Develop Reference

Use getters from SharedPreference Helper Class in Non - Activity Class

I am an android beginner and tried almost every method to use Shared Preferences but when I try to get value in nonactivity class method doesn't work ONLY IF APP REMOVED FROM RECENT APPS.
My Scenario is like:
Class LocationRequestHelper.java
import android.content.Context;
import android.preference.PreferenceManager;
public class LocationRequestHelper {
...
...
public static String getUserId() {
return MainActivity.preferences.getString("userId","");
}
public static void setUserId(String userId) {
MainActivity.preferences.edit().putString("userId", userId ).commit();
}
}
MainActivity
public class MainActivity extends FragmentActivity implements
SharedPreferences.OnSharedPreferenceChangeListener {
public static SharedPreferences preferences;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
preferences = PreferenceManager.getDefaultSharedPreferences(this);
LocationRequestHelper.setUserId("1");
....
....
Utils
public class Utils {
public static void getLocationUpdates(final Context context, final Intent intent, String broadcastevent){
LocationResult result = LocationResult.extractResult(intent);
if (result != null) {
List<Location> locations = result.getLocations();
Location firstLocation = locations.get(0);
accuracy = firstLocation.getAccuracy();
LocationData data = new LocationData();
// MY FUNCTION DOESN'T WORK HERE
data.setUsrid(LocationRequestHelper.getUserId());
updateServer(data);
}
}
getLocationUpdates is called from BroadcastReceiver
Now problems appears after I try to get userID using
LocationRequestHelper.getUserId();
EDITED : Added Broadcast code
LocationUpdatesBroadcastReceiver
public class LocationUpdatesBroadcastReceiver extends BroadcastReceiver {
private static final String TAG = "LUBroadcastReceiver";
public static final String ACTION_PROCESS_UPDATES ="PROCESS_UPDATES";
#Override
public void onReceive(Context context, Intent intent) {
if (intent != null) {
final String action = intent.getAction();
if (ACTION_PROCESS_UPDATES.equals(action)) {
Utils.getLocationUpdates(context,intent,"PROCESS_UPDATES");
}
}
}
}
NOTE:: THIS WORKS FINE IF APP IS IN BACKGROUND. BUT CRASHES AFTER I KILL FROM RECENT APPS.
Please tell me how I can send saved user id in my api call?
sorry for caps but this is main problem :P

The reason the app is crashing is that when it is killed any static variables become null. However you are still trying to access the SharedPreferences from the broadcast receiver and as such are getting a NPE.
The first thing you can do is update your LocationRequestHelper class to accept a context in the method rather than using the static SharedPreferences:
public class LocationRequestHelper {
//...
public static String getUserId(Context context) {
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
return prefs.getString("userId","");
}
public static void setUserId(Context context, String userId) {
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
prefs.edit().putString("userId", userId ).commit();
}
}
Then update you MainActivity to get rid of the SharedPrefs business and change the call to:
LocationRequestHelper.setUserId(this, "1");
And the Utils class to:
data.setUsrid(context, LocationRequestHelper.getUserId());

Shared Preferences not working

I have a problem where my shared preferences are not working in a class file.I am confused and not able to solve it.Below is my file globalfile which saves data as follows.
public class globalfile extends Activity {
SharedPreferences sharedpreferences;
public static final String mypreference = "mypref";
public static final String Pwd = "pwdKey";
public static final String Email = "emailKey";
private static String global_username = "null/", global_pwd = "null/";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
sharedpreferences = getSharedPreferences(mypreference,
Context.MODE_PRIVATE);
}
public String getusername() {
global_username = sharedpreferences.getString(Email, "");
return global_username;
}
public String getuserpwd() {
global_pwd = sharedpreferences.getString(Pwd, "");
return global_pwd;
}
public void setusername(String someVariable) {
global_username = someVariable;
SharedPreferences.Editor editor = sharedpreferences.edit();
editor.putString(Email,global_username);
editor.commit();
}
public void setuserpwd(String someVariable) {
global_pwd = someVariable;
SharedPreferences.Editor editor = sharedpreferences.edit();
editor.putString(Pwd,global_pwd);
editor.commit();
}
}
I first called setuserpwd() & setusername() then getuserpwd() & getusername() from another activity using object of class globalfile.But always returns null.although if I use this code without shared pref.it is working fine

