EditTextAlphabet

If you don't want to allow users to enter digits and special character into edittext using mobile keyboard then you can use this code.

How to make EditText accepts only Alphabet(No digits or Special Characters)?

I made AlphabetsSymbolsInputFilter class which you can use with your EditText. Even you can specify special characters which you want to allow from user.

class AlphabetsSymbolsInputFilter(symbols: String) : InputFilter {

        private var mWordPattern: String
        var mLetterPattern: String

        init {
            mLetterPattern = "[a-zA-Z.$symbols ]"
            //mLetterPattern = "[a-zA-Z0-9.$symbols ]" // replace if alphanumeric
            mWordPattern = "$mLetterPattern+"
        }

        override fun filter(
            source: CharSequence,
            start: Int,
            end: Int,
            dest: Spanned,
            dstart: Int,
            dend: Int
        ): CharSequence? {
            if (source == "") {
                println("In backspace")
                return source
            }
            if (source.isNotEmpty() && source.toString().matches(mWordPattern.toRegex())) {
                return source
            }
            var sourceStr = ""
            if (source.isNotEmpty() && !source.toString().matches(mLetterPattern.toRegex())) {
                sourceStr = source.toString()
                while (sourceStr.isNotEmpty() && !sourceStr.matches(mWordPattern.toRegex())) {
                    println(" source --> $source dest ---> $dest")
                    if (sourceStr.last().isDigit()) {
                        print("Is digit ")
                        sourceStr = sourceStr.subSequence(0, sourceStr.length - 1).toString()
                    } else if (!sourceStr.last().toString().matches(mLetterPattern.toRegex())) {
                        print("Is emoji or weird symbols")
                        sourceStr = sourceStr.subSequence(0, sourceStr.length - 1).toString()
                    } else
                        break
                }
                return sourceStr
            }
            return source
        }
    }

Use below function with EditText filter.

  fun editTextAllowAlphabetsSymbols(symbols: String): Array<InputFilter> {
        return arrayOf(AlphabetsSymbolsInputFilter(symbols))
    }

How to use AlphabetsSymbolsInputFilter with EditText?

Just need to call editTextAllowAlphabetsSymbols() function with EditText's Filter Property.

  editTextName.filters = editTextAllowAlphabetsSymbols("")

If you want to allow user to use special character like '$' than you can do like below.

 editTextName.filters = editTextAllowAlphabetsSymbols("$")

Where to use AlphabetsSymbolsInputFilter class?

You can use when taking user input for

• Name, First Name and Last Name
• Birthplace
• State or any places when you don't want to allow user to add digit and special characters.

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