Live editing of users input

Question

Is it possible to auto insert characters into an EditText as the user inputs data?

I.e. if the user is entering a long number such as <

Answer 1

For those still facing trouble with backspace and multiple hyphens -

new TextWatcher() 
{
        boolean hyphenExists;

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {
            if (s.length() >= 6 && s.charAt(5) == '-') {
                hyphenExists = true;
            } else {
                hyphenExists = false;
            }

            Log.d("TAG", "beforeTextChanged " + s.toString());
        }

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

            Log.d("TAG", "onTextChanged " + s.toString());
        }

        @Override
        public void afterTextChanged(Editable s) {
            if (s.length() == 5) {
                if (!hyphenExists)
                    s.append('-');
            }
            Log.d("TAG", "afterTextChanged " + s.toString());
        }
    }

Answer 2

This is what I used

private boolean mInEdit;

@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
    if (!mInEdit) {
        mInEdit = true;
        String delimiter = " - ";
        //Remove chars from your delimiter first
        String digits = s.toString().replaceAll("[- ]", "")
                .replaceAll("\\d{4}", "$0" + delimiter);
        //Handle deletion
        int dLength = delimiter.length();
        if (before > count && digits.endsWith(delimiter.charAt(dLength - 1)) {
            digits = digits.substring(0, digits.length() - dLength);
        }
        mCardNumber.setText(digits);
        mCardNumber.setSelection(mCardNumber.length());
        mInEdit = false;
    }
}

Here you replace delimiter with what you want to separate digits.

Answer 3

to solve this issue, i write a class "AutoAddTextWatcher" :

1. Auto insert text into EditText.
2. insert text into EditText at positions you are setted.
3. delete text in EditText at positions you are setted, when text length bigger than 1.

code snippet :

mEditText_birthday.addTextChangedListener(new AutoAddTextWatcher(mEditText_birthday,
            "/",
            new TextWatcher() {},
            4, 6));

AutoAddTextWatcher class

import android.text.Editable;
import android.text.TextWatcher;
import android.widget.EditText;


/**
 * Created by henry.chuang on 2016/5/12.
 */
public class AutoAddTextWatcher implements TextWatcher {
    private CharSequence mBeforeTextChanged;
    private TextWatcher mTextWatcher;
    private int[] mArray_pos;
    private EditText mEditText;
    private String mAppentText;

    public AutoAddTextWatcher(EditText editText, String appendText, int... position){
        this.mEditText = editText;
        this.mAppentText = appendText;
        this.mArray_pos = position.clone();
    }
    public AutoAddTextWatcher(EditText editText, String appendText, TextWatcher textWatcher, int... position){
        this(editText, appendText, position);
        this.mTextWatcher = textWatcher;
    }

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        mBeforeTextChanged = s.toString();

        if(mTextWatcher != null)
            mTextWatcher.beforeTextChanged(s, start, count, after);

    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
        for (int i = 0; i < mArray_pos.length; i++) {
            if(((mBeforeTextChanged.length() - mAppentText.length() * i) == (mArray_pos[i] - 1) &&
                    (s.length() - mAppentText.length() * i) == mArray_pos[i])){
                mEditText.append(mAppentText);

                break;
            }

            if(((mBeforeTextChanged.length() - mAppentText.length() * i) == mArray_pos[i] &&
                    (s.length() - mAppentText.length() * i) == (mArray_pos[i] + 1))){
                int idx_start = mArray_pos[i] + mAppentText.length() * i;
                int idx_end = Math.min(idx_start + mAppentText.length(), s.length());

                String sub = mEditText.getText().toString().substring(idx_start,  idx_end);

                if(!sub.equals(mAppentText)){
                    mEditText.getText().insert(s.length() - 1, mAppentText);
                }

                break;
            }

            if(mAppentText.length() > 1 &&
                    (mBeforeTextChanged.length() - mAppentText.length() * i) == (mArray_pos[i] + mAppentText.length()) &&
                    (s.length() - mAppentText.length() * i) == (mArray_pos[i] + mAppentText.length() - 1)){
                int idx_start = mArray_pos[i] + mAppentText.length() * i;
                int idx_end = Math.min(idx_start + mAppentText.length(), s.length());

                mEditText.getText().delete(idx_start, idx_end);

                break;
            }

        }

        if(mTextWatcher != null)
            mTextWatcher.onTextChanged(s, start, before, count);

    }

    @Override
    public void afterTextChanged(Editable s) {
        if(mTextWatcher != null)
            mTextWatcher.afterTextChanged(s);

    }

}

complete demo source :
https://github.com/henrychuangtw/AutoInsertEditText

Answer 4

@Override
public void afterTextChanged(Editable s) {

    if(s.length() == 3 && len < s.length()){
        s.append(" - ");
    }

}

@Override
public void beforeTextChanged(CharSequence s, int start, int count,
        int after) {
    len = s.length();
}

This will do as well, only this code will insert " - " after 3rd character.

Answer 5

You can achieve this with on text changed

in my case, i have to format input like this : xxx xxx-xxxx

i done as given below:

etMobileNumber.addTextChangedListener(object : TextWatcher {
        override fun afterTextChanged(s: Editable?) {


        }

        override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {
        }

        override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
            if (etMobileNumber.text.length == 3 && count != 0) {
                val text = etMobileNumber.getText().toString() + " "
                etMobileNumber.setText(text)
                etMobileNumber.setSelection(text.length)
            } else if (etMobileNumber.text.length == 7 && count != 0) {
                val text = etMobileNumber.getText().toString() + "-"
                etMobileNumber.setText(text)
                etMobileNumber.setSelection(text.length)
            }
        }
    })

and the result is very dynamic on the go while typing.

input- 1234567890 result - 123 456-7890

Answer 6

By tagging android, I think you are discussing about android editText, is so you can do it by listening the TextChangedListener,

EDITED: for backspace

editText.addTextChangedListener(new TextWatcher() {
            int len=0;
            @Override
            public void afterTextChanged(Editable s) { 
                String str = editText.getText().toString(); 
                 if(str.length()==4&& len <str.length()){//len check for backspace 
                    editText.append("-");
                }
            }

            @Override
            public void beforeTextChanged(CharSequence arg0, int arg1, int arg2, int arg3) {

             String str = editText.getText().toString(); 
              len = str.length();
            }

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


        });