvas`或`JPanel`的组件类中调用`action()`方法。

如果你有任何进一步的问题，请随时提问。

相关问题

安卓service的开启线程 并每隔一段时间传回主方法结果详细代码

以下是一个示例代码，其中包含一个Service类和一个MainActivity类。

Service类：

public class MyService extends Service {

    private boolean isRunning = false;
    private int counter = 0;

    @Override
    public void onCreate() {
        super.onCreate();
        isRunning = true;
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        new Thread(new Runnable() {
            @Override
            public void run() {
                while (isRunning) {
                    Log.d("MyService", "Counter: " + counter);
                    // 模拟耗时操作
                    try {
                        Thread.sleep(5000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    // 发送广播通知主方法
                    Intent broadcastIntent = new Intent();
                    broadcastIntent.setAction("com.example.myapp.COUNTER_UPDATE");
                    broadcastIntent.putExtra("counter", counter);
                    sendBroadcast(broadcastIntent);
                    counter++;
                }
            }
        }).start();

        return START_STICKY;
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        isRunning = false;
    }

    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }
}

MainActivity类：

public class MainActivity extends AppCompatActivity {

    private TextView counterTextView;

    private BroadcastReceiver counterUpdateReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            int counter = intent.getIntExtra("counter", 0);
            counterTextView.setText("Counter: " + counter);
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        counterTextView = findViewById(R.id.counterTextView);

        // 启动Service
        Intent serviceIntent = new Intent(this, MyService.class);
        startService(serviceIntent);

        // 注册广播接收器
        IntentFilter filter = new IntentFilter();
        filter.addAction("com.example.myapp.COUNTER_UPDATE");
        registerReceiver(counterUpdateReceiver, filter);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();

        // 停止Service
        Intent serviceIntent = new Intent(this, MyService.class);
        stopService(serviceIntent);

        // 注销广播接收器
        unregisterReceiver(counterUpdateReceiver);
    }
}

在上述代码中，Service类中的onStartCommand()方法中开启了一个新线程，该线程每隔5秒向Logcat输出一个计数器的值，并发送一个广播通知MainActivity类更新UI。MainActivity类中注册了一个广播接收器，用于接收Service类发送的广播，并更新UI。需要注意的是，在MainActivity类中启动Service和注册广播接收器时，需要使用相同的Action字符串，以便正确匹配广播。

在接收到ACTION_MEDIA_EJECT或者ACTION_MEDIA_UNMOUNTED广播后，可以通过以下步骤使U盘成功卸载，不会再下次插入的时候系统提示“vold : ForceUnmount failed: Device or resource busy”： 停止对U盘中工厂apk的读写操作，即关闭工厂apk应用程序。 关闭U盘中工厂apk应用程序所打开的所有文件和流。 关闭U盘中工厂apk应用程序所占用的所有资源。 等待一段时间，确保U盘中工厂apk应用程序已经完全释放了对U盘的占用。 卸载U盘。 另外，为了避免下次插入时提示“vold : ForceUnmount failed: Device or resource busy”，可以在卸载U盘后，检查U盘是否已经完全卸载，如果没有完全卸载，可以尝试强制卸载U盘。如果还是不行，可以重启设备再尝试卸载。 请详细写出代码实现方式

以下是示例代码实现方式：

public class MainActivity extends AppCompatActivity {

    private static final String FACTORY_APK_NAME = "factory.apk";
    private static final String FACTORY_APK_PACKAGE_NAME = "com.example.factory";
    private static final int WAIT_TIME = 5000; // 等待时间，单位为毫秒

    private boolean mIsFactoryApkRunning = false;
    private boolean mIsUninstalling = false;

