Android findViewById() in Custom View

View Custmv; private void initViews() {        inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);        Custmv = inflater.inflate(R.layout.id_number_edit_text_custom, this, true);        editText = (EditText) findViewById(R.id.id_number_custom);        loadButton = (ImageButton) findViewById(R.id.load_data_button);        loadButton.setVisibility(RelativeLayout.INVISIBLE);        loadData();    }private void loadData(){        loadButton.setOnClickListener(new OnClickListener() {            @Override            public void onClick(View v) {                EditText firstName = (EditText) Custmv.getParent().findViewById(R.id.display_name);                firstName.setText("Some Text");            }        });    }

try like this.

Change your Method as following and check it will work

private void initViews() {    inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);    inflater.inflate(R.layout.id_number_edit_text_custom, this, true);    View view = (View) inflater.inflate(R.layout.main, null);    editText = (EditText) view.findViewById(R.id.id_number_custom);    loadButton = (ImageButton) view.findViewById(R.id.load_data_button);    loadButton.setVisibility(RelativeLayout.INVISIBLE);    loadData();} 

If it's fixed layout you can do like that:

public void onClick(View v) {   ViewGroup parent = (ViewGroup) IdNumber.this.getParent();   EditText firstName = (EditText) parent.findViewById(R.id.display_name);   firstName.setText("Some Text");}

If you want find the EditText in flexible layout, I will help you later. Hope this help.