label_textfield.dart

Widget _buildTextField(BuildContext context) {
  if (widget.showClearBtn) {
    return Row(
      children: <Widget>[
        Expanded(
          flex: 9,
          child: TextField(
            focusNode: _focusNode,
            style: widget.txtStyle,
            textAlign: TextAlign.left,
            controller: txtController,
            decoration: InputDecoration(
              border: (widget.showBorder) ? UnderlineInputBorder() : InputBorder.none,
              hintText: (isShowHintText) ? widget.hintText : '',
            ),
            onTap: () => _onTap(),
            onChanged: (value) => _onChanged(value),
            onEditingComplete: () => _onComplete(),
          ),
        ),
        (txtController.text.isNotEmpty) ? 
        Expanded(
          flex: 1,
          child: InkWell(
            onTap: () {
              txtController.text = '';
              setState(() {});
            },
            child: Icon(Icons.close, color: Colors.grey,),
          ),
        ) :
        Container()
      ],
    );
  }

  return TextField(
    focusNode: _focusNode,
    style: widget.txtStyle,
    textAlign: TextAlign.left,
    controller: txtController,
    decoration: InputDecoration(
      border: (widget.showBorder) ? UnderlineInputBorder() : InputBorder.none,
      hintText: (isShowHintText) ? widget.hintText : '',
    ),
    onTap: () => _onTap(),
    onChanged: (value) => _onChanged(value),
    onEditingComplete: () => _onComplete(),
  );
}

@override
Widget build(BuildContext context) {
  return Stack(
    children: <Widget>[
      Align(
        alignment: Alignment.bottomLeft,
        child: Text(
          (isShowHintText) ? '' : overlapText,
          textAlign: TextAlign.start,
          style: (txtController.text.isEmpty) ? widget.lblNormalStyle : widget.lblHighlightStyle,
        ),
      ),

      Padding(
        padding: const EdgeInsets.fromLTRB(0, 10, 0, 0),
        child: _buildTextField(context),  
      ),

    ],
  );
}