Android how to focus another edittext when click backspace

Question

I am trying to make Pin entering page and I created 4 EditTexts and I created a function which is below in my activity. My problem is when i click backspace button I want to focus Current EditText to Before(Back) EditText but Key listener not works.

the logic is simple, when user enters a number to edittext, it losts focus and next edittext is getting focus then it goes like that. but the problem is when I click back space I want to go back before edittext to enter number again. I tried to insert keyListener inside of beforeTextChange but it is not worked.

 private void SetTextChange(final EditText etCurrent, final EditText etForward,final EditText etBack, final boolean isLast, final int currentPosition)
{

    etCurrent.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) {

            if (etCurrent.getText().length() == 1 && !isLast ) {
                etCurrent.setTypeface(null, Typeface.NORMAL);
                etCurrent.clearFocus();
                etForward.requestFocus();
                etForward.setCursorVisible(true);

                etCurrent.getBackground().setColorFilter(getResources().getColor(R.color.lavender_indigo), PorterDuff.Mode.SRC_ATOP);
            } else if (etCurrent.length() == 0) {
                etCurrent.getBackground().setColorFilter(getResources().getColor(R.color.french_gray), PorterDuff.Mode.SRC_ATOP);
                etCurrent.setTypeface(null, Typeface.SANS_SERIF.getStyle());

                etCurrent.setTypeface(null, Typeface.NORMAL);
                etCurrent.clearFocus();
                etBack.requestFocus();
                etBack.setCursorVisible(true);

            }


            if (etCurrent.length() != 0) {
                Integer currentKey = Integer.parseInt(etCurrent.getText().toString());
                keyList.set(currentPosition, currentKey);
            } else
                keyList.set(currentPosition, -1);

            if (keyList.size() > 3)
                showToast(keyList.get(0) + " " + keyList.get(1) + " " + keyList.get(2) + " " + keyList.get(3));

        }

        @Override
        public void afterTextChanged(Editable s) {

        }
    });

    /*curText.setOnFocusChangeListener(new View.OnFocusChangeListener() {
        public void onFocusChange(View arg0, boolean arg1) {
            curText = etCurrent;
            backText = etBack;
            curText.setText("");
        }

        });*/
    }

This is also one of my EditText sample xml.(Others are the same)

  <EditText
        android:layout_column="1"
        android:layout_columnWeight="1"
        android:id="@+id/etActivationDigit1"
        android:layout_width="70dp"
        android:layout_height="wrap_content"
        android:textSize="80dp"
        android:textAlignment="center"
        android:gravity="center_horizontal"
        android:hint="*"
        android:textColorHint="@color/french_gray"
        android:backgroundTint="@color/french_gray"
        android:fontFamily="sans-serif"
        android:textColor="@color/perfume"
        android:maxLength="1"
        android:inputType="number"
         />

I just wanted to erase and focus back when user enters wrong number. Attention : when you fill all fields you will see you can delete and go back but I want to go back middle of pin code. Thank you.

  etCurrent.setOnKeyListener(new View.OnKeyListener() {
        @Override
        public boolean onKey(View v, int keyCode, KeyEvent event) {

            if(etCurrent.getText().toString() == "" && keyCode == event.KEYCODE_DEL)
            {
                etCurrent.setText("");
                etCurrent.clearFocus();
                etBack.requestFocus();
                etBack.setText("");
            }
            return false;
        }
    });

My Backspace listener not triggers when I touch backspace but it triggers all other characters.

Answer 1

This is what worked for my 4-digit pin code activity.

private void setupInputListeners() {
    verificationCode1EditText.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) {
            if (s.length() == 1) {
                verificationCode2EditText.requestFocus(View.FOCUS_DOWN);
            }
        }

        @Override
        public void afterTextChanged(Editable s) {
        }
    });

    verificationCode2EditText.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) {
            if(count == 0) {
                verificationCode1EditText.requestFocus(View.FOCUS_DOWN);
            } else {
                if (s.length() == 1) {
                    verificationCode3EditText.requestFocus(View.FOCUS_DOWN);
                }
            }
        }

        @Override
        public void afterTextChanged(Editable s) {
        }
    });

    verificationCode3EditText.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) {
            if(count == 0) {
                verificationCode2EditText.requestFocus(View.FOCUS_DOWN);
            } else {
                if (s.length() == 1) {
                    verificationCode4EditText.requestFocus(View.FOCUS_DOWN);
                }
            }
        }

        @Override
        public void afterTextChanged(Editable s) {
        }
    });

    verificationCode4EditText.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) {
            if(count == 0) {
                verificationCode3EditText.requestFocus(View.FOCUS_DOWN);
            }
        }

        @Override
        public void afterTextChanged(Editable s) {
        }
    });
}

Answer 2

just add this code in your editText onTextChanged method

@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
if(yourEditText.length()==0){
                priviousEditText.requestFocus();
            }
}