在屏幕上显示日期时间星期的方法

一个获取当前时间的类：

import android.annotation.SuppressLint;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.widget.TextView;

import com.acmeinte.idl.sample.common.Constants;
import com.acmeinte.idl.sample.common.EventMsg;
import com.acmeinte.idl.sample.manager.DBFileManager;
import com.acmeinte.idl.sample.manager.DataMessage;

import org.greenrobot.eventbus.EventBus;

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;

//***
//更新时间类
//***
public class ThreadTime extends Thread {
    public TextView tvDate;
    private int msgKey1 = 22;

    public ThreadTime(TextView tvDate) {
        this.tvDate = tvDate;
    }

    @Override
    public void run() {
        do {
            try {
                Thread.sleep(1000);
                Message msg = new Message();
                msg.what = msgKey1;
                mHandler.sendMessage(msg);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        } while (true);
    }


    @SuppressLint("HandlerLeak")
    private Handler mHandler = new Handler() {
        @SuppressLint("SetTextI18n")
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            switch (msg.what) {
                case 22:
                    SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss");
                    String date = sdf.format(new Date());
                    tvDate.setText(deviceTime() + date + " " + getWeek());
                    65                     break;
                default:
                    break;
            }
        }
    };

    /**
     * 获取今天星期几
     *
     * @return
     */
    public static String deviceTime() {
        Calendar calendar = Calendar.getInstance();
        calendar.setTimeZone(TimeZone.getTimeZone("GMT+8:00"));
        String year;
        String month;
        String day;
        String deviceTime;

        year = String.valueOf(calendar.get(Calendar.YEAR));
        month = String.valueOf(calendar.get(Calendar.MONTH) + 1);
        day = String.valueOf(calendar.get(Calendar.DATE));
        deviceTime = year + "-" + month + "-" + day + " ";

        return deviceTime;
    }

    /**
     * 获取今天星期几
     *
     * @return
     */
    public static String getWeek() {
        Calendar calendar = Calendar.getInstance();
        int i = calendar.get(Calendar.DAY_OF_WEEK);
        switch (i) {
            case 1:
                return "周日";
            case 2:
                return "周一";
            case 3:
                return "周二";
            case 4:
                return "周三";
            case 5:
                return "周四";
            case 6:
                return "周五";
            case 7:
                return "周六";
            default:
                return "";
        }
    }

 131 }

然后再UI界面修改txt参数实现时间显示：

//时间

        TextView time_device ；
        time_device = findViewById(R.id.txt_time_device);
        ThreadTime threadTime = new ThreadTime(time_device);
        threadTime.start();