Question 75436 in Flutter Question posted in
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How should I use const in the grammar below? – Flutter

I’m studying platters by myself. When I enter the code like below, it says to use const grammar like the attached picture, how can I add it without errors?

enter image description here


class MyHomePage extends StatelessWidget {
  final String title; //
  MyHomePage({required this.title});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(
          title,
        ),
      ),
      body: Center(
        // child: Image.asset('images/tree.jpg'),
        child: Text(
          'Hello, Text Widget',
          style: TextStyle(
            fontSize: 25,
            color: Colors.purple,
          ),
        ),
      ),
    );
  }
}

Please give me answer bro…
I’m begginner

Tags:

3

Answers


  1. 0

    It is just warring/suggestion message for better practice , you can add const before center

    body: const Center(
  // child: Image.asset('images/tree.jpg'),
  child: Text(
    'Hello, Text Widget',
    style: TextStyle(
      fontSize: 25,
      color: Colors.purple,
    ),
  ),
),

    But if you read something inside the Center widget, it cant be const.

    Find more about dart.

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  2. 0

    do this way,

    class MyHomePage extends StatelessWidget {
  final String title; //
  MyHomePage({required this.title});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(
          title,
        ),
      ),
      body: const Center(
        // child: Image.asset('images/tree.jpg'),
        child: Text(
          'Hello, Text Widget',
          style: TextStyle(
            fontSize: 25,
            color: Colors.purple,
          ),
        ),
      ),
    );
  }
}

    or

    class MyHomePage extends StatelessWidget {
  final String title; //
  MyHomePage({required this.title});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(
          title,
        ),
      ),
      body: Center(
        // child: Image.asset('images/tree.jpg'),
        child: const Text(
          'Hello, Text Widget',
          style: TextStyle(
            fontSize: 25,
            color: Colors.purple,
          ),
        ),
      ),
    );
  }
}
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  3. 0

    It is good practise to use const keyword, when you know, it not going to change during compile time. In your case add it in Center() widget .

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