create an instance of Activity with Activity class object
Technically, you can create an instance of an Activity class. but, activity instance would be useless because its underlying Context would not have been set up.
The rule is that you should never ever create instances of Android components (Activity, Service, BroadcastReceiver, Provider) yourself (using the new keyword or other means). These classes should only ever be created by the Android framework, because Android sets up the underlying Context for these objects and also manages the lifecycle.
I think your newly created activity object can't get actual context. so try to avoid your current flow. I suggest you to create a separate class that may use as factory class and I think your problem will solved.
Or another solution would be like this :
Context context = /*get application context*/
SharedPreferences sharedPref = context.getSharedPreferences(
getString(R.string.preference_file_key), Context.MODE_PRIVATE);
/*get value from this sharedPref*/
So you don't need to create activity class object and here you should avoid your previous getter method to get value.

change you globalfile to be a utility class and not an activity so it can be used really easily by other parts of your app (that aren't an activity but have access to an android context).
public class Global {
private final SharedPreferences sharedpreferences;
public static final String mypreference = "mypref";
public static final String Pwd = "pwdKey";
public static final String Email = "emailKey";
private static String global_username = "null/",
global_pwd = "null/";
public Global(Context context) {
this.sharedpreferences = context.getSharedPreferences(mypreference,
Context.MODE_PRIVATE);
}
public String getusername() {
global_username = sharedpreferences.getString(Email, "null/");
return global_username;
}
public String getuserpwd() {
global_pwd = sharedpreferences.getString(Pwd, "null/");
return global_pwd;
}
public void setusername(String someVariable) {
global_username = someVariable;
sharedpreferences.edit().putString(Email,global_username).commit();
}
public void setuserpwd(String someVariable) {
global_pwd = someVariable;
sharedpreferences.edit().putString(Pwd,global_pwd).commit();
}
}
And here's how to use your new util class
Global global = new Global(context);
global.setusername("foo");
Log.d("TAG", "username from prefs = " + global.getusername());
global.setuserpwd("bar");
Log.d("TAG", "password from prefs = " + global.getusername());

How to get values from shared preferences for class by another class

I want to get a string from my shared preference file and use for more classes, but I don't know why not work.
My reader class is:
import android.app.Activity;
import android.content.SharedPreferences;
public class A {
public static String url2;
public void execute() {
String URLPref = "URL";
SharedPreferences prefs = getSharedPreferences("com.exam.search_preferences",Activity.MODE_PRIVATE);
url2 = prefs.getString(URLPref , "");
}
private SharedPreferences getSharedPreferences(String string,
int modePrivate) {
return null;
}
}
And the second class that uses the string
public class SearchHome extends Activity {
static String url2;
A cls2= new A();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.search_activity);
cls2.execute();
url2 = A.url2;
Toast.makeText(getApplicationContext(),"URL:" + url2 ,
Toast.LENGTH_LONG).show();
...
Sorry for my bad english, I never learned.But I'm trying!

You need to pass the Context to your class A, because you can get the SharedPreferences from a Context object. NOTE, an Activity is a Context to some extend
public class A {
public static String url2;
/** #param context used to get the SharedPreferences */
public void execute(Context context) {
String URLPref = "URL";
SharedPreferences prefs = context.getSharedPreferences("com.exam.search_preferences",Activity.MODE_PRIVATE);
url2 = prefs.getString(URLPref , "");
}
}
And then pass the Context to your execute method
public class SearchHome extends Activity {
static String url2;
A cls2= new A();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.search_activity);
// pass context 'this' to the execute function
// This works, because SearchHome extends Activity
cls2.execute(this);
url2 = A.url2;
...

