How to set text in the center of the container in Flutter when trying to reduce container size?

Question

when text container size decrease with font size that time the text not set in center. it is gone below size of container how to solve it.

  Container(
              height: height,
              width: width,
              alignment: Alignment.center,
              decoration: _isSelected
                  ? BoxDecoration(
                color: Colors.transparent,
                border: Border.all(
                  width: 2,
                  color: Colors.black,
                ),
              )
                  : null,

              child: Align(
                alignment: Alignment.center,
                child: Text(
                  _displayText.isEmpty ? 'Enter Text' : _displayText,
                  textAlign: TextAlign.center,
                  overflow: TextOverflow.visible,
                  maxLines: 1,
                  style: TextStyle(
                    color: Colors.black,
                    fontSize: fontSize,
                  ),
                ),
              ),
            ),

Answer 1

Try it with the help of Center() like below:

Container(
          padding: EdgeInsets.all(8.0),
          decoration: _isSelected
              ? BoxDecoration(
            color: Colors.transparent,
            border: Border.all(
              width: 2,
              color: Colors.black,
            ),
          )
              : null,

          child: Center(
            child: Text(
              _displayText.isEmpty ? 'Enter Text' : _displayText,
              textAlign: TextAlign.center,
              overflow: TextOverflow.visible,
              maxLines: 1,
              style: TextStyle(
                color: Colors.black,
                fontSize: fontSize,
              ),
            ),
          ),
        ),

Answer 2

Use the FittedBox widget to automatically scale the text to fit within the container while keeping it centred.

Container(
  height: height,
  width: width,
  alignment: Alignment.center,
  decoration: _isSelected
      ? BoxDecoration(
          color: Colors.transparent,
          border: Border.all(
            width: 2,
            color: Colors.black,
          ),
        )
      : null,
  child: FittedBox(
    fit: BoxFit.scaleDown, // Scale down the text to fit within the container
    alignment: Alignment.center,
    child: Text(
      _displayText.isEmpty ? 'Enter Text' : _displayText,
      textAlign: TextAlign.center,
      style: TextStyle(
        color: Colors.black,
        fontSize: fontSize,
      ),
    ),
  ),
),