Set unchangeable some part of editText android

Question

I have some EditText for mobile number input. App must add unique text for every country. For example for Armenia is must add +374 , and user must fill other nu

Answer 1

you can create class extend AppCompatEditText or EditText.

public class CEditTextMaster extends AppCompatEditText {

        private boolean isNeedNoChangeSomeCharacters;
        private String charactersNoChange;

        public CEditTextMaster(Context context) {
            super(context);
            init(context, null);
        }

        public CEditTextMaster(Context context, AttributeSet attrs) {
            super(context, attrs);
            init(context, attrs);
        }

        public CEditTextMaster(Context context, AttributeSet attrs, int defStyleAttr) {
            super(context, attrs, defStyleAttr);
            init(context, attrs);
        }

        public void init(Context context, @Nullable AttributeSet attrs) {

            if (isInEditMode())
                return;

            addTextChangedListener(new TextWatcher() {
                @Override
                public void beforeTextChanged(CharSequence s, int start, int count, int after) {

                }

                @Override
                public void onTextChanged(CharSequence s, int start, int before, int count) {

                }

                @Override
                public void afterTextChanged(Editable s) {
                    if (isNeedNoChangeSomeCharacters && charactersNoChange != null) {
                        if (!getText().toString().startsWith(charactersNoChange)) {
                            removeTextChangedListener(this);
                            if (charactersNoChange.length() > s.length()) {
                                setText(charactersNoChange);
                            } else {
                                setText(charactersNoChange + getText());
                            }
                            setSelection(getText().toString().length());
                            addTextChangedListener(this);
                        }
                    }
                }
            });

        }

        @Override
        protected void onSelectionChanged(int selStart, int selEnd) {
            if (isNeedNoChangeSomeCharacters && charactersNoChange != null) {
                if (length() > charactersNoChange.length() && selStart < charactersNoChange.length()) {
                    setSelection(charactersNoChange.length(),selEnd);
                }
            }
        }


        @Override
        public void setText(CharSequence text, BufferType type) {
            super.setText(text, type);
            if (isNeedNoChangeSomeCharacters && charactersNoChange != null) {
                if (!getText().toString().trim().startsWith(charactersNoChange)) {
                    setText(charactersNoChange + getText());
                }
            }
        }

        public void setCharactersNoChangeInitial(String charactersNoChange) {
            isNeedNoChangeSomeCharacters = true;
            this.charactersNoChange = charactersNoChange;
            if (!getText().toString().trim().startsWith(charactersNoChange)) {
                setText(getText());
            }
        }

}

for use:

edt.setCharactersNoChangeInitial("+734 ");