如何在Android应用程序中获取当前时间和日期?


当前回答

final Calendar c = Calendar.getInstance();
int mYear = c.get(Calendar.YEAR);
int mMonth = c.get(Calendar.MONTH);
int mDay = c.get(Calendar.DAY_OF_MONTH);

textView.setText("" + mDay + "-" + mMonth + "-" + mYear);

其他回答

对于当前带格式的日期和时间,使用:

在Java中

Calendar c = Calendar.getInstance();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String strDate = sdf.format(c.getTime());
Log.d("Date", "DATE: " + strDate)

在Kotlin

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
    val current = LocalDateTime.now()
    val formatter = DateTimeFormatter.ofPattern("dd.MM.yyyy. HH:mm:ss")
    var myDate: String =  current.format(formatter)
    Log.d("Date", "DATE: " + myDate)
} else {
    var date = Date()
    val formatter = SimpleDateFormat("MMM dd yyyy HH:mma")
    val myDate: String = formatter.format(date)
    Log.d("Date", "DATE: " + myDate)
}

日期格式化程序模式

"yyyy.MM.dd G 'at' HH:mm:ss z" ---- 2001.07.04 AD at 12:08:56 PDT
"hh 'o''clock' a, zzzz" ----------- 12 o'clock PM, Pacific Daylight Time
"EEE, d MMM yyyy HH:mm:ss Z"------- Wed, 4 Jul 2001 12:08:56 -0700
"yyyy-MM-dd'T'HH:mm:ss.SSSZ"------- 2001-07-04T12:08:56.235-0700
"yyMMddHHmmssZ"-------------------- 010704120856-0700
"K:mm a, z" ----------------------- 0:08 PM, PDT
"h:mm a" -------------------------- 12:08 PM
"EEE, MMM d, ''yy" ---------------- Wed, Jul 4, '01

实际上,使用time . getcurrenttimezone()在设备上设置当前时区更安全,否则您将获得UTC的当前时间。

Time today = new Time(Time.getCurrentTimezone());
today.setToNow();

然后,你可以得到你想要的所有日期字段,例如:

textViewDay.setText(today.monthDay + "");             // Day of the month (1-31)
textViewMonth.setText(today.month + "");              // Month (0-11)
textViewYear.setText(today.year + "");                // Year 
textViewTime.setText(today.format("%k:%M:%S"));  // Current time

详情请参阅android.text.format.Time类。

更新

正如许多人指出的那样,谷歌说这个类有一些问题,不应该再使用了:

This class has a number of issues and it is recommended that GregorianCalendar is used instead. Known issues: For historical reasons when performing time calculations all arithmetic currently takes place using 32-bit integers. This limits the reliable time range representable from 1902 until 2037.See the wikipedia article on the Year 2038 problem for details. Do not rely on this behavior; it may change in the future. Calling switchTimezone(String) on a date that cannot exist, such as a wall time that was skipped due to a DST transition, will result in a date in 1969 (i.e. -1, or 1 second before 1st Jan 1970 UTC). Much of the formatting / parsing assumes ASCII text and is therefore not suitable for use with non-ASCII scripts.

你可以简单地使用下面的代码:

 DateFormat df = new SimpleDateFormat("HH:mm"); // Format time
 String time = df.format(Calendar.getInstance().getTime());

 DateFormat df1 = new SimpleDateFormat("yyyy/MM/dd"); // Format date
 String date = df1.format(Calendar.getInstance().getTime());
final Calendar c = Calendar.getInstance();
int mYear = c.get(Calendar.YEAR);
int mMonth = c.get(Calendar.MONTH);
int mDay = c.get(Calendar.DAY_OF_MONTH);

textView.setText("" + mDay + "-" + mMonth + "-" + mYear);

你可以(但不再应该-见下文!)使用android.text.format.Time:

Time now = new Time();
now.setToNow();

从上面的参考链接:

Time类是一个更快的替代品 为java.util.Calendar和 java.util.GregorianCalendar类。 Time类的实例 表示指定的时间点 精准度第二。


注1: 我写这个答案已经有好几年了, 它是关于一个旧的,android专用的,现在已被弃用的类。 谷歌现在这样说 “他的类有一些问题,建议使用公历代替”。


注2:尽管Time类有一个toMillis(ignoreDaylightSavings)方法,但这只是为了方便传递给以毫秒为单位的方法。时间值仅精确到一秒;毫秒部分总是000。如果在循环中,你会这样做

Time time = new Time();   time.setToNow();
Log.d("TIME TEST", Long.toString(time.toMillis(false)));
... do something that takes more than one millisecond, but less than one second ...

结果序列将重复相同的值,例如1410543204000,直到下一秒开始,此时1410543205000将开始重复。