How to color a text in Flutter-CodePudding

I was trying to add color to my Overweight and Underweight with the color red. Could you help me by letting me know how can I do that?

Here is the code:

import 'dart:math';

class CalculatorBrain {
   CalculatorBrain({this.height, this.weight});

  final int height;
  final int weight;

  double _bmi;

  String calculateBMI() {
    _bmi = weight / pow(height / 100, 2);
    return _bmi.toStringAsFixed(1);
  }

  String getResults(){
    if (_bmi >= 25) {
      return 'Overweight';
    } else if (_bmi > 18.5) {
      return 'Normal';
    } else {
      return 'Underweight';
    }
  }

  String getInterpretation () {
    if (_bmi >= 25) {
      return 'You have a higher than normal weight. Try to exercise more.';
    } else if (_bmi > 18.5) {
      return 'You have a normal body weight. Good job!';
    } else {
      return 'You have a lower than normal body weight. You can eat a bit more.';
    }
  }

}

CodePudding user response：

When you declare a Text widget, you can declare also the style of it through the TextStyle class.

Here an example:

Text(
 "Hello world!",
  style: TextStyle(
    color: Colors.red,
  )
)

You can declare other style for text such as fontWeight, textAlign and so on. You can check all on the docs

In your case you can create another function that return the TextStyle or only the text color.

Color getResultColor(){
    if (_bmi >= 25) {
      return Colors.red;
    } else if (_bmi > 18.5) {
      return Colors.black;
    } else {
      return Colors.red;
    }
  }

Finally, your Text would be like:

Text(
 getResults(),
  style: TextStyle(
    color: getResultsColor(),
  )
)

CodePudding user response：

Strings can't have colors by itself in flutter. If you want to add a visible color you can make use of the Text widget. The text widget requires a string and then you can give it some styling too:

return Text(
    getResults(),
    style: TextStyle(
      color: Colors.red,
    ),
  );