I am having troubles using SharedPreferences in an Android app, and I need to get clear on it.
To avoid issues I have created a separated class for all maters regarding SharedPreferences to be used in the app.
This is the class:
public class SharedPreferencesClasMiPaciente {
SharedPreferences prefs;
Context context;
private static String PREFS = "MiPaciente";
public static SharedPreferences getPrefs(Context context){
return context.getSharedPreferences(PREFS,Context.MODE_PRIVATE);
}
public static void insertData(Context context,String key,String value){
SharedPreferences.Editor editor=getPrefs(context).edit();
editor.putString(key,value);
editor.commit();
}
public static void insertDataInt(Context context,String key,Integer value){
SharedPreferences.Editor editor=getPrefs(context).edit();
editor.putInt(key,value);
editor.commit();
}
public static void insertDataLong(Context context,String key,Long value){
SharedPreferences.Editor editor=getPrefs(context).edit();
editor.putLong(key,value);
editor.commit();
}
public static void insertStringSet(Context context,String key,Set<String> value){
getPrefs(context).edit().putStringSet(key,value).commit();
}
public static String retriveData(Context context,String key){
return getPrefs(context).getString(key,"no hay datos");
}
public static int retriveDataInt(Context context,String key){
return getPrefs(context).getInt(key,0);
}
public static long retriveDataLong(Context context,String key){
return getPrefs(context).getLong(key,0);
}
public static Set<String> getStringSet(Context context, String key){
return getPrefs(context).getStringSet(key,null);
}
public static void deleteData(Context context,String key){
SharedPreferences.Editor editor=getPrefs(context).edit();
editor.remove(key);
editor.commit();
}
}
I try to call this class every time I need to get or insert new SharedPreferences Data.
For now, to retrieve data inside a Fragment, I am using this code:
hayFotos = SharedPreferencesClasMiPaciente.retriveDataInt(getContext(),"hayFotos");
To insert data inside a Fragment, I am using this code:
SharedPreferencesClasMiPaciente.insertData(getContext(),"codigo_exploracion_actual",cod_exploracion);
To retrieve data in an Activity, I am using this code:
hayFotos = SharedPreferencesClasMiPaciente.retriveDataInt(this,"hayFotos");
To insert data in an Activity, I am using this code:
SharedPreferencesClasMiPaciente.insertDataInt(getApplicationContext(),"hayFotos",1);
This way is working but not always, there is another fragment where using the same methods, it is getting a different value for the same key:
hayFotos = SharedPreferencesClasMiPaciente.retriveDataInt(getContext(),"hayFotos");
Log.d("test shared","test shared hay fotos "+hayFotos);
At this case I am always getting the value 0 for key "hayFotos".
Is there a way to get SharedPreferences data on all fragments and activities inside an app?
Related
I have been searching for the correct answer everywhere, but couldn't find it anywhere. That is why I am posting this question, this may look very similar to other questions but I didn't find the answer to this yet. I have to retrieve the user data that was saved during the login on Android device and I want to use the same data in a fragment, I tried using several answers found on StackOverflow, none of them worked for me. Look at the code below, how can I get the user values into strings?
SharedPreferences preferences = getActivity().getSharedPreferences("mysharedpref",Context.MODE_PRIVATE);
String user_name = preferences.getString("user_id",null);
String password = preferences.getString("role", null);
I have to pass these string values to a URL, but it doesn't work. I also checked passing values manually, it's working. For example, if I take assign values to the above strings like
String user_name="admin";
String password="administrator";
Best way to use your SharedPrefernce is by using your appContext that is accessible to the whole App(Common SharedPrefernce and accessible Everywhere).
Define your SharedPrefernce instance in your Application class with get and set methods as below : (If you have not created the Application class then create one as below, This class is called at the start of your app)
public class Application extends android.app.Application {
private static Application _instance;
private static SharedPreferences _preferences;
#Override
public void onCreate() {
super.onCreate();
_instance = this;
}
public static Application get() {
return _instance;
}
/**
* Gets shared preferences.
*
* #return the shared preferences
*/
public static SharedPreferences getSharedPreferences() {
if (_preferences == null)
_preferences = PreferenceManager.getDefaultSharedPreferences(_instance);
return _preferences;
}
//set methods
public static void setPreferences(String key, String value) {
getSharedPreferences().edit().putString(key, value).commit();
}
public static void setPreferences(String key, long value) {
getSharedPreferences().edit().putLong(key, value).commit();
}
public static void setPreferences(String key, int value) {
getSharedPreferences().edit().putInt(key, value).commit();
}
public static void setPreferencesBoolean(String key, boolean value) {
getSharedPreferences().edit().putBoolean(key, value).commit();
}
//get methods
public static String getPrefranceData(String key) {
return getSharedPreferences().getString(key, "");
}
public static int getPrefranceDataInt(String key) {
return getSharedPreferences().getInt(key, 0);
}
public static boolean getPrefranceDataBoolean(String key) {
return getSharedPreferences().getBoolean(key, false);
}
public static long getPrefranceDataLong(String interval) {
return getSharedPreferences().getLong(interval, 0);
}
}
Declare the Application class in AndroidManifest.xml file with line android:name=".Application" as shown in below snippet:
<application
android:name=".Application"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:largeHeap="true"
android:supportsRtl="true"
android:theme="#style/AppTheme">
Now, How to store key-value:
Application.setPreferences("Key","String_Value");
How to fetch key-value:
String value_string=Application.getPrefranceData("Key");
You can now set-SharedPrefernce key-value and get-SharedPrefernce value from anywhere in the app using public Application class and the static get and set methods
Firstly create a SharedPreference.java Class.