if your data is not confidential it would be a lot easier if you can make a class specially for shared preference and have other activities access it. you will save a lot of time and code will be a lot simpler to follow up
public class HelperShared {
public static final String score = "Score";
public static final String tag_User_Machine = "tag_User_Machine",
tag_Machine_Machine = "tag_Machine_Machine",
tag_Draw_Machine = "tag_Draw_Machine",
tag_Total_Machine = "tag_Total_Machine";
public static SharedPreferences preferences;
public static Editor editor;
public HelperShared(Context context) {
this.preferences = context.getSharedPreferences(score,
Activity.MODE_PRIVATE);
this.editor = preferences.edit();
}
/*
* Getter and Setter methods for Machine
*/
public void setUserMachine(int UserMachine) {
editor.putInt(tag_User_Machine, UserMachine);
editor.commit();
}
public void setMachineMachine(int MachineMachine) {
editor.putInt(tag_Machine_Machine, MachineMachine);
editor.commit();
}
public void setDrawMachine(int DrawMachine) {
editor.putInt(tag_Draw_Machine, DrawMachine);
editor.commit();
}
public void setTotalMachine(int TotalMachine) {
editor.putInt(tag_Total_Machine, TotalMachine);
editor.commit();
}
public int getUserMachine() {
return preferences.getInt(tag_User_Machine, 0);
}
public int getMachineMachine() {
return preferences.getInt(tag_Machine_Machine, 0);
}
public int getDrawMachine() {
return preferences.getInt(tag_Draw_Machine, 0);
}
public int getTotalMachine() {
return preferences.getInt(tag_Total_Machine, 0);
}
}

private SharedPreferences getSharedPreferences(String string,
int modePrivate) {
return null;
}
problem is here.
return null;
you have to return valid SharedPreferences object. otherwise you will always get NullPointerException.

Call this when you want to put a pref:
putPref("myKey", "mystring", getApplicationContext());
Call this when you want to get a pref:
getPref("myKey", getApplicationContext());
You can use SharedPreferences to save any primitive data: booleans, floats, ints, longs, and strings. This data will persist across user sessions (even if your application is killed).
Different Modes:
1 MODE_APPEND
This will append the new preferences with the already exisiting preferences
2 MODE_ENABLE_WRITE_AHEAD_LOGGING
Database open flag. When it is set , it would enable write ahead logging by default
3 MODE_MULTI_PROCESS
This method will check for modification of preferences even if the sharedpreference instance has already been loaded
4 MODE_PRIVATE
By setting this mode , the file can only be accessed using calling application
5 MODE_WORLD_READABLE
This mode allow other application to read the preferences
6 MODE_WORLD_WRITEABLE
This mode allow other application to write the preferences
Read More

You just need to make shared prefrences object in class where you want to have data
SharedPreferences prefrences = getSharedPreferences("my prefs",MODE_PRIVATE)
Editor editor = prefrences.edit();
String s = edit.getString("your key",value);
hope it helps !

Shared Preferences used in OnReceive does not update

I have a service that tracks battery information and stores it in Shared Preferences. Then from my main activity I have BroadcastReceiver(that has OnReceive for listening ACTION_BATTERY_CHANGED)
Every time OnReceive occurs battery level and temperature changes, but my Shared Preferences leaves the same until I change my screen orientation(I think because of recreation of activity).
Please, help me to somehow make onReceive method also update shared preferences.
My Main Activity:
public class MainActivity extends Activity {
protected void onCreate(Bundle savedInstanceState) {
appPrefs = new AppPreferences(getApplicationContext());
}
......
/* Broadcast Receiver for battery stats */
BroadcastReceiver batteryReceiver = new BroadcastReceiver() {
.....
private TextView text;
int level = -1;
#Override
public void onReceive(Context context, Intent intent) {
level = intent.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
text=(TextView) findViewById(R.id.TV_text);
text.setText("level"+level+"something from Shared Pref"+appPrefs.getAnything());
}
}
}
My Shared Preferences:
public class AppPreferences extends PreferenceActivity {
private static final String APP_SHARED_PREFS = "com.aydabtu.BroadcastSMS_preferences"; // Name of the file -.xml
private SharedPreferences appSharedPrefs;
private Editor prefsEditor;
public AppPreferences(Context context)
{
this.appSharedPrefs = context.getSharedPreferences(APP_SHARED_PREFS, Activity.MODE_PRIVATE);
this.prefsEditor = appSharedPrefs.edit();
}
public long getAnything() {
return appSharedPrefs.getLong("Anything", 9);
}
public void setAnything(long a) {
prefsEditor.putLong("Anything", a);
prefsEditor.commit();
}
My service:
BroadcastReceiver batteryLevelReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
......
appPrefs.setAnything(a);
So, why Shared Preferences are not updated as level or temperature in OnReceive method?
And what to do? Any help will be appreciated. :)

