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[英]AsyncTask that checks current session based on time stored in shared preferences
[英]Android Alarm Based On a Time Stored in Shared Preferences
我正在構建一個Android應用程序,該應用程序每月通過短信發送一次wifi使用情況數據。 到目前為止,我已經設法通過短信發送了wifi數據使用量,並通過共享首選項保存了首次啟動該應用程序的日期,以便以后可以訪問它-現在,我需要找到一種使警報到期的方法從我通過共享首選項保存之日起30天。 這應該不太困難-除非我需要檢查每次啟動設備是否都已經30天了,以補償手機可能已經關機的時間。
有人可以幫我做到這一點嗎?
源片段:
//獲取當前日期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 = 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 (this portion is not functional - and it is what I need help with)
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));
來源:
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("7865555555", 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 = 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 (this portion is not functional - and it is what I need help with)
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));
}
}
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));
Calendar cal = Calendar.getInstance();
cal.setTime(myDate);
cal.add(Calendar.DATE, 30);
invokeAlarm(cal.getTimeInMillis(), rowId);
}
}
您無需檢查已花費了多少時間。 AlarmManager.RTC_WAKEUP
以實際UTC時間測量,與設備正常運行時間無關。
因此,首先您對invokeAlarm的調用應該只使用類似
Calendar cal = Calendar.getInstance();
cal.setTime(myDate);
cal.add(Calendar.DATE, 30);
invokeAlarm(cal.getTimeInMillis(), rowId);
請注意,AlarmManager在重新啟動后會丟失所有警報。 您需要為“ Intent.ACTION_BOOT_COMPLETED”意圖設置作為廣播接收器的服務。
在此服務中,只需使用相同的邏輯再次設置警報即可。
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