//currentTimeMillis is System.currentTimeMillis()

    long totalSeconds = currentTimeMillis / 1000;
    int currentSecond = (int)totalSeconds % 60;

    long totalMinutes = totalSeconds / 60;
    int currentMinute = (int)totalMinutes % 60;

    long totalHours = totalMinutes / 60;
    int currentHour = (int)totalHours % 12;

    TextView tvTime = findViewById(R.id.tvTime);
    tvTime.setText((currentHour + OR - TIME YOU ARE FROM GMT) + ":" + currentMinute + ":" + currentSecond);

您应该根据新的API使用calendar类。Date类现在已弃用。

Calendar cal = Calendar.getInstance();

String date = "" + cal.get(Calendar.DATE) + "-" + (cal.get(Calendar.MONTH)+1) + "-" + cal.get(Calendar.YEAR);

String time = "" + cal.get(Calendar.HOUR_OF_DAY) + ":" + cal.get(Calendar.MINUTE);

试试这段代码。它显示当前的日期和时间。

 Date date = new Date(System.currentTimeMillis());
 SimpleDateFormat dateFormat = new SimpleDateFormat("hh:mm aa",
                         Locale.ENGLISH);
 String var = dateFormat.format(date));

试着用简单的方法获取当前的日期和时间:

SimpleDateFormat sdf = new SimpleDateFormat("yyyy.MM.dd G 'at' HH:mm:ss z");
String currentDateandTime = sdf.format(new Date());

你可以通过以下方法获取日期:

Time t = new Time(Time.getCurrentTimezone());
t.setToNow();
String date = t.format("%Y/%m/%d");

这将给你一个漂亮的表单结果，如这个例子:"2014/02/09"。

如果你想以特定的模式获取日期和时间，你可以使用以下命令:

SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd_HHmmss", Locale.getDefault());
String currentDateandTime = sdf.format(new Date());

Or,

日期:

String currentDate = new SimpleDateFormat("dd-MM-yyyy", Locale.getDefault()).format(new Date());

时间:

String currentTime = new SimpleDateFormat("HH:mm:ss", Locale.getDefault()).format(new Date());