Clear shared preference having dynamic keys-CodePudding

I'm creating a SharedPreferences in my app using a dyanmic key generated using a combination of some fixed String and id(unique id for each item).

Get values from shared preference

public static int getSharedPref(Context context, String keyName) {
    SharedPreferences betaPref = context.getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE);
    return betaPref.getInt("getShare"   keyName, 0);
}

Save value in shared preference

public static void saveSharedPref(Context context, int value, String keyName) {
    try {
        SharedPreferences betaPref = context.getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = betaPref.edit();
        editor.putInt("getShare"   keyName, value);
        editor.apply();
    } catch (Exception e) {
        LogUtil.e("getShare"   keyName, Log.getStackTraceString(e), e);
    }
}

So far it works good, but now I also want to delete these shared preference when user logout from the app.
I know we can use

preferences.edit().remove("getShare").commit();

to remove a particular shared preference, but being a dynamic keys I don't have a exact name to delete it.

Query : Is there any way I can delete all shared preference containing a particular keyword? Or fetch all the keywords used in shared preference and filter them to delete on specific ones

CodePudding user response：

Removing all preferences:

SharedPreferences sharedPreferences  = context.getSharedPreferences("name", Context.MODE_PRIVATE);
sharedPreferences.edit().clear().commit();

Removing single preference:

SharedPreferences sharedPreferences = context.getSharedPreferences("name", Context.MODE_PRIVATE);
sharedPreferences.edit().remove("key_name").commit();

SharedPreferences has the method getAll() that returns a Map<String, ?> . From the Map you can retrieve easily the keys with keySet() and the key/value mappings with entrySet():

Map<String, ?> allEntries = prefA.getAll();
for (Map.Entry<String, ?> entry : allEntries.entrySet()) {
    Log.d("map values", entry.getKey()   ": "   entry.getValue().toString());
}