NotificationChannel不适用于安卓8及更高版本

import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.content.Context;
import android.os.Build;

public class NotificationHelper {
    private static final String CHANNEL_ID = "default_channel_id";
    private static final String CHANNEL_NAME = "Default Channel";

    public static void createNotificationChannel(Context context) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            NotificationChannel channel = new NotificationChannel(
                    CHANNEL_ID,
                    CHANNEL_NAME,
                    NotificationManager.IMPORTANCE_DEFAULT
            );
            channel.setDescription("This is the default notification channel");

            NotificationManager notificationManager = context.getSystemService(NotificationManager.class);
            notificationManager.createNotificationChannel(channel);
        }
    }
}

public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        NotificationHelper.createNotificationChannel(this);
    }
}