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editor.remove() in sharedpreferences not removing the key

I have experienced a strange behavior that does not make any sense to me.
I have managed to save a value of temperature in sharedpreferences in a Java Class that is not an activity by doing this:
The method getContextOfApplication() is the one I am using in my Java.Class where i am putting the value of a temperature in a String and storing it in sharedpreferences as "temperature".
This method is declared in my MainActivity like this:
public static Context contextOfApplication;
public static Context getContextOfApplication() {
return contextOfApplication;
}
This method getContextOfApplication(); is the used in all assosiacions with sharedpreferences, in Mainactivity and in my Java.Class
tempParsed = Jobject.get(("temp")) + "";
SharedPreferences tempSettings = getSharedPreferences(getContextOfApplication());
SharedPreferences.Editor tempEdit = tempSettings.edit();
tempEdit.putString("temperature", tempParsed);
tempEdit.apply();
And later I recieve this value of the key "temperature" in my MainActivity like this:
SharedPreferences fetchSettings =
PreferenceManager.getDefaultSharedPreferences(getContextOfApplication());
String Temp = fetchSettings.getString("temperature", "");
And I can use the stored temperaure with the String Temp.
So far so good.
Later on in my code I wanted to delete this string in that is saved in sharedpreferences with the key "temperature".
Easy I thought...
First I called this code when I wanted to delete the value / values
SharedPreferences fetchSettings =
PreferenceManager.getDefaultSharedPreferences(getContextOfApplication());
SharedPreferences.Editor editor = fetchSettings.edit();
editor.clear();
editor.apply();
But this code deletes ALL information that is stored, so I obvously didn't want that.
That's why I tried to change this line:
editor.clear();
editor.apply();
To this:
editor.remove("temperature")
editor.apply();
But this didn't work!!
Now you are probably wondering "Are you sure that is what your key is named?"
I added this code to read all entries that were stored in the defaultsharedpreferences:
Map<String, ?> allEntries = fetchSettings.getAll();
for (Map.Entry<String, ?> entry : allEntries.entrySet()) {
Log.d("mapvalues ", entry.getKey() + ": " + entry.getValue().toString());
}
AND THE LOG SHOWS "temperature:" as the key....
Why is editor.clear(); working but editor.remove("key") is not?

According to the docs you need to call commit for the changes to happen:
editor.remove("temperature").commit();

Solved
You can try this code for remove single preference:
Prefs.remove("my_custom_key");
Don't forget to import library:
import com.pixplicity.easyprefs.library.Prefs;
This code worked for me Beautifully.

fetch integer value from sharedpreference

I use the following helper to save user input to sharedpreference:
protected void storeData(SharedPreferences.Editor editor,
String key, EditText et) {
String content = et.getText().toString();
if ("".equals(content)||" ".equals(content)) {
editor.remove(key);
} else {
editor.putString(key, content);
}
}
then
number1 = (EditText)findViewById(R.id.number1);
SharedPreferences sharedPreferences = getSharedPreferences("Database", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
storeData(editor,"number1", number1);
editor.commit();
I wish to ask if how can I retrieve that value as a integer, then use it for some calculation.
I been searching and found this , found that they use editor.putInt(key,content);
But is that possible to extract the value as integer straight from my method?
thank you.

Your storeData() method is setting a string (putString()). Shared prefs store typed values distinctly different. That is, you cannot put "1" as a string then get it our later as an integer.
You need to use put/getInt() consistently. Alternatively you could store it as a string, and again consistently get it as a string and coerce it to an int as you need.

Your really should be using putInt(), but you can also use Integer.parseInt("some string") to convert your String value to an integer.

Use editor.commit() inside the else part
A suggestion:
use editor.apply() instead of editor.commit() as commit handles the job in foreground whereas apply handles that asynchronously.

