public class MainActivity extends AppCompatActivity {

    private RecyclerView recyclerView;
    private itemAdapter itemAdapter;
    private RecyclerView.LayoutManager layoutManager;
    Button add_item_btn;
    public static final String myPreferences = "Prefs";
    public static final String TaskKey = "taskKey";
    SharedPreferences sharedPreferences;

    ArrayList<data> myList = new ArrayList<>();

    EditText editText;
    String task;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);

        recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
        itemAdapter = new itemAdapter(myList);
        final LinearLayoutManager layoutManager = new LinearLayoutManager(this);
        layoutManager.setOrientation(LinearLayoutManager.VERTICAL);
        recyclerView.setLayoutManager(layoutManager);
        recyclerView.setAdapter(itemAdapter);


        editText = (EditText) findViewById(R.id.edit_text);

        SharedPreferences sharedPreferences = MainActivity.this.getSharedPreferences(getString(R.string.PREF_FILE), MODE_PRIVATE);
        try {
            myList = (ArrayList) ObjectSerializer.deserialize(sharedPreferences.getString("UserList", ObjectSerializer.serialize(new ArrayList())));
            itemAdapter.notifyData(myList);
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        //  task=sharedPreferences.getString(getString(R.string.TEXT_INFO),"");


//
//  data mLog=new data();
// mLog.setTask(task);
// myList.add(mLog);


        editText.setOnKeyListener(new View.OnKeyListener() {
            public boolean onKey(View v, int keyCode, KeyEvent event) {
                if (event.getAction() == KeyEvent.ACTION_DOWN) {
                    switch (keyCode) {
                        case KeyEvent.KEYCODE_DPAD_CENTER:
                        case KeyEvent.KEYCODE_ENTER:

                            data dataList = new data();

                            task = editText.getText().toString();

                            //       editor.putString(getString(R.string.TEXT_INFO), editText.getText().toString());
                            //   editor.commit();


                            if (task.matches("")) {
                                Toast.makeText(v.getContext(), "Please enter a task", Toast.LENGTH_SHORT).show();
                            }

                            data dataForRecycler = new data();
                            dataForRecycler.setTask(task);
                            myList.add(dataForRecycler);

                            SharedPreferences sharedPreferences = MainActivity.this.getSharedPreferences(getString(R.string.PREF_FILE), MODE_PRIVATE);
                            SharedPreferences.Editor editor = sharedPreferences.edit();

                            try {
                                editor.putString(getString(R.string.TEXT_INFO), ObjectSerializer.serialize(myList));
                            } catch (IOException e) {
                                e.printStackTrace();
                            }
                            editor.commit();


                            itemAdapter.notifyData(myList);
                            editText.setText(null);
                            editText.setVisibility(View.GONE);
                            //   InputMethodManager inputManager = (InputMethodManager)
                            //           getSystemService(Context.INPUT_METHOD_SERVICE);
                            //  inputManager.hideSoftInputFromWindow((null == getCurrentFocus()) ? null : getCurrentFocus().getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);
                            InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
                            imm.hideSoftInputFromWindow(v.getWindowToken(), 0);


                            return true;
                        default:
                            break;
                    }
                }
                return false;
            }
        });


        add_item_btn = (Button) findViewById(R.id.add_item_button);
        add_item_btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                editText.setVisibility(View.VISIBLE);
                editText.requestFocus();
                InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
                imm.toggleSoftInput(InputMethodManager.SHOW_FORCED, 0);

            }
        });
    }


}

public class data implements Serializable {
    private String task;
    private boolean isChecked;
    RecyclerView info;

//Default Constructor
    public data()
    {}

    //overloaded constructor

  public data (String task, boolean isChecked)
  {
      this.task=task;
      this.isChecked=isChecked;
  }

    //getter to return value of String variable task
    public String getTask()
    {return task;}

    //getter to return value of boolean isChecked

    public boolean isChecked()
    {return isChecked;}

    //setter for string variable task
    public void setTask(String task)
    {
        this.task=task;
    }

    //setter for boolean isChecked
    public void setChecked(boolean isChecked)
    {
        this.isChecked=isChecked;
    }
}

public class itemAdapter extends RecyclerView.Adapter<itemAdapter.RecyclerItemViewHolder>  {
    private ArrayList<data> myList;
    int mLastPosition = 0;

    public itemAdapter(ArrayList<data> myList) {
        this.myList = myList;

   }
    public RecyclerItemViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item, parent, false);
        RecyclerItemViewHolder holder = new RecyclerItemViewHolder(view);
        return holder;
    }
    @Override
    public void onBindViewHolder(RecyclerItemViewHolder holder, final int position) {
        Log.d("onBindViewHoler ", myList.size() + "");
        holder.etTaskTextView.setText(myList.get(position).getTask());
        mLastPosition =position;
    }
    @Override
    public int getItemCount() {
        return(null != myList?myList.size():0);
    }
    public void notifyData(ArrayList<data> myList) {
        Log.d("notifyData ", myList.size() + "");
        this.myList = myList;
        notifyDataSetChanged();
    }
    public class RecyclerItemViewHolder extends RecyclerView.ViewHolder {
        private final TextView etTaskTextView;

        private LinearLayout mainLayout;
        public RecyclerItemViewHolder(final View parent) {
            super(parent);
            etTaskTextView = (TextView) parent.findViewById(R.id.task_text);

            mainLayout = (LinearLayout) parent.findViewById(R.id.list_linear_layout);
            mainLayout.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Toast.makeText(itemView.getContext(), "Position:" + Integer.toString(getPosition()), Toast.LENGTH_SHORT).show();
                }
            });

        }
    }
}

public class ObjectSerializer  {

    public static String serialize(Serializable obj) throws IOException {
        if (obj == null) return "";
        ByteArrayOutputStream serialObj = new ByteArrayOutputStream();
        ObjectOutputStream objStream = new ObjectOutputStream(serialObj);
        objStream.writeObject(obj);
        objStream.close();
        return encodeBytes(serialObj.toByteArray());
    }

    public static Object deserialize(String str) throws IOException, ClassNotFoundException {
        if (str == null || str.length() == 0) return null;
        ByteArrayInputStream serialObj = new ByteArrayInputStream(decodeBytes(str));
        ObjectInputStream objStream = new ObjectInputStream(serialObj);
        return objStream.readObject();
    }

    public static String encodeBytes(byte[] bytes) {
        StringBuffer strBuf = new StringBuffer();

        for (int i = 0; i < bytes.length; i++) {
            strBuf.append((char) (((bytes[i] >> 4) & 0xF) + ((int) 'a')));
            strBuf.append((char) (((bytes[i]) & 0xF) + ((int) 'a')));
        }

        return strBuf.toString();
    }

    public static byte[] decodeBytes(String str) {
        byte[] bytes = new byte[str.length() / 2];
        for (int i = 0; i < str.length(); i+=2) {
            char c = str.charAt(i);
            bytes[i/2] = (byte) ((c - 'a') << 4);
            c = str.charAt(i+1);
            bytes[i/2] += (c - 'a');
        }
        return bytes;
    }
}