How to store a Cookie as persistent data? - android

When connected to the server i get the Cookies and store them in a List.
While making connections later i add these cookies to the DefaultHttpClient.
The problem is, when the Application is in background for sometime, all the class data is being lost including the DefaultHttpClient.
Hence i am losing the cookie.
Is there a way to keep the DefaultHttpClient alive forever?
or any better way to store and use cookies?
Thank You

Get it from the cookie, then save it in the shared prefferences when the app is killed (e.g. onStop method). Then reload it on onCreate(). Something similar to this:
public class Calc extends Activity {
public static final String PREFS_NAME = "MyPrefsFile";
#Override
protected void onCreate(Bundle state){
super.onCreate(state);
. . .
// Restore preferences
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
String silent = settings.getString("cookie", null);
if(cookie == null) {
// first time, get cookie again and save it
} else {
// set cookie manually for HTTPClient
}
}
#Override
protected void onStop(){
super.onStop();
// We need an Editor object to make preference changes.
// All objects are from android.context.Context
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editor = settings.edit();
editor.putString("cookie", theCookie);
// Commit the edits!
editor.commit();
}
}
(I have omited the code for getting and setting the cookie, I assume that's not a problem)

Related

Can SharedPreferences be not saving?

I have one application that uses SharedPreferences to record the checkin or checkout state of the user.
If the checkin is pressed, it's button is grayed out the checkout becomes available, the opposite work as well.
However some users tells me that "sometimes" they will make another checkin on the next day and the checkout is still available.
Im supecting that they are forgetting to tap it, but i want to know if is there by any chance that this SharedPreferencces get cleared by itself?
this is the part of my code that i save the checkin state:
SharedPreferences preferences = getSharedPreferences("MyPreferences", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = preferences.edit();
editor.putInt("statuscheckin", 1); //1 for checkin, 0 for checkout
editor.commit();
this is the part where i check it
if (getSharedPreferences("MyPreferences", Context.MODE_PRIVATE).getInt("statuscheckin", 0) == 1) {...}
Unless you clear the storage/cache, SharedPreferences won't get cleared by itself.
Make sure you are not clearing it by yourself for any condition happening.
If you are getting the default value only, it's possible that you are using it before the value gets committed.
Try this code,
Session Manager code:
SharedPreferences sharedPreferences;
SharedPreferences.Editor editor;
Context context;
public static final String KEY_CHECKIN= "checkin";
public void setCheckin(boolean login){
editor = sharedPreferences.edit();
editor.putBoolean(KEY_CHECKIN,checkin);
editor.apply();
}
public boolean getCheckin(){
return sharedPreferences.getBoolean(KEY_CHECKIN,false);
}
In your Java code:
SessionManager sessionmanager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
sessionmanager = new SessionManager(this);
//Condition for checkin
if(user checkedIn){
sessionmanager.setCheckin(true);}
//Retrieving the value when user again opens the app:
if(sessionmanager.getCheckin()){}////proceed with your logic.

Shared Preferences not persistent after app restart

I found all answers here and tried all solutions, still my shared prefs are not persistent.
Here's my code:
public static void setActivated(boolean activated) {
SharedPreferences sp = Utils.getContext().getSharedPreferences(
USER_PREFS, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sp.edit();
editor.putBoolean(ASD, activated);
editor.commit();
}
public static boolean isActivated() {
SharedPreferences sp = Utils.getContext().getSharedPreferences(USER_PREFS, Context.MODE_PRIVATE);
return sp.getBoolean(ASD, true);
}
I've tried also:
editor.clear();
editor.put ..
editor.commit();
I've also tried with
editor.apply();
I even tried with both .apply() and .commit() and no luck.
Another idea was to try using a different mode for the files:
...getSharedPreferences(USER_PREFS, Context.MODE_MULTI_PROCESS);
The problem is that the values saved are not persistent. If I close the app and then re-open it the values are all wrong.
Does anyone have any ideas? I would also mention that the problem is only on some devices, for example HTC One S, Samsung Galaxy S3 (I tested on a different S3 and it worked perfectly).
EDIT: I call the save on a button click listener and I call isActivated when I load the fragment (after onViewCreated()).
Thanks!
Hi I think it should work. If clearing does not work, you could try the second option as detailed in my solution:
You have 2 options:
Get shared preference value during the life-cycle of the activity.
Call .clear before .commit
See my answer:
Android Persistent Checkable Menu in Custom Widget After Reboot Android
public abstract SharedPreferences.Editor clear()
Added in API level 1 Mark in the editor to remove all values from the
preferences. Once commit is called, the only remaining preferences
will be any that you have defined in this editor. Note that when
committing back to the preferences, the clear is done first,
regardless of whether you called clear before or after put methods on
this editor.
Returns Returns a reference to the same Editor object, so you can
chain put calls together.
In my user preferences class I was getting a null value on some other strings and my code was something like this:
SharedPreferences sp = Utils.getContext()
.getSharedPreferences(USER_PREFS, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sp.edit();
if (session != null && !"".equals(session)) {
sessionId = session;
editor.putString(SESSION, sessionId).commit();
} else {
sessionId = null;
editor.clear().commit();
}
The editor.clear() was resetting all my other commits!
I don't know why, but it is working by just putting your prefs code inside the async task:
prefss = getSharedPreferences(ACCOUNT_PREFS_NAME, MODE_MULTI_PROCESS);
new AsyncSave(favNamesList).execute();
private static class AsyncSave extends AsyncTask<Void, Void, Boolean> {
String favNamesList;
AsyncSave(String favNamesList) {
this.favNamesList = favNamesList;
}
#Override
protected Boolean doInBackground(Void... params) {
prefss.edit().putString("favNamesList", strings).apply();
return null;
}
}

