Passing variables through many activities - java

on MainActivity I have two edit texts which I get name and age values
now I have in this activity for example name="Mohamed" age=26
my questions is how to use these variables freely in other activities without passing them through Intent

Use the Shared Preferences.
Set the values:
SharedPreferences.Editor editor = getSharedPreferences(MY_PREFS_NAME, MODE_PRIVATE).edit();
editor.putString("name", name);
editor.putInt("age", age);
editor.commit();
Retrieve values:
SharedPreferences prefs = getSharedPreferences(MY_PREFS_NAME, MODE_PRIVATE);
String restoredName = prefs.getString("name", null); //null is the default value.
int age = prefs.getInt("age", 0); //0 is the default value.
For more information visit Android Doc Shared Preferences

Related

SharedPreferences editor not executing

In the following piece of code, one of the mEditor lines, doesn't appear to execute.
I've tried many different combinations so far, but can't get it to execute properly. The value is not set at all.
If i try to use the value, like in a Toast, I will receive a ResourcesNotFound Exception
Initialization of SharedPreference in my onCreateView, Fragment
mSharedPreferences = PreferenceManager.getDefaultSharedPreferences(getActivity());
mEditor = mSharedPreferences.edit();
public void onClick(View view) {
int round_number = mSharedPreferences.getInt(getString(R.string.pref_round_played),0);
if (round_number == 0){
game_team.setBackgroundResource(R.drawable.t);
game_team.setVisibility(View.VISIBLE);
knap_bund.setVisibility(View.INVISIBLE);
knap_top.setText("Next Strat");
mEditor.putString(getString(R.string.pref_chosen_team), "T");
mEditor.putInt(getString(R.string.pref_round_played),round_number + 1);
mEditor.apply();
//Show CT side Pistol round here//
}
Following code is used in my onClick, which has other sharedPreferences, working the exact same way, which executes fine.
The first line executes just fine, but the second line containing 'putInt' isn't executing as intended.
mEditor.putString(getString(R.string.pref_chosen_team), "T");
mEditor.putInt(getString(R.string.pref_round_played), 1);
mEditor.apply();
Example of working code:
else if(round_number <= 30){
mEditor.putInt(getString(R.string.pref_round_played),round_number + 1);
mEditor.apply();
}
UPDATE
Just to clarify due to the comments. It's only this one occasion where the sharedPreferences won't work. I use it about 15 other places in this fragment, with no issues at all
I will receive a ResourcesNotFound Exception
I think R.string.pref_round_played is not exist,check it for your strings.xml
you're not posted for your detailed code so do it like this below to save values in shared preference
public static final String PREFS_NAME = "MyPrefsFile";
SharedPreferences.Editor editor = getSharedPreferences(PREFS_NAME , MODE_PRIVATE).edit();
editor.putString("name", "john");
editor.putInt("id", 123);
editor.apply();
Retrieve the data from shared preference
SharedPreferences prefs = getSharedPreferences(MY_PREFS_NAME, MODE_PRIVATE);
String name = prefs.getString("name", ""); // you can put default value if you need
int idName = prefs.getInt("id", 0);
if this is not works for you please post your full code
Update
change your code to this one
mSharedPreferences = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
SharedPreferences.Editor mEditor = mSharedPreferences .edit();

Preferences always returns default value

This code I use to create value in SharedPreference.
SharedPreferences sharedpreferences;
sharedpreferences = getSharedPreferences("user", Context.MODE_PRIVATE);
Editor editor = sharedpreferences.edit();
editor.putInt("ans1",1).commit();
Here is the code to get value from SharedPreference.
SharedPreferences sharedpreferences=getApplicationContext().getSharedPreferences("user", Activity.MODE_PRIVATE);
int ans = sharedpreferences.getInt("ans1",7);
Value of ans always is 7.

