原帖:
在以下示例中:
如何在 SharedPreferences 中保存和检索日期
我应该寻找什么来替换 ... ?
Save:
SharedPreferences prefs = ...;
SharedPreferences.Editor editor = prefs.edit();
editor.putLong("time", date.getTime());
editor.commit()
我正在尝试使用诸如:
SharedPreferences.Editor editor = getSharedPreferences(DATE_PREF, MODE_PRIVATE);
但我收到一条错误消息,指出 DATE_PREF 无法解析为变量。
MY SOURCE:
//get the current date
Date date = new Date(System.currentTimeMillis());
// convert the date to milliseconds
long millis = date.getTime();
// save the date to shared preferences
SharedPreferences prefs = millis ;
SharedPreferences.Editor editor = getSharedPreferences(DATE_PREF, MODE_PRIVATE);
editor.putLong("time", date.getTime());
editor.commit();
第一次响应后更新:(仍然需要帮助)
删除线后:
// SharedPreferences prefs = millis;
// SharedPreferences.Editor editor = PreferenceManager
// .getDefaultSharedPreferences(getApplicationContext())
我在以下位置收到两个错误,说明“无法解析编辑器”:
editor.putLong("time", date.getTime());
editor.commit();
由于我删除了引用编辑器的行 - 我的问题是:我的偏好是否仍会保存如下所示?(我需要这个值在重启后保持不变。)
我试过使用:
SharedPreferences.putLong("时间", date.getTime()); SharedPreferences.commit();
也:
putLong("时间", date.getTime()); 犯罪();
但是,这两种方法都会导致错误,我只想确保重新启动后将存储这些值。
public class WifiMonitor extends Activity {
Button sendButton;
EditText msgTextField;
private PendingIntent pendingIntent;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
TextView infoView = (TextView) findViewById(R.id.traffic_info);
// get traffic info
double totalBytes = (double) TrafficStats.getTotalRxBytes()
+ TrafficStats.getTotalTxBytes();
double mobileBytes = TrafficStats.getMobileRxBytes()
+ TrafficStats.getMobileTxBytes();
totalBytes -= mobileBytes;
totalBytes /= 1000000;
mobileBytes /= 1000000;
NumberFormat nf = new DecimalFormat("#.##");
String totalStr = nf.format(totalBytes);
String mobileStr = nf.format(mobileBytes);
String info = String.format(
"Wifi Data Usage: %s MB\tMobile Data Usage: %s MB", totalStr,
mobileStr);
infoView.setText(info);
// send traffic info via sms
SmsManager smsManager = SmsManager.getDefault();
smsManager.sendTextMessage("7862611848", null, info, null, null);
String alarm = Context.ALARM_SERVICE;
// get the current date
Date date = new Date(System.currentTimeMillis());
// convert the date to milliseconds
long millis = date.getTime();
// save the date to shared preferences
SharedPreferences prefs = PreferenceManager
.getDefaultSharedPreferences(getApplicationContext());
// SharedPreferences prefs = millis;
// SharedPreferences.Editor editor = PreferenceManager
// .getDefaultSharedPreferences(getApplicationContext());
editor.putLong("time", date.getTime());
editor.commit();
// get the saved date
Date myDate = new Date(prefs.getLong("time", 0));
}
// set the alarm to expire 30 days from the date stored in sharePreferences
public void invokeAlarm(long invokeTime, long rowId) {
AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
Intent i = new Intent(this, Alarm.class);
i.putExtra("rowId", String.valueOf(rowId));
am.set(AlarmManager.RTC_WAKEUP, invokeTime, PendingIntent.getService(
this, (int) System.currentTimeMillis(), i, 0));
}
}