To obtain shared preferences, use the following method
In your activity:
SharedPreferences prefs = this.getSharedPreferences(
"com.example.app", Context.MODE_PRIVATE);
To read preferences:
String dateTimeKey = "com.example.app.datetime";
// use a default value using new Date()
long l = prefs.getLong(dateTimeKey, new Date().getTime());
To edit and save preferences
Date dt = getSomeDate();
prefs.edit().putLong(dateTimeKey, dt.getTime()).apply();
The android sdk's sample directory contains an example of retrieving and storing shared preferences. Its located in the:
<android-sdk-home>/samples/android-<platformversion>/ApiDemos directory
Edit==>
I noticed, it is important to write difference between commit()
and apply()
here as well.
commit()
return true
if value saved successfully otherwise false
. It save values to SharedPreferences synchronously.
apply()
was added in 2.3 and doesn't return any value either on success or failure. It saves values to SharedPreferences immediately but starts an asynchronous commit.
More detail is here.
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