How to write encrypted app data and decrypte it

I want to store my app data in a file so it could be accessed every time from the app - for example: money, user score, user current sprite...
I have never seen encryption in my life, and I wanted to know if there is an easy way to encrypt data and write it to the phone, and then decrypt it next time the app is open.
If there is no easy way, it would be great if someone could explain how the encryption/decryption works to me.
Use SharedPreferences.
I've used them, and you dont need to encrypt the data.
http://developer.android.com/guide/topics/data/data-storage.html#pref
EXAMPLE(from developer.android):
public class Calc extends Activity {
public static final String PREFS_NAME = "MyPrefsFile";
#Override
protected void onCreate(Bundle state){
super.onCreate(state);
. . .
// Restore preferences
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
boolean silent = settings.getBoolean("silentMode", false);
setSilent(silent);
}
#Override
protected void onStop(){
super.onStop();
// We need an Editor object to make preference changes.
// All objects are from android.context.Context
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editor = settings.edit();
editor.putBoolean("silentMode", mSilentMode);
// Commit the edits!
editor.commit();
}
}

Keep variable value

My application has only one service class (not activity) in which I keep value of one variable that is being dynamically calculated through one method. Then i need to save that value for further comparing.
For example:
class MyClass extends Service{
static int number1;
private void Method(){
int number 2;
/// some calculations for number2 ///
if number2 != number1 { number1 = number2 }
}
I need to compare that variable (number1) to the some other variable (number2) that my application has calculated. This is working well, but when Android OS kills my service, and start that service on some intent (let say after phone reboot) the value of number1 is being lost and I can't use it for comparing.
So how to do it? I thought to write simple TXT file in which one i could keep value of number1 after killing the service,
is there any other way?
the quickest way is to save your variable's value in SharedPreferences and retrieve it for later use.
For example:
public class Calc extends Activity {
public static final String PREFS_NAME = "MyPrefsFile";
#Override
protected void onCreate(Bundle state){
super.onCreate(state);
. . .
// Restore preferences
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
boolean silent = settings.getBoolean("silentMode", false);
setSilent(silent);
}
#Override
protected void onStop(){
super.onStop();
// We need an Editor object to make preference changes.
// All objects are from android.context.Context
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editor = settings.edit();
editor.putBoolean("silentMode", mSilentMode);
// Commit the edits!
editor.commit();
}
}
this code is taken from android developer's page which is for Activity but you may adapt it in your service easily by changing it
You have to save the value to a file or a database as Android users usually monitor services and applications and can close the service
so
persist it in database so later when your service is started you can check the saved value.

How to skip an activity? android

i have a default activity that starts first (Activity A), and from there the user can go to another activity (Activity B). In B after some work the user sets a sharedpreference. the next time the app starts i want to check in A if sharedpreference is null to go to B. and i put this if just under
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
and it encapsulates the whole onCreate. when the app starts it skips A and on B i shows the layout and the FC with NullPointerException.
Any one got experience with this?
OR
any one got a better idea on skipping A?
Well Simon you have to use Shared prefrences. save your data in shared prefrences. Then in the activity where you want to use the data in Shared prefres again get instance of same shared prefrence. get the data and use it.
go through this code
public class Calc extends Activity {
public static final String PREFS_NAME = "MyPrefsFile";
#Override
protected void onCreate(Bundle state){
super.onCreate(state);
. . .
// Restore preferences
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
boolean silent = settings.getBoolean("silentMode", false);
setSilent(silent);
}
#Override
protected void onStop(){
super.onStop();
// We need an Editor object to make preference changes.
// All objects are from android.context.Context
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editor = settings.edit();
editor.putBoolean("silentMode", mSilentMode);
// Commit the edits!
editor.commit();
}
}
probably you will get an insight
To answer my own question. i had a location listener in onDestroy an because it was not initialized because of skipping onCreate it returned NullPointer.

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