public class SharedPreference {
Context context;
SharedPreferences sharedPreferences;
String user_name;
String password;
public SharedPreference(Context co) {
context = co;
sharedPreferences = PreferenceManager.getDefaultSharedPreferences(context);
}
public String getPassword() {
password = getStringInput("password");
return password;
}
public void setPassword(String password) {
this.password = password;
stringInput("password", password);
}
public String getUser_name() {
user_name = getStringInput("Username");
return user_name;
}
public void setUser_name(String user_name) {
this.user_name = user_name;
stringInput("Username", user_name);
}
public void stringInput(String key, String value) {
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString(key, value);
editor.commit();
}
public String getStringInput(String key) {
return sharedPreferences.getString(key, "0");
}
}
Now go into activity or Fragment
example: I'm gone use it in MainActivity.java
public class MainActivity extends AppCompatActivity {
Prefrences prefrences;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setTitle("Dashboard");
prefrences = new Prefrences(MainActivity.this);
prefrences.setUser_name("Rishabh Jain");
prefrences.setUser_name("8369554235");
Log.e("Details",prefrences.getUser_name()+" "+prefrences.getPassword())
}
}
The output will be Rishabh Jain 8369554235.
Similarly, you can use this in any Activity or any Fragment
I guess you are trying to get values with different key. Get values with same key you put them with.
String user_name = preferences.getString(preferences.KEY_USERNAME,null);
String password = preferences.getString(preferences.KEY_PASSWORD, null);
----BUT----
And don't use singleton pattern for SharedPreferences it is very bad to use Context in singleton. It will crash your app. You can figure it out why.
Instead use static methods.
public class PreferenceUtil {
public static final String PASSWORD = "PASSWORD";
public static void setInt(Context context, int in, String key) {
SharedPreferences settings;
Editor editor;
settings = context.getSharedPreferences(PREFS_NAME,
Context.MODE_PRIVATE);
editor = settings.edit();
editor.putInt(key, in);
editor.apply();
}
public static int getInt(Context context, String key) {
SharedPreferences settings;
settings = context.getSharedPreferences(PREFS_NAME,
Context.MODE_PRIVATE);
if (settings.contains(key)) {
return settings.getInt(key, 0);
} else
return 0;
}
}
And access it like this
int password = PreferenceUtil.getInt(getActivity(), PreferenceUtil.PASSWORD);
I am passing a jsonobject string value to my shared preferences and commiting it. But while fetching this, its returning the default value.
For putting :
public void new_putMultipleProfileData(String got_multiple_json_data){
Editor editor=app_prefs.edit();
editor.putString(NEW_TESTING_PIC_ID, got_multiple_json_data);
editor.commit();
}
For getting :
public String new_getMultipleProfileData(){
return app_prefs.getString(NEW_TESTING_PIC_ID,"0");
}
Complete Preference Helper Class :
public class PreferenceHelper {
private final String PREF_NAME = "Testing_xyz";
private SharedPreferences app_prefs;
//For Testing
public static final String NEW_TESTING_PIC_ID = "testing";
private Context context;
public PreferenceHelper(Context context) {
app_prefs = context.getSharedPreferences(PREF_NAME,
Context.MODE_PRIVATE);
this.context = context;
}
public void new_putMultipleProfileData(String got_multiple_json_data){
AppLog.Log("new_data_80503","got_multiple_json_data "+got_multiple_json_data);
Editor editor=app_prefs.edit();
editor.putString(NEW_TESTING_PIC_ID, "hello");
editor.commit();
}
public String new_getMultipleProfileData(){
AppLog.Log("new_data_80503","new_getMultipleProfileData "+app_prefs.getString(NEW_TESTING_PIC_ID,"0"));
return app_prefs.getString(NEW_TESTING_PIC_ID,"0");
}
}
If you want to use same preference manager across the app then use defaultSharedPreference. getSharedPreferences return preference file for that context only, it is different for different context.
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
or
you can use ApplicationContext instead of context
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());
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 !
I'm using SharedPreferences in my project with MODE_PRIVATE, when i cleared the app from recent activity list, and opens the app again, all my preference data is cleared.
I'm using this class fro setting and getting preference.
public class Preferences {
private Context _context;
private SharedPreferences _preferences;
private Editor _editor;
private String prefName = "pref";
//=====
public Preferences(Context context){
_context = context;
_preferences = this._context.getSharedPreferences(prefName, Context.MODE_PRIVATE);
_editor = this._preferences.edit();
}
//=====
public Preferences commit(){
_editor.commit();
return this;
}
//=====
public Preferences set(String key, String value){
_editor.putString(key, value);
return this;
}
//=====
public String get(String key){
return _preferences.getString(key, "");
}
//=====
public Preferences set(String key, int value){
_editor.putInt(key, value);
return this;
}
//=====
public int getInt(String key){
return _preferences.getInt(key, 0);
}
//=====
public Preferences setBoolean(String key, boolean value){
_editor.putBoolean(key, value);
return this;
}
//=====
public void removeKey(String key){
_editor.remove(key);
}
//=====
public boolean getBoolean(String key){
return _preferences.getBoolean(key, false);
}
}
can any one help me ...??
change your set method like this
public Preferences set(String key, int value){
_editor.putInt(key, value);
_editor.commit();
return this;
}
you don't need separate commit() into independent method.
good luck
this is another example, in this example i create a value that save my city name and when my app lunched i check for existing , if exist the value of that key returned to me.
SharedPreferences sp;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// define sp
sp=getSharedPreferences("test", Context.MODE_PRIVATE);
// get sp value if exist
if(sp.contains("EkbatanApp")){
String spResult=sp.getString("EkbatanApp", "");
}
}
//save key
public void SaveSettingOnClick(View v){
Editor editor=sp.edit();
editor.putString("EkbatanApp", "Borujerd");
editor.commit();
}