How can I get the size of the Text Widget in flutter

Question

I\'ve painted a shape for the background of my content of Text.

I want the background autoscale the Text, even the softWrap being true.

Answer 1

Problem with other answers is that if you use Text widget to display your text and constraint it with measurements result without considering default font family and scale factor, then you will get wrong results because Text widget is using device's textScaleFactor by default and passing it to RichText widget inside of it. This is the correct code to measure text size:

final Size size = (TextPainter(
        text: TextSpan(text: text, style: textStyle),
        maxLines: 1,
        textScaleFactor: MediaQuery.of(context).textScaleFactor,
        textDirection: TextDirection.ltr)
      ..layout())
    .size;