Android Alphanumeric only, programmatically (NOT XML)

Question

I have a program in Android, with one AutoCompleteTextView named aCTVNumeroPoste.

This AutoCompleteTextView change the type of input depends of other option.

So Option 1 makes the AutoCompleteTextView only Text and Option 2 makes the AutoCompleteTextView only Numbers. And this seems to works well with the keyboard.

But THE PROBLEM is when the AutoCompleteTextView is Text, I only want Alphanumeric, and the keyboard allow me to introduce $%&/()=?¡"!-.,etc.

Heres the code:

if (accion.equals("MANTENIMIENTO")) {
        aCTVNumeroPoste.setInputType(InputType.TYPE_CLASS_TEXT);
        int maxLengthofEditText = 19;
        aCTVNumeroPoste.setFilters(new InputFilter[] {new InputFilter.LengthFilter(maxLengthofEditText)});

    }
    else {
        aCTVNumeroPoste.setInputType(InputType.TYPE_CLASS_NUMBER);
        aCTVNumeroPoste.setKeyListener(DigitsKeyListener.getInstance("0123456789"));
        int maxLengthofEditText = 3;
        aCTVNumeroPoste.setFilters(new InputFilter[] {new InputFilter.LengthFilter(maxLengthofEditText)});
    }

And i want to resolve this Programmatically, not in XML (with android:digits=...).

I tried to use this code, after InputType.TYPE_CLASS_TEXT:

aCTVNumeroPoste.setFilters(new InputFilter[]{
                new InputFilter() {
                    public CharSequence filter(CharSequence src, int start,
                                               int end, Spanned dst, int dstart, int dend) {
                        if (src.equals("")) {
                            return src;
                        }
                        if (src.toString().matches("[a-zA-Z 0-9]+")) {
                            return src;
                        }
                        return "";
                    }
                }
        });

And this one too:

aCTVNumeroPoste.setKeyListener(DigitsKeyListener.getInstance("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 "));

But nothing has worked. Any help is appreciated.

Answer 1

I answer my own question.

From this post How to restrict the EditText to accept only alphanumeric characters

This code works for me:

public static class AlphaNumericInputFilter implements InputFilter {
    public CharSequence filter(CharSequence source, int start, int end,
                               Spanned dest, int dstart, int dend) {

        // Only keep characters that are alphanumeric
        StringBuilder builder = new StringBuilder();
        for (int i = start; i < end; i++) {
            char c = source.charAt(i);
            if (Character.isLetterOrDigit(c)) {
                builder.append(c);
            }
        }

        // If all characters are valid, return null, otherwise only return the filtered characters
        boolean allCharactersValid = (builder.length() == end - start);
        return allCharactersValid ? null : builder.toString();
    }
}

And then add this after InputType.TYPE_CLASS_TEXT:

// Apply the filters to control the input (alphanumeric)
        ArrayList<InputFilter> curInputFilters = new ArrayList<InputFilter>(Arrays.asList(aCTVNumeroPoste.getFilters()));
        curInputFilters.add(0, new AlphaNumericInputFilter());
        curInputFilters.add(1, new InputFilter.LengthFilter(maxLengthofEditText));
        InputFilter[] newInputFilters = curInputFilters.toArray(new InputFilter[curInputFilters.size()]);
        aCTVNumeroPoste.setFilters(newInputFilters);