Question 76668 in Flutter Question posted in
The official Flutter documentation can be found here.

How do I display string value from another file? – Flutter

I simplified my code so my question would be easier to ask. Basically, I have a value that goes through an if else statement and then text is printed based on that value.

class Number {

  static void compareVal  () {
    final int a = 5;
      if (a == 1) {
        print('Number is 1');
        //String i = 'Number is 1';
      }
      else {
        print('Number is not 1');
        //String i = 'Number is 1';
      }
    }

}

class RequirementTenWidgetState extends State<RequirementTenWidget>{
  @override
  void initState() {
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
return Scaffold(
      body: Container(
        width: double.infinity,
        height: double.infinity,
        child: const Text('Number',
          style: TextStyle(
            fontSize: 50,
            color: Colors.white,
          ),
          textAlign: TextAlign.center,
        ),
      ),
      floatingActionButton: FloatingActionButton(
        child: Text('something'),
        backgroundColor: Colors.blue[600],
        onPressed: () => {
          Number.caompareVal()
      },

      ),
    );

`

I wanted to add a button that when pressed displays the text on the screen, currently when the button is pressed, the text displays on the terminal and not in the app. How would I get the app to display the text?

Tags:

2

Answers


  1. 0

    For that you have to (1) take one string value which display your text (2) make your number function return type String. (3) Update the string based on that.

    Here is your updated code :

    
class Number {
  static String compareVal() {
    final int a = 5;
    if (a == 1) {
      print('Number is 1');
      return "Number is 1";
    } else {
      print('Number is not 1');
      return "Number is Not 1";
    }
  }
}

class RequirementTenWidgetState extends State<RequirementTenWidget> {
  @override
  void initState() {
    super.initState();
  }

  String stringNumber = "";

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Container(
        width: double.infinity,
        height: double.infinity,
        child: Text(
          "Number",
          style: TextStyle(
            fontSize: 50,
            color: Colors.black,
          ),
          textAlign: TextAlign.center,
        ),
      ),
      floatingActionButton: FloatingActionButton(
        child: Text(stringNumber),
        backgroundColor: Colors.blue[600],
        onPressed: () => {
          setState(() {
            stringNumber = Number.compareVal();
          })
        },
      ),
    );
  }
}
    Login or Signup to reply.
  2. 0

    in-order to show text on the app, use Text() widget

    I am changed the compareVal() return type to String, and kept in the same class for testing, you can use anywhere, just call accordingly

    to update the text in realtime used setState() method

     class _StringDemoState extends State<StringDemo> {

      //method declaration : String is there return type
      String compareVal() {
        final int a = 5;
        if (a == 1) {
          return 'Number is 1';
         
        } else {
          return 'Number is not 1';
          
        }
      }

  //variable result to store and show response from compareVal()
  String result = '';
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Demo')),
      body: Column(

        //Alignments
        mainAxisAlignment: MainAxisAlignment.center,
        crossAxisAlignment: CrossAxisAlignment.stretch,

        //used column to show Text() and Button() in Vertical order
        children: [
          Center(
            //result value will be shown in app,
            // initially '' 
            // once button clicked will update the result
            child: Text(result),
          ),

          MaterialButton(
            child: Text('check'),
            onPressed: () {

              //setState to update values in realtime 
              setState(() {
                
                //return value of compareVal() assigned to result variable, since it is in setState it will be updated immediately 
                result = compareVal();
              });
            },
          )
        ],
      ),
    );
  }
}
    Login or Signup to reply.
Please signup or login to give your own answer.

Back To Top
Search