如何使用共享的首选项在列表视图中保存切换按钮的状态

Question

I am new in android and facing problem with shared preferences here is what i am trying to do

1. my app contains spinner and list view
2. list view is getting populated by spinner which i successfully build
3. every row of list view contains a single toggle button this will alert dialog or alarm for user on selecting

for saving state of toggle button i am using shared preferences now here i am getting stucked

 final ToggleButton btnlock = (ToggleButton) view.findViewById(R.id.btn);
                    btnlock.setTag(pIndex);
                    btnlock.setOnCheckedChangeListener(new OnCheckedChangeListener(){

                @Override
                public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

                    if(btnlock.isChecked()){

                        btnlock.setButtonDrawable(a_icon);
                        btnlock.setChecked(true); 
                            position = (Integer) buttonView.getTag();

                        sp = getPreferences(MODE_PRIVATE);
                    Editor editor = getSharedPreferences("MyPref", 0).edit();
                    editor.putBoolean("in"+month+"_"+position, true);
                    editor.commit();  

                    }else{
                                                                                               btnlock.setButtonDrawable(a_dicon);
                        btnlock.setChecked(false); 

                         sp = getPreferences(MODE_PRIVATE);
                     Editor editor = getSharedPreferences("MyPref", 0).edit();
                     editor.putBoolean("in"+month+"_"+position, false);              editor.commit();  


                    }

                }


            });

on list i am using this

public View getView(final int index, View view, final ViewGroup parent) {
sp = getSharedPreferences("MY_Pref", 0);
btnlock.setChecked(sp.getBoolean("in"+month+"_"+position,false));

Toast.makeText(getApplicationContext(), "chking"+month+"_"+position+"_"+sp.getBoolean("on"+position ,false),
                   Toast.LENGTH_LONG).show();

}

this toast msg is showing me always false and the position is always a constant why i am getting this and how to solve this?

Answer 1

in the saving part you are loading shared preference file named "MyPref"

 Editor editor = getSharedPreferences("MyPref", 0).edit();

and in the loading part you are loading shared preference file named "MY_Pref"

sp = getSharedPreferences("MY_Pref", 0);

those are two completely different files, which is why you're not seeing your saved key!

to avoid this type of problem in the future, put your file name in a constant

public static final String PREF_FILE = "SomethingSomethingSomething"

and then get your sharedPreferences like this:

SharedPreferences prefs = getSharedPreferences(PREF_FILE,Context.MODE_PRIVATE);

SharedPreferences.Editor editor = getSharedPreferences(PREF_FILE,Context.MODE_PRIVATE).edit();