当app force从android中的ram关闭时，我怎样才能检索数据

Question

我正在使用共享首选项来存储数据。每当我关闭并打开应用程序时，它将读取共享的prefs值并保持相同的状态。当我按下时我正确。但是当我从内存中删除应用程序时或强制关闭，共享首选项得到清除。当我重新打开app.how以获取值时，即使我从内存中删除了应用程序，我也得到了空值。

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Conveyer=(SwitchCompat) findViewById(R.id.tubelight);
        fan=(SwitchCompat) findViewById(R.id.Fan);
        ac=(SwitchCompat) findViewById(R.id.AC);
        motor=(SwitchCompat) findViewById(R.id.Motor);

        sharedPreferences = getApplicationContext().getSharedPreferences("MyPrefer", MODE_PRIVATE);
         editor = sharedPreferences.edit();

        A=sharedPreferences.getString("Conveyer","0");
        B=sharedPreferences.getString("fan","0");
        C=sharedPreferences.getString("ac","0");
        D=sharedPreferences.getString("motor","0");

        new fetchingjson().execute();
        if(A=="1"){
            Conveyer.setChecked(true);
        }else{
            Conveyer.setChecked(false);
        }
        if(B=="1"){
            fan.setChecked(true);
        }else{
            fan.setChecked(false);
        }
        if(C=="1"){
            ac.setChecked(true);
        }else{
            ac.setChecked(false);
        }

        if(D=="1"){
            motor.setChecked(true);
        }else{
            motor.setChecked(false);
        }




        Conveyer.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton compoundButton, boolean ischecked) {
                if(ischecked){
                    A="1";
                    Toast.makeText(MainActivity.this, "conveyer is turned on", Toast.LENGTH_SHORT).show();
                }else{
                    A="0";
                    Toast.makeText(MainActivity.this, "conveyer is turned off", Toast.LENGTH_SHORT).show();
                }
                new fetchingjson().execute();

            }
        });
        fan.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton compoundButton, boolean ischecked) {
                if(ischecked){
                    B="1";
                    Toast.makeText(MainActivity.this, "Fan is turned on", Toast.LENGTH_SHORT).show();
                }else{
                    B="0";
                    Toast.makeText(MainActivity.this, "Fan is turned off", Toast.LENGTH_SHORT).show();
                }
                new fetchingjson().execute();
            }
        });
        ac.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton compoundButton, boolean ischecked) {
                if(ischecked){
                    C="1";
                    Toast.makeText(MainActivity.this, "AC is turned on", Toast.LENGTH_SHORT).show();
                }else{
                    C="0";
                    Toast.makeText(MainActivity.this, "AC is turned off", Toast.LENGTH_SHORT).show();
                }
                new fetchingjson().execute();
            }
        });
        motor.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton compoundButton, boolean ischecked) {
                if(ischecked){
                   D="1";
                    Toast.makeText(MainActivity.this, "Motor is turned on", Toast.LENGTH_SHORT).show();
                }else{
                    D="0";
                    Toast.makeText(MainActivity.this, "Motor is turned off", Toast.LENGTH_SHORT).show();
                }
                new fetchingjson().execute();
            }
        });

    }




    private class fetchingjson extends AsyncTask<String,String,String>{

    String url = "http://youwalks.com/get.php?a="+A+"&b="+B+"&c="+C+"&d="+D;

    ProgressDialog dialogProgress = new ProgressDialog(MainActivity.this);
    AndroidHttpClient mmClient = AndroidHttpClient.newInstance("");
    private String response="";
        private  String jstr;
        char phase[];

    @Override
    protected String doInBackground(String... strings) {

        HttpGet request = new HttpGet(url);
        ResponseHandler<String> responseHandler = new BasicResponseHandler();
        try {
            response = mmClient.execute(request, responseHandler);
        } catch (ClientProtocolException exception) {
            exception.printStackTrace();
            return null;
        } catch (IOException exception) {
            exception.printStackTrace();
            return null;
        }
        jstr=""+response;


        if(jstr.equals(null))
        Log.i("url", "" + url);
        Log.i("routes", "" + response);
        return null;
    }

    @Override
    protected void onPreExecute() {
        dialogProgress.setCancelable(true);
        dialogProgress.setMessage("Please wait..");
        dialogProgress.setIndeterminate(false);
        dialogProgress.show();
    }


        @Override
        protected void onPostExecute(String s) {

            dialogProgress.dismiss();
            Log.i("responseeer",""+A);
        }
    }




    @Override
    protected void onResume() {
        super.onResume();

    }

    @Override
    protected void onPause() {
        super.onPause();

        if(fan.isChecked()){
            editor.putString("fan", "1");
            editor.commit();
            Log.i("editor","true");
        }
        else{
            editor.putString("fan", "0");
            editor.commit();
            Log.i("editor","false");
        }
        if(motor.isChecked()){
            editor.putString("motor", "1");
            editor.commit();
            Log.i("editorac","true");
        }
        else{
            editor.putString("motor", "0");
            editor.commit();
            Log.i("editorac","false");
        }
        if(Conveyer.isChecked()){
            editor.putString("Conveyer", "1");
            editor.commit();
            Log.i("editorac","true");
        }
        else{
            editor.putString("Conveyer", "0");
            editor.commit();
            Log.i("editorac","false");
        }if(ac.isChecked()){
            editor.putString("ac", "1");
            editor.commit();
            Log.i("editorac","true");
        }
        else{
            editor.putString("ac", "0");
            editor.commit();
            Log.i("editorac","false");
        }


    }

`