Finally, after so much research, I could make it work: just add this:
private Intent starterIntent;
in your class members area above class name, in my example below main class:
public class MainActivity extends Activity {
private Intent starterIntent;
Then anywhere you want place a code to refresh activity without showing to user.:
finish();
starterIntent.setFlags(intent.FLAG_ACTIVITY_NO_ANIMATION);
startActivity(starterIntent);
overridePendingTransition(0,0);

Getting/Setting values SharedPreference globaly

Hi i have a class (MyCustomForm.xml) which i use as a LoginForm for the user.
Now i want to save and load the value from the username(EditText) from the LoginForm using SharedPreferences but i do not know how to set the value of username saved by SharedPreferences into the EditText in LoginForm(MyCustomForm.xml).
I was thinking to save the value in OnPause in my Main.xml and load the value through OnCreate in the class MyCustomForm.xml
Generaly i would like to use SharedPreferences globaly.
How would this look like?
Can somebody please help me to get on the right track?
It was thinking something like this Main.xml:
public class AndroidLogin extends Activity implements OnClickListener {
#Override
protected void onPause() {
super.onPause();
Editor e = mPrefs.edit();
e.putString(USERNM, username);
e.commit();
}
}
Code MyCustomForm (LoginForm):
public class MyCustomForm extends Dialog {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(com.sencide.R.layout.inlogdialog);
EditText userTest = (EditText)findViewById(R.id.txtUserName);
userTest.setText(USERNM);
}
}

You can do something like this :
SharedPreferences settings = PreferenceManager.getDefaultSharedPreferences(YouActivity.this);
String servername = settings.getString("sharedPreferencesKey", "defaultValue");
server.setText(servername); // EditText
And you store data like this :
SharedPreferences.Editor editor = settings.edit();
editor.putString("server", "serverName");
EDIT :
This piece of code should do the trick for you :
SharedPreferences settings = PreferenceManager.getDefaultSharedPreferences(context.getApplicationContext());
String servername = settings.getString("sharedPreferencesKey", "defaultValue");

You need to use the Prefs & Editor
SharedPreferences spOptions;
SharedPreferences.Editor spOptionEditor;
spOptions = getSharedPreferences("yourKey", 0);
spOptionEditor = spOptions.edit();
string username = spOptions.getString("USERNM", null)
null represents the default value if you don't have anything stored yet
You store the data like this:
spOptionEditor.putString("USERNM", txtUsername.getText().toString());
spOptionEditor.commit();

Generally I would recommend you to save the username on a valid login, and not in any lifecycle method.
Then change myForm to this:
public class MyCustomForm extends Dialog {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(com.sencide.R.layout.inlogdialog);
String s = getContext().getSharedPreferences("prefName", Mode.PRIVATE).getString(USERNM);
EditText userTest = (EditText)findViewById(R.id.txtUserName);
userTest.setText(s);
}
}

public void sharedPrefernces() {
sh_Pref = getSharedPreferences("Login Credentials", MODE_PRIVATE);
toEdit = sh_Pref.edit();
toEdit.putString("Username", username);
toEdit.putString("Password", password);
toEdit.commit();
}
Read more: http://mrbool.com/how-to-implement-shared-preferences-in-android/28370#ixzz34ymRp6mN

Just create a file called preferences... and store the value to it using different methods.
Use the methods people have suggested to put and get data from them...
public class Settings extends PreferenceActivity implements
OnSharedPreferenceChangeListener{
public static final String PREFS_PRIVATE = "PREFS_PRIVATE";
public static final String MASTERKEY = "!##$%^&*";
public static final String KEYA = "KEYA";
public static final String KEYB = "KEYB";
public static final String KEYC = "KEYC";
--- the create and get methods for getting and sharing data in the prefs... .....
public static void createPreference(Context context){
getPrefs(context).edit().putString(KEYA, "Default");
getPrefs(context).edit().putInt(KEYB, 0);
getPrefs(context).edit().putLong(KEYC, 0);
getPrefs(context).edit().putBoolean(KEYD, false);
getPrefs(context).edit().commit();
}
public static SharedPreferences getPrefs(Context context) {
return context.getSharedPreferences(PREFS_PRIVATE, 0);
}
public static String getUsername(Context context) {
getPrefs(context).getString(USERNAME, "default");
}
public static void setUsername(Context context, String value) {
getPrefs(context).edit().putString(USERNAME, value).commit();
}
}
..... so on and so forth..... Just implement it if you find any doubt or any thing that you need in more specific please let me know.