在我的 Android 程序中,我有一个微调器,允许用户选择不同的时间。每个选择都会用 Joda 时间进行处理以减去分钟。它在 0 到 59 分钟和 61 分钟及更长时间内工作正常。但是,减去 60 分钟后,时间不会更新,而是显示原始时间。
如何让 Joda 时间减去 60 分钟?
旋转器:
public class MyOnItemSelectedListener implements OnItemSelectedListener {
public void onItemSelected(AdapterView<?> parent, View view, int pos,
long id1) {
String mins = parent.getItemAtPosition(pos).toString();
int intmins=0;
// process user's selection of alert time
if(mins.equals("5 minutes")){intmins = 5;}
if(mins.equals("10 minutes")){intmins = 10;}
if(mins.equals("20 minutes")){intmins = 20;}
if(mins.equals("30 minutes")){intmins = 30;}
if(mins.equals("40 minutes")){intmins = 40;}
if(mins.equals("50 minutes")){intmins = 50;}
if(mins.equals("60 minutes")){intmins = 60;}
if(mins.equals("120 minutes")){intmins = 120;}
String stringMinutes=""+intmins;
setAlarm(intmins, stringMinutes);
} else {
}
public void onNothingSelected(AdapterView parent) {
mLocationDisplay.setText(" " + location);
}
}
public void setAlarm(int intmins, String mins) {
// based alarm time on start time of event. TODO get info from database.
String currentDate;
SimpleDateFormat myFormat = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss");
Date date1 = null;
DateTime dt;
currentDate = eventdate + " " + startTimeMilitary;// startTimeMilitary;
try {
date1 = myFormat.parse(currentDate);
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
dt = new DateTime(date1);
long dateInMillis = dt.getMillis();
String sDateInMillis = Long.toString(dateInMillis);
// subtract the selected time from the event's start time
String newAlertTime = subtractTime(dt, intmins);
newAlertTime = subtractTime(dt, intmins);
//......}
public String subtractTime(DateTime dt, int minusTime) {
DateTime greaterDate;
greaterDate = dt.minusMinutes(minusTime);
// newAlertTime is in UTC format
String newAlertTime = greaterDate.toString();
long alertInMillis = greaterDate.getMillis();
String sAlertInMillis = Long.toString(alertInMillis);
// ////new alert time is a stirng
setStringAlertInMillis(sAlertInMillis);
return newAlertTime;
}
最佳答案
1) 删除硬编码。
使用
final String mins = parent.getItemAtPosition(pos).toString();
final Pattern minutes = Pattern.compile("([0-9]+) minutes");
final Matcher m = minutes.matcher(mins);
String stringMinutes = "0";
if (mins.matches())
{
stringMinutes = m.group(1);
}
setAlarm(Integer.parseInt(stringMinutes), stringMinutes);
而不是你的硬编码
String mins = parent.getItemAtPosition(pos).toString();
// your hardcode is here
setAlarm(Integer.parseInt(stringMinutes), stringMinutes);
2) 使用 DateTimeFormatter
代替 SimpleDateFormatter
您使用 SimpleDateFormatter
获取 java Date
并按此日期创建 DateTime
。
DateTimeFormatter formatter = DateTimeFormat.forPattern("MM/dd/yyyy HH:mm:ss");
dt = formatter.parseDateTime(currentDate);
3) Joda 效果很好
在这段代码中,Joda 没有问题。
String subtractTime(DateTime dt, int minusTime)
应该可以很好地工作。
调试你的代码,问题出现在
if(mins.equals("5 minutes")){intmins = 5;}
if(mins.equals("10 minutes")){intmins = 10;}
//...
关于java - Joda Time 不能减去一小时,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/12568275/