    private BroadcastReceiver mUsbReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            switch (intent.getAction()) {
                case Intent.ACTION_MEDIA_MOUNTED:
                    // 获取U盘中的工厂apk信息
                    String apkPath = getFactoryApkPath(context);
                    if (apkPath != null) {
                        // 启动工厂apk
                        startFactoryApk(context, apkPath);
                    }
                    break;
                case Intent.ACTION_MEDIA_EJECT:
                case Intent.ACTION_MEDIA_UNMOUNTED:
                    // 停止工厂apk
                    stopFactoryApk(context);
                    // 卸载U盘
                    uninstallUsb(context);
                    break;
            }
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // 注册U盘相关广播接收器
        IntentFilter filter = new IntentFilter();
        filter.addAction(Intent.ACTION_MEDIA_MOUNTED);
        filter.addAction(Intent.ACTION_MEDIA_EJECT);
        filter.addAction(Intent.ACTION_MEDIA_UNMOUNTED);
        filter.addDataScheme("file");
        registerReceiver(mUsbReceiver, filter);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        // 注销U盘相关广播接收器
        unregisterReceiver(mUsbReceiver);
    }

    private String getFactoryApkPath(Context context) {
        String apkPath = null;
        File usbRoot = getUsbRoot(context);
        if (usbRoot != null) {
            File[] files = usbRoot.listFiles(new FilenameFilter() {
                @Override
                public boolean accept(File dir, String name) {
                    return name.equals(FACTORY_APK_NAME);
                }
            });
            if (files != null && files.length > 0) {
                apkPath = files[0].getAbsolutePath();
            }
        }
        return apkPath;
    }

    private File getUsbRoot(Context context) {
        File usbRoot = null;
        StorageManager storageManager = (StorageManager) context.getSystemService(Context.STORAGE_SERVICE);
        try {
            String[] volumePaths = (String[]) storageManager.getClass().getMethod("getVolumePaths").invoke(storageManager);
            for (String path : volumePaths) {
                File file = new File(path);
                if (file.exists() && file.isDirectory() && file.canRead()) {
                    StatFs statFs = new StatFs(file.getAbsolutePath());
                    if (statFs.getBlockCountLong() > 0 && statFs.getBlockSizeLong() > 0 &&
                            statFs.getAvailableBlocksLong() * statFs.getBlockSizeLong() > 0) {
                        usbRoot = file;
                        break;
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return usbRoot;
    }

    private void startFactoryApk(Context context, String apkPath) {
        if (mIsFactoryApkRunning) {
            return;
        }
        Intent intent = context.getPackageManager().getLaunchIntentForPackage(FACTORY_APK_PACKAGE_NAME);
        if (intent == null) {
            intent = new Intent(Intent.ACTION_VIEW);
            intent.setDataAndType(Uri.fromFile(new File(apkPath)), "application/vnd.android.package-archive");
        }
        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        context.startActivity(intent);
        mIsFactoryApkRunning = true;
    }

    private void stopFactoryApk(Context context) {
        if (!mIsFactoryApkRunning) {
            return;
        }
        ActivityManager activityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
        List<ActivityManager.RunningAppProcessInfo> processInfoList = activityManager.getRunningAppProcesses();
        for (ActivityManager.RunningAppProcessInfo processInfo : processInfoList) {
            if (processInfo.processName.equals(FACTORY_APK_PACKAGE_NAME)) {
                android.os.Process.killProcess(processInfo.pid);
                break;
            }
        }
        mIsFactoryApkRunning = false;
    }

    private void uninstallUsb(final Context context) {
        if (mIsUninstalling) {
            return;
        }
        mIsUninstalling = true;
        new Thread(new Runnable() {
            @Override
            public void run() {
                while (isFactoryApkRunning(context)) {
                    try {
                        Thread.sleep(WAIT_TIME);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
                String path = getUsbRoot(context).getAbsolutePath();
                String cmd = "pm uninstall " + path;
                try {
                    Runtime.getRuntime().exec(cmd);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                mIsUninstalling = false;
            }
        }).start();
    }

    private boolean isFactoryApkRunning(Context context) {
        ActivityManager activityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
        List<ActivityManager.RunningAppProcessInfo> processInfoList = activityManager.getRunningAppProcesses();
        for (ActivityManager.RunningAppProcessInfo processInfo : processInfoList) {
            if (processInfo.processName.equals(FACTORY_APK_PACKAGE_NAME)) {
                return true;
            }
        }
        return false;
    }
}

以上是一个简单的示例代码实现方式，具体实现方式可能会因为需求和环境的不同而有所不同。