I know, the question has been asked long time agao. I came up with similar situation. So, the might help someone in the future.
//for integer values
port = (EditText) findViewById(R.id.devicePort);
int devicePort = Integer.parseInt(port.getText().toString());
editor.putInt(getString(R.string.devicePort), devicePort);
editor.apply();

Increment shared preference key after adding value

In my app, the user can add a name and an age for multiple people. Most likely it will only be around 2 or 3. I want to store these in shared preferences. I set a counter to keep track of how many people have been stored as well as to manage which key goes with which value. I took the edittext input and put it in a string and then put it into the shared preferences like so, adding on the counter so I know that is the first person and would access the person with "name1".
//this is in the class
public int count = 1;
//this is in the main
SharedPreferences sharedPreferences = getSharedPreferences("registerData", Context.MODE_PRIVATE);
SharedPreferences.Editor myEditor = sharedPreferences.edit();
myEditor.putString("Name"+count, name);
myEditor.putString("Age"+count, age);
Unless I am mistaken, that should put the string "name" into "Name1".
Then I go and try to access it in another activity with...
SharedPreferences sharedPreferences = getSharedPreferences("registerData", Context.MODE_PRIVATE);
String name = sharedPreferences.getString("Name"+count,"");
String age = sharedPreferences.getString("Age"+count,"");
Then i would update the counter before the next person would be added to change the key to "Name2" "Age2", and so on.
Whenever I try to set the strings to a textview, they show up blank. Which means its not the same String to access the key. The putString has to get the "Name1", because even when I try to access the getString("Name",""), it's still blank. Is there something I'm doing wrong or missing. Or there is a better way of doing this? Thanks.

SharedPreferences sharedPreferences = getSharedPreferences("registerData",Context.MODE_PRIVATE);
SharedPreferences.Editor myEditor = sharedPreferences.edit();
myEditor.putString("Name"+count, name);
myEditor.putString("Age"+count, age);
myEditor.apply();//returns nothing,don't forgot to commit changes
also you can use
myEditor.commit() //returns true if the save works, false otherwise.

Is there something I'm doing wrong or missing. Or there is a better
way of doing this?
If SharedPreferences key names are dynamic then you should use SharedPreferences.getAll() which return all keys available in selected preference:
Map<String, ?> allKeys = sharedPreferences.getAll();
Now iterate through allKeys to check key names and get values from Map.Entry related to key like:
for (Map.Entry<String, ?> entry : allKeys.entrySet()) {
Log.v("TAG","Key Name :" entry.getKey());
Log.v("TAG","Key Value :" entry.getValue());
}

You have to call apply() on the shared preference editor after making changes.
...
myEditor.apply();
Shared preferences however, are not meant to store content related data. Consider using more appropriate solutions like a database.

How to avoid adding duplicate values in shared preferences in android?

In android, i am adding string values using shared preferences, but i want to compare the value which i am going to add to shared preferences with values which are already stored in shared preferences to avoid adding duplicate values, but i am not getting how to do this?
or is there any alternate method to avoid adding duplicate values in shared preferences?
I am adding string values using following code
sharedpreferences = getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);
Editor editor = sharedpreferences.edit();
editor.putString(Name, s);
editor.commit();

In android you cannot really have duplicate value in sharedPreference because every time you change or modify a value on sharedPreference it will replace the previous with the current. So since every instance of it has a single unique key, which mean it will always be unique (in my experience every time i messed up with this keys like giving the same name key for both an Int and boolean for example i end up crashing the app or having some kind of exception)
If im wrong i hope someone else will correct me and provide you with a better answer!

I don't know whether I'm understanding your question quite well or not, but Android's SharedPreferenceshas it's own contains to check if a a key already exists or not.
sharedpreferences = getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);
if (sharedpreferences.contains(NAME)) //It already contains NAME key
On the other hand, if your worries are about a single key's value not to be repeated, just read it before storing the new value and compare themselves, no more.
sharedpreferences = getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);
if (!sharedpreferences.getString(NAME, "").equals(s)) {
// It does not have the same value, store 's'
sharedpreferences
.edit();
.putString(NAME, s);
.commit();
}
However, in this particular case I wouldn't perform this verification, just overwrite the value and that's it, as it always gonna be the same.

First get String value from SharedPreferences as oldvalue then compare with newvalue which you want to store. If String not match then save newvalue in SharedPreferences.
Try something like this
String str_newvalue = "new string here";
SharedPreferences sharedpref = this.getSharedPreferences(this.getPackageName(), context.MODE_PRIVATE);
String str_oldvalue = sharedpref.getString("key", "");
if (!str_newvalue.equals(str_oldvalue)) {
sharedpref.edit().putString("key", str_newvalue).commit();
}

Do this
SharedPreferences prefs = getPreferences(MODE_PRIVATE);
String restoredText = prefs.getString("text", null);
if(restoredText.matches(your string))
{
// do nothing
}
else
{
//save your data
}
}

SharedPreferences dont save

my problem: When I want to save a sharedPreference and restart the app, it doesnt load the right value..
My code:
int punkteint = 0;
TextView test1;
String points;
private static String SHARED_PREF_ID = "0";
public void onCreate(Bundle savedInstanceState) {
test1 = (TextView) findViewById(R.id.test1);
SharedPreferences load = getSharedPreferences(SHARED_PREF_ID, 0);
points = load.getString("punkte", "0");
points = SHARED_PREF_ID;
test1.setText(points);
mehrPunkte();
}
public void mehrPunkte() {
punkteint++;
SHARED_PREF_ID = Integer.toString(punkteint);
SharedPreferences load = getSharedPreferences(SHARED_PREF_ID, MODE_PRIVATE);
points = load.getString("punkte", "0");
points = SHARED_PREF_ID;
test1.setText(points);
SharedPreferences save = getSharedPreferences(SHARED_PREF_ID, MODE_PRIVATE);
save.edit().putString("punkte", SHARED_PREF_ID).commit();
}
What did I do wrong here?
Hope you can help me

Not sure what you're trying to do here:
points = load.getString("punkte", "0");
points = SHARED_PREF_ID;
test1.setText(points);
Basically, what you've told it to do is "load punkte's value into points, then load SHARED_PREF_ID into points". That means points will always be equal to SHARED_PREF_ID here. Remove the lines that say "points = SHARED_PREF_ID;" and you will probably have more success.
Additionally, I would not change SHARED_PREF_ID's value. Make it a final String and give it some unique value (like "punkte_prefs").
Lastly, I would take a look at the documentation which has great examples, and #Kaediil's answer as well (as he caught something I missed...).

This line:
save.edit().putString("punkte", SHARED_PREF_ID).commit();
is saving SHARED_PREF_ID as the value of punkte. So, it will always be 0. Maybe you mean:
save.edit().putString("punkte", String.valueOf(punkteint)).commit();
or maybe:
save.edit().putString("punkte", String.valueOf(points)).commit();
I am not sure what you are trying to actually save.
Oh and you are resettiong the value as soonas you get it from the shared prefs:
points = load.getString("punkte", "0");
points = SHARED_PREF_ID;
Don't do the second line.

Not sure. What your doing should work but I would use this instead
SharedPreferences.Editor prefEditor = save.edit();
prefEditor.putString("blah", blah);
PredEditor.commit()
Do the save in onPause and load in onResume. Could help if the data is meant to change thrpught the activity.

I think you've gotten yourself all twisted up here.
private static String SHARED_PREF_ID = "0";
...
SharedPreferences load = getSharedPreferences(SHARED_PREF_ID, 0);
points = load.getString("punkte", "0");
points = SHARED_PREF_ID;
These lines read shared preferences from a file named "0". Is that what you wanted? That's a not-very-useful name for a file. The next line reads a string value named "punkte" into the variable "points" and then immediately discards that value and replaces it with "0".
punkteint++;
SHARED_PREF_ID = Integer.toString(punkteint);
SharedPreferences load = getSharedPreferences(SHARED_PREF_ID, MODE_PRIVATE);
These lines increment a counter, use it to generate a whole new filename, and loads a whole new set of preferences from that file. Again, you load "points" from those preferences and immediately discard the value, setting it to this new filename.
SharedPreferences save = getSharedPreferences(SHARED_PREF_ID, MODE_PRIVATE);
save.edit().putString("punkte", SHARED_PREF_ID).commit();
These lines re-load the preferences from that new file again and writes the filename into the "punkte" value.
It looks like you're deliberately generating a series of preferences files, each of which contains its own name under the value "punkte".
When you next run the app, you'll go back to reading preferences from file "0", getting the same value you got the first time: "0"
It would help if you told us what you were actually trying to do.