Question

我正在构建一个Android应用程序，它通过短信每月发送一次wifi使用数据。到目前为止，我已经设法通过短信发送wifi数据使用量，通过共享首选项保存应用程序首次启动的日期，以便以后可以访问 - 现在我需要找到一种方法使警报过期自我通过共享偏好保存之日起30天。这不应该太难 - 除了我需要检查每次设备启动时是否已经30天 - 以补偿手机可能关闭的时间。

有人可以帮助我实现这个目标吗？

SOURCE SNIPPET：

//获取当前日期日期日期=新日期（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));

完整来源：

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));
    }

}

第一次响应后更新的来源：

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("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);
    }

}

Answer 1

您无需检查已经过了多长时间。 AlarmManager.RTC_WAKEUP以实际UTC时间测量，与设备运行时间无关。

首先，你对invokeAlarm的调用应该只使用像

这样的东西

Calendar cal = Calendar.getInstance();
cal.setTime(myDate);
cal.add(Calendar.DATE, 30);
invokeAlarm(cal.getTimeInMillis(), rowId);

请注意，AlarmManager在重启时会丢失所有警报。您需要为“Intent.ACTION_BOOT_COMPLETED”意图设置一个广播接收器服务。

在此服务中，只需使用相同的逻辑再次设置闹钟。

Android报警基于共享首选项中存储的时间

第一次响应后更新的来源：

1 个答案: