How to use Themes in Flutter

How to use Themes in Flutter: - Click here
Output Screenshot:
change themes inside Scaffold,AppBar for body and appbar resp
apply theme text and body

SOLUTION
To do that, we will create a new ThemeData object first.
Step 1:

final globalTheme = ThemeData(
  primarySwatch: Colors.deepOrange,
  textTheme: const TextTheme(
    bodyText1: TextStyle(
      fontSize: 22,
      height: 1.2,
    ),
    bodyText2: TextStyle(
      color: Colors.blue,
      fontSize: 20,
      fontWeight: FontWeight.bold,
      height: 1.0,
    ),
    caption: TextStyle(
      fontSize: 16,
      fontWeight: FontWeight.bold,
      fontStyle: FontStyle.italic,
      height: 1.2,
    ),
    headline1: TextStyle(
      color: Colors.deepOrange,
      fontFamily: 'Allison',
      fontWeight: FontWeight.bold,
      fontSize: 60,
    ),
    headline2: TextStyle(
      color: Colors.black38,
      fontSize: 30,
      fontWeight: FontWeight.bold,
    ),
  ),
  appBarTheme: const AppBarTheme(
    backgroundColor: Colors.amber,
    // This will control the "back" icon
    iconTheme: IconThemeData(color: Colors.red),
    // This will control action icon buttons that locates on the right
    actionsIconTheme: IconThemeData(color: Colors.blue),
    centerTitle: false,
    elevation: 15,
    titleTextStyle: TextStyle(
      color: Colors.deepPurple,
      fontFamily: 'Allison',
      fontWeight: FontWeight.bold,
      fontSize: 40,
    ),
  ),
);

Text(
            'Headline 1',
            style: globalTheme.textTheme.headline1,
          ),

Text(
            'Headline 2',
            style: globalTheme.textTheme.headline2,
          ),

 Container(
            margin: const EdgeInsets.all(5),
            padding: const EdgeInsets.all(5),
            child: Text(
              'Body Text 2: Here goes some more information regarding your works.',
              style: globalTheme.textTheme.bodyText2,
            ),
          ),

Full code


import 'package:flutter/src/foundation/key.dart';
import 'package:flutter/src/widgets/framework.dart';

import 'dart:io';

import 'package:flutter/material.dart';
import 'package:holidaylandmark/main.dart';
import 'package:intl/intl.dart';


class Experiment extends StatefulWidget {
   Experiment({Key? key}) : super(key: key);

  @override
  State<Experiment> createState() => _ExperimentState();
}
class _ExperimentState extends State<Experiment> {
  final globalTheme = ThemeData(
  primarySwatch: Colors.deepOrange,
  textTheme: const TextTheme(
    bodyText1: TextStyle(
      fontSize: 22,
      height: 1.2,
    ),
    bodyText2: TextStyle(
      color: Colors.blue,
      fontSize: 20,
      fontWeight: FontWeight.bold,
      height: 1.0,
    ),
    caption: TextStyle(
      fontSize: 16,
      fontWeight: FontWeight.bold,
      fontStyle: FontStyle.italic,
      height: 1.2,
    ),
    headline1: TextStyle(
      color: Colors.deepOrange,
      fontFamily: 'Allison',
      fontWeight: FontWeight.bold,
      fontSize: 60,
    ),
    headline2: TextStyle(
      color: Colors.black38,
      fontSize: 30,
      fontWeight: FontWeight.bold,
    ),
  ),
  appBarTheme: const AppBarTheme(
    backgroundColor: Colors.amber,
    // This will control the "back" icon
    iconTheme: IconThemeData(color: Colors.red),
    // This will control action icon buttons that locates on the right
    actionsIconTheme: IconThemeData(color: Colors.blue),
    centerTitle: false,
    elevation: 15,
    titleTextStyle: TextStyle(
      color: Colors.deepPurple,
      fontFamily: 'Allison',
      fontWeight: FontWeight.bold,
      fontSize: 40,
    ),
  ),
);
  @override
  Widget build(BuildContext context) {
  DateTime now = DateTime.now();
    String stringDate = DateFormat('yyyy-MM-dd – kk:mm').format(now);
    return Scaffold(
    //  backgroundColor:globalTheme.backgroundColor,       
        appBar: AppBar(
        //  backgroundColor:globalTheme.backgroundColor,
          title: Text(
            'holidaylandmark',
            style: TextStyle(
              fontSize: 23.0,
            ),
          ),
        ),
        body: Center(
      child: Column(
        children: [
          const SizedBox(
            height: 10,
          ),
          Container(
            height: 70,
            width: 70,
            color: Colors.blue[50],
            child: const Align(
              alignment: Alignment.topCenter,
              child: FlutterLogo(
                size: 60,
              ),
            ),
          ),
          const SizedBox(
            height: 10,
          ),
          Text(
            'Headline 1',
            style: globalTheme.textTheme.headline1,
          ),
          const SizedBox(
            height: 10,
          ),
          Text(
            'Headline 2',
            style: globalTheme.textTheme.headline2,
          ),
          Container(
            margin: const EdgeInsets.all(5),
            padding: const EdgeInsets.all(5),
            child: Text(
              'Body Text 1: Here goes some introduction about yourself.',
              style: globalTheme.textTheme.bodyText1,
            ),
          ),
          Container(
            margin: const EdgeInsets.all(5),
            padding: const EdgeInsets.all(5),
            child: Text(
              'Body Text 2: Here goes some more information regarding your works.',
              style: globalTheme.textTheme.bodyText2,
            ),
          ),
          Container(
            margin: const EdgeInsets.all(5),
            padding: const EdgeInsets.all(5),
            child: Text(
              stringDate,
              style: globalTheme.textTheme.caption,
            