Android 系统时间设置

一、自动确定时间

    /**
     * Get if the user prefers the date, time and timezone to be automatically fetched from the network 
     * @param context Context
     * @return ture=yes, false=no
     */
    public static boolean getTimeSettingAuto(Context context) {
        //Settings.System.AUTO_TIME was deprecated in API level 17.
        //Use Settings.Global.AUTO_TIME instead.
        int state = Settings.System.getInt(context.getContentResolver(), Settings.System.AUTO_TIME, 1);
        return (state == 1) ? true : false;
    }
    
    public static void setTimeSettingAuto(Context context, boolean isAuto) {
        Settings.System.putInt(context.getContentResolver(), Settings.System.AUTO_TIME, (isAuto ? 1 : 0));
    }

二、自动确定时区 （API11开始生效）

    /**
     * Get if the user prefers the timezone to be automatically fetched from the network 
     * @param context Context
     * @return ture=yes, false=no
     */
    public static boolean getTimezoneSettingAuto(Context context) {
        //Settings.System.AUTO_TIME_ZONE was useful from API 11.
        //Settings.System.AUTO_TIME_ZONE was deprecated in API level 17.
        //Use Settings.Global.AUTO_TIME_ZONE instead.
        int state = Settings.System.getInt(context.getContentResolver(), Settings.System.AUTO_TIME_ZONE, 1);
        return (state == 1) ? true : false;
    }
    
    public static void setTimezoneSettingAuto(Context context, boolean isAuto) {
        Settings.System.putInt(context.getContentResolver(), Settings.System.AUTO_TIME_ZONE, (isAuto ? 1 : 0));
    }

三、时间格式24/12

    /**
     * Get Display times style(12 or 24 hours)
     * @param context Context
     * @return ture=24, false=12
     */
    public static boolean is24HourFormat(Context context) {
        //Can use this to instand
        //return DateFormat.is24HourFormat(context);
        int state = Settings.System.getInt(context.getContentResolver(), Settings.System.TIME_12_24, 24);
        return (state == 24) ? true : false;
    }
    
    public static void set24HourFormat(Context context, boolean is24Style) {
        Settings.System.putInt(context.getContentResolver(), Settings.System.TIME_12_24, (is24Style ? 24 : 12));
        //Do not forget to inform system.
        Intent intent = new Intent(Intent.ACTION_TIME_CHANGED);
        context.sendBroadcast(intent);
    }

四、时区

    public static String getTimezoneId() {
        final TimeZone timeZone = TimeZone.getDefault();
        String id = timeZone.getID();
        return id;
    }
    
    public static void setTimezone(Context context, String zoneId) {
        final AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
        alarmManager.setTimeZone(zoneId);
        //DO not need send Intent.ACTION_TIMEZONE_CHANGED
        //Because system will send itself, and we do not have permission
    }

设置时区时需要添加权限

获取以及设置时区用到的都是TimezoneID，它们以字符串的形式存在。

可以用诸如"GMT+05:00", "GMT+0500", "GMT+5:00","GMT+500","GMT+05", and"GMT+5","GMT-05:00"的ID

Android系统用的ID一般为

中国标准时间 (北京)
香港时间 (香港)
台北时间 (台北)
首尔
日本时间 (东京)

五、系统时间

        Calendar calendar = Calendar.getInstance();
        mTimePicker.setIs24HourView(DateFormat.is24HourFormat(this));
        mTimePicker.setCurrentHour(calendar.get(Calendar.HOUR_OF_DAY));
        mTimePicker.setCurrentMinute(calendar.get(Calendar.MINUTE));

    public static void setTime(int hour, int minute) {
        Calendar calendar = Calendar.getInstance();
        
        //Calendar.HOUR_OF_DAY use 24 hour format
        //Calendar.HOUR_OF use 12 hour format, and we have to use calendar.set(Calendar.AM_PM, Calendar.PM);
        calendar.set(Calendar.HOUR_OF_DAY, hour);
        calendar.set(Calendar.MINUTE, minute);
        calendar.set(Calendar.SECOND, 0);
        
        long millis = calendar.getTimeInMillis();
        if ((millis / 1000) < Integer.MAX_VALUE) {
            SystemClock.setCurrentTimeMillis(millis);
        }
    }

但是SystemClock.setCurrentTimeMillis(millis);需要系统权限，解决办法请参见  增加修改系统时间权限

或者调出系统时间设置界面 startActivityForResult(new Intent(android.provider.Settings.ACTION_DATE_SETTINGS), 1);

六、日期格式

    public static String getDateFormat(Context context) {
        String fromat = Settings.System.getString(context.getContentResolver(), Settings.System.DATE_FORMAT);
        return fromat;
    }
    
    public static void setDateFormat(Context context, String dateFormat) {
        Settings.System.putString(context.getContentResolver(), Settings.System.DATE_FORMAT, dateFormat);
    }

日期格式一般的形式为：yyyy/MM/dd、yyyy MMM d、yyyy-MM-dd、yyyyMMdd

七、系统日期

        Calendar calendar = Calendar.getInstance();
        mDatePicker.updateDate(calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH), calendar.get(Calendar.DATE));

    public static void setDate(int year, int month, int day) {
        Calendar calendar = Calendar.getInstance();
        calendar.set(Calendar.YEAR, year);
        calendar.set(Calendar.MONTH, month);
        calendar.set(Calendar.DATE, day);
        
        long millis = calendar.getTimeInMillis();
        if ((millis / 1000) < Integer.MAX_VALUE) {
            SystemClock.setCurrentTimeMillis(millis);
        }
    }

同样的，SystemClock.setCurrentTimeMillis(millis);需要系统权限，解决办法请参见  增加修改系统时间权限