How to use the TextWatcher class in Android?

Question

Can anyone tell me how to mask the substring in EditText or how to change EditText substring input to password type

Answer 1

For Kotlin use KTX extension function: (It uses TextWatcher as previous answers)

yourEditText.doOnTextChanged { text, start, count, after -> 
        // action which will be invoked when the text is changing
    }

import core-KTX:

implementation "androidx.core:core-ktx:1.2.0"