问题
My question is I want to verify every two hour that there is new data in the database, for that I create this user interface :
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<EditText
android:id="@+id/speedAlert"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:ems="10"
android:gravity="center"
android:hint="km/h"
android:inputType="number" />
<CheckBox
android:id="@+id/checkBoxSpeed"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<Button
android:id="@+id/btnConfirmSpeed"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Confirm" />
so when user enter the value of the edittext and check the checkbox and confirm by clicking the button, an alarm is created and every two hour this alarm start a service :
btnConfirmSpeed.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
cal = Calendar.getInstance();
triggerAtTime = cal.getTimeInMillis()+ (1 * 30 * 60 * 1000); // starts in 30 minutes
repeat_alarm_every = (2 * 60 * 60 * 1000); // repeat every 2 hour
int _id = (int) System.currentTimeMillis();
Intent intent = new Intent(Alarm.this, NotificaSpeed.class);
//get the value of checkbox from sharedpreferences
boolean tgpref = pref.getBoolean("checkVitessePref", false);
String sp = speedAlert.getText().toString();
if(checkBoxSpeed.isChecked()){
if(sp.matches(""))
Toast.makeText(getApplicationContext(), "specify speed", Toast.LENGTH_SHORT).show();
else
{
editor = pref.edit();
editor.putBoolean("checkVitessePref", true); // value to store
editor.putInt("speedalarm", Integer.parseInt(speedAlert.getText().toString()));
editor.commit();
pintent = PendingIntent.getService(Alarm.this, _id, intent, 0);
alarm = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
alarm.setRepeating(AlarmManager.RTC_WAKEUP, triggerAtTime, repeat_alarm_every, pintent);
}
}else {
alarm.cancel(pintent);
editor.putBoolean("checkVitessePref", false); // value to store
editor.commit();
stopService(new Intent(Alarm.this,NotificaSpeed.class));
}
}
});
the NotificaSpeed is the service :
public class NotificaSpeed extends Service{
@Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
@Override
public void onCreate() {
mNotificationManager = (NotificationManager) getSystemService(ns);
super.onCreate();
}
@Override
public void onDestroy() {
super.onDestroy();
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
new VerifySpeedCar().execute();
return super.onStartCommand(intent, flags, startId);
}
public void notification(int carsNumber, int speed){
NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(NotificaSpeed.this);
if(carsNumber != 0)
notificationBuilder.setContentTitle(carsNumber+" cars are exceeding the speed");
.setSmallIcon(R.drawable.ic_launcher)
.setAutoCancel(true);
final int _idI = (int) System.currentTimeMillis();
Intent notificationIntent = new Intent(NotificaSpeed.this, ListCars.class);
PendingIntent contentIntent = PendingIntent.getActivity(this, _idI, notificationIntent, 0);
notificationBuilder.setContentIntent(contentIntent);
notificationBuilder.setDefaults(Notification.DEFAULT_SOUND | Notification.DEFAULT_LIGHTS | Notification.DEFAULT_VIBRATE);
mNotificationManager.notify(SIMPLE_NOTIFICATION_ID, notificationBuilder.build());
}
class VerifySpeedCar extends AsyncTask<String, String, String> {
protected String doInBackground(String... args) {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair(TAG_ACCOUNTID, accountID));
params.add(new BasicNameValuePair(TAG_SPEEDKPH, ""+speedpref)); // how can I get the value of edittext of the speed from the sharedpreferences?
JSONObject json = jParser.makeHttpRequest(url, "GET", params);
try {
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
cars = json.getJSONArray(TAG_CARS);
carsNumber = cars.length();
} else
carsNumber = 0;
} catch (JSONException e) {
e.printStackTrace();
}
}
return null;
}
protected void onPostExecute(String file_url) {
if( carsNumber != 0){
notification(carsNumber, speedpref);
}
}}}
first is that good way to do the verification or I am doing it wrong? second how can I get the value of the edittext from the sharedpreferences? finally when I close the app the service is stoped too, so when I start the app again the service is no more running but the value of checkbox is still checked, How can I resolve this?
thank you for taking the time to read my question. any help will be appreciated
回答1:
How to get the value of edittext from SharedPreference?
Create SharedPreference and SharedPreference.Editor objects.
SharedPreferences sp ;
sp = this.getSharedPreferences("YOUR PREF NAME", 0);
I believe you are getting the value from edittext in String str like
str = ed.getText().toString();
SharedPreferences.Editor editor = sp.edit();
editor.putString("edit_text", str);
editor.commit();
Retrieving the edittext value from SharedPreference
If you're retrieving in the same activity then
String value = sp.getString("edit_text", null);
If in different activity then first instantiate the SharedPreference like this
SharedPreference sp = this.getSharedPreferences("YOUR PREF NAME", 0);
来源：https://stackoverflow.com/questions/23539400/use-alarmmanager-and-service-to-get-data-from-server-repeatedly