Sending Strings between activities

I want to send a value to an activity that HighScore which shows the highest score of the game.
I am saving the score at the game activity in shared preferences, and I am trying to send the score(string value) to the activity HighScore.
Intent i = new Intent(this, HighScoreActivity.class);
i.putExtra("classicHighScore", highScore);
it seems like you are sending your string in an intent.
which means, in your HighScore activity, write
String highScore = getIntent.getStringExtra("classicHighScore", "");
and there you go,
String highScore now has your value,
you can log it to check :
Log.d("HIGH SCORE VALUE ", highScore);
You need to save data in a SharedPreferences object in the first Activity and read it in the other activity.
Saving the score using SharedPreferences in the first Activity:
SharedPreferences preferences = getSharedPreferences("SharedScore", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = preferences.edit();
editor.putInt("classicHighScore", highScore);
editor.commit();
Reading the score from SharedPreference in the other activity:
SharedPreferences preferences = getSharedPreferences("SharedScore", MODE_PRIVATE);
int score = preferences.getInt("classicHighScore", -1);
If you want send a String between activities you must create a Bundle.
Intent i = new Intent(this, HighScoreActivity.class);
Bundle bundle = new Bundle();
bundle.putString("classicHighScore", highScore);
i.putExtra(bundle);
To read de parameter in HighScoreActivity
Bundle arguments = getIntent().getExtras();
String classicHighScore = arguments.getString("classicHighScore");

problem While Sharing text in Android using SharedPreferences

I am Following this link to use the SharedPreferences.Am trying to Apply in my Application but The Shared value returns the null value
Here my code To assign the Shared Variable
SharedPreferences sharedPreferences = getSharedPreferences("pref",Activity.MODE_WORLD_READABLE);
SharedPreferences.Editor editor= sharedPreferences.edit();
String l="hello";
editor.putString(l,"imagepath");
editor.commit();
here code to access the Shared variable
SharedPreferences myPrefs = this.getSharedPreferences("myPrefs", MODE_WORLD_READABLE);
String prefName = myPrefs.getString("imagepath",null);
Toast.makeText(getBaseContext(),"create banner"+prefName,Toast.LENGTH_LONG).show();
here prefName returns null value.It Cannot Shared.
The preference name is "hello", not "imagepath".
String prefName = myPrefs.getString("hello", null);
And I think it's better to use getString("hello", ""). This way, prefName will never be null.
You have written "myPrefs" in (SharedPreferences myPrefs = this.getSharedPreferences("myPrefs", MODE_WORLD_READABLE);)
Change it like this (SharedPreferences myPrefs = this.getSharedPreferences("pref", MODE_WORLD_READABLE);)
here i have change "myPrefs" in ("myPrefs", MODE_WORLD_READABLE) to "pref" .
Now you the coorect one be ("pref", MODE_WORLD_READABLE)
you are using wrong key.
get string like this:
String prefName = myPrefs.getString("hello",null);
you are also using two different sharedPreference name:
SharedPreferences sharedPreferences = getSharedPreferences("pref",Activity.MODE_WORLD_READABLE);
SharedPreferences myPrefs = this.getSharedPreferences("myPrefs", MODE_WORLD_READABLE);
Please make sure you write and read in same SharedPreference.
Your code to write in SharedPreference should look like this:
SharedPreferences sharedPreferences = getSharedPreferences("pref",0);
SharedPreferences.Editor edito r= sharedPreferences.edit();
String l="hello";
editor.putString(l,"imagepath");
editor.commit();
To read from SharedPreference should look like this:
SharedPreferences myPrefs = this.getSharedPreferences("pref", 0);
String prefName = myPrefs.getString("hello",null);
Toast.makeText(getBaseContext(),"create banner"+prefName,Toast.LENGTH_LONG).show();
Switch this around:
editor.putString("imagepath", l);
also you will want to change the possible return value of "null" to a more acceptable error return value, maybe 0 or -1.
String prefName = myPrefs.getString("imagepath","0");
Source Android Doc for Editor:
abstract SharedPreferences.Editor putString(String key, String value)
//Set a String value in the preferences editor, to be written back once commit() or apply() are called.

Load sharedpreferences not giving me a value

Here is my code.
SharedPreferences sharedPreferences = getSharedPreferences(values,
MODE_PRIVATE);
str1 = sharedPreferences.getString("lu121", "test");
str2 = sharedPreferences.getString("lp5151", "test");
et_username.setText(str1);
et_pass.setText(str2);
by default str1 and str2 should have values of test but when i open the android application the edittexts are not set as test instead i see a blank. Is there something wrong with my code?
You need to call commit() to save the values (you didn't include any code where you are writing.
...
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString("lu", "testlu");
editor.putString("lp", "testlp");
editor.commit();

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