从一年中的日期获取日期名称android

Question

我想从android中的一年中的天数中获取星期几的名称。示例：2016 年第 344 天的日期名称是什么。我的服务器给了我这样的数据并且必须使用它来找出日期名称。

{
  "id": 106,
  "month": 12,
  "year": 2016,
  "yDay": 344,
  "hour": 19
}

我可以从日历中获取当前日期。

Calendar calendar = Calendar.getInstance(); int dayOfYear = calendar.get(Calendar.DAY_OF_YEAR);

Answer 1

您可以从日期获取dayOfWeek（从yDay，month，year形成日期）

Calendar c = Calendar.getInstance();
c.setTime(yourDate);
int dayOfWeek = c.get(Calendar.DAY_OF_WEEK);

Answer 2

首先，您需要使用年份和年份初始化一个Calendar 实例：

Calendar c = Calendar.getInstance();
c.set(Calendar.DAY_OF_YEAR, yourDayOfYear);
c.set(Calendar.YEAR, yourYear);

然后你可以从Calendar获取星期几

int dayOfWeek = c.get(Calendar.DAY_OF_WEEK);

Answer 3

通过以下方式实现它的一种方法：

 public String getNameOfDay(int year, int dayOfYear) {

    Calendar calendar = Calendar.getInstance();
    calendar.set(Calendar.YEAR, year);
    calendar.set(Calendar.DAY_OF_YEAR, dayOfYear);
    String days[] = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};

    int dayIndex = calendar.get(Calendar.DAY_OF_WEEK);

    return days[dayIndex - 1];
}                    

Answer 4

您可以直接从 Calendar 对象中以字符串形式获取星期几：

Calendar cal = Calendar.getInstance();
cal.set(Calendar.DAY_OF_YEAR, dayOfYear); // Set the day of the year value
String day = cal.getDisplayName(Calendar.DAY_OF_WEEK, Calendar.LONG, Locale.US); 
// Use Calendar.SHORT for abbreviated names or .LONG for full names
// and be sure to change the locale as necessary

Answer 5

What is the easiest way to get the current day of the week in Android?

因此您将获得当前日期，并且您将以相同的方式获得当前日期以及相同日期的天数。现在计算一下

Answer 6

试试这个，它会根据你的年份和月份给你名字

// Assuming that you already have this.
    int year = 2016;
    int month = 12;
    int day = 2;

    // First convert to Date. This is one of the many ways.
    String dateString = String.format("%d-%d-%d", year, month, day);
    Date date = new SimpleDateFormat("yyyy-M-d").parse(dateString);

    // Then get the day of week from the Date based on specific locale.
    String dayOfWeek = new SimpleDateFormat("EEEE", Locale.ENGLISH).format(date);

    System.out.println(dayOfWeek); // Friday

如果你有日期格式，那么你可以试试这个

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    dayName("2016-12-02 00:00:00", "YYYY-MM-DD HH:MM:ss")
}

public static String dayName(String inputDate, String format){
    Date date = null;
    try {
       date = new SimpleDateFormat(format).parse(inputDate);
    } catch (ParseException e) {
       e.printStackTrace();
    }
   return new SimpleDateFormat("EEEE", Locale.ENGLISH).format(date);
}

Answer 7

实现此目的的另一种方法是使用 Joda Time Package。 Android 目前仅在 Java 1.7 上运行，因此本身不具备良好的时间特性。

将 Joda Time 添加到您的build.gradle：

compile 'joda-time:joda-time:2.9.4'

然后你可以做类似这样的事情：

public String getNameOfDay(int year, int yDay) {

    String pattern = year + ";" + yDay;

    DateTimeFormatter dateTimeFormatter = DateTimeFormat.forPattern("y;D");
    DateTime requestedDate = DateTime.parse(pattern, dateTimeFormatter);
    int dayOfWeek = requestedDate.getDayOfWeek();

    //Notice that Monday is 1 and Sunday is 7
    String[] days = {"Monday", "Tuesday", "Thursday", "Friday", "Saturday", "Sunday"};
    return days[dayOfWeek - 1];
}

请注意，我只是提供了一种替代已发布的实现此目标的方法。如果您不想在您的项目中添加 joda 时间，您可以按照其他人已经说过的方式进行。

Answer 8

这是我使用的方法，并确保您使用相同的格式，这意味着不要使用 - 而不是 /，反之亦然：

 public String getDayName(String date) {
        SimpleDateFormat df = new SimpleDateFormat("M-d-yyyy", Locale.getDefault());

        Date readDate=null;
        try {
            readDate = df.parse(date);
        } catch (ParseException e) {
            e.printStackTrace();
        }
        Calendar c = Calendar.getInstance();
        c.setTime(Objects.requireNonNull(readDate));

        int dayOfWeek = c.get(Calendar.DAY_OF_WEEK);
        String[] days = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};

        return days[dayOfWeek-1];
    }