How to touch EditTextPrefences from another activity or another thread

i have a setting Activity that store name , by changing the name it must first send that to my server and if its store in server successfully then it should set in the summary of my EditTextPreference .

everything works fine but at the end i cant touch the EditTextPreference to set name on it.

this method is in setting activity but called from onPostExecute of the AsyncTask

  public void setNewSetting(Activity activity) {
    EditTextPreference editTextPreference = (EditTextPreference) UserSettingActivity.this.findPreference(activity.getString(R.string.pref_name_key));
    name = sharedPreferences.getString(activity.getString(R.string.pref_name_key), "");
    editTextPreference.setSummary(name);
}

the activity is the setting activity that i passed to the AsyncTask and then passed to method.

my problem is here and give me a nullPoiterException for EditTextPreferences

Sorry for my bad english. and thanks in advance.

Method 1:

If activity is still in background, pass your context to AsyncTask and create an instance of your Settings Activity.

SettingsActivity settingsActivity = (SettingsActivity) context;

then, call the method in onPostExecute()

settingsActivity.setNewSetting();

And, have your setNewSetting() method in your SettingsActivity. It should be public and put some checks for null values.

Method 2:

Use an interface delegate. Create an interface:

 public interface TaskListener {
        void onComplete();
    } 

Pass it to AsyncTask when you execute it, something like:

new MyAsyncTask(params, params, new TaskListener() {

    @Override
    public void onComplete () {

        // call setNewSetting from within SettingsActivity
    }

}).execute();

You get it in your AsyncTask constructer:

public MyAsyncTask (String params, String param2, TaskListener taskListenerDelegate) {

    this.taskListenerDelegate = taskListenerDelegate;
}

Call its onComplete() in onPostExecute() :

taskListenerDelegate.onComplete();

Method 3

Not recommended, but you can try with startActivityForResult() too. And, listen in onActivityResult() to apply changes.