TextInputLayoutClearable. When an error is shown, if user starts typing, the error is automatically cleared.

TextInputLayoutClearable.java

package com.lukaspili.mortardemo.ui.custom;

import android.content.Context;
import android.support.annotation.Nullable;
import android.support.design.widget.TextInputLayout;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.AttributeSet;

/**
 * Created by Leonardo on 03/02/2016.
 */
public class TextInputLayoutClearable extends TextInputLayout {

    boolean isTextWatcherSetup;
    TextWatcher textWatcher = 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) {

        }

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

    public TextInputLayoutClearable(Context context) {
        super(context);
    }

    public TextInputLayoutClearable(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public TextInputLayoutClearable(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    @Override
    public void setError(@Nullable CharSequence error) {
        super.setError(error);

        if (!this.isTextWatcherSetup && isErrorEnabled())
            setupTextWatcher();
        else if (this.isTextWatcherSetup && error == null)
            removeTextWatcher();
    }


    private void removeTextWatcher() {
        if (this.getEditText() != null) {
            this.getEditText().removeTextChangedListener(textWatcher);
            this.isTextWatcherSetup = false;
        }
    }

    private void setupTextWatcher() {
        if (this.getEditText() != null) {
            this.getEditText().addTextChangedListener(textWatcher);
            this.isTextWatcherSetup = true;
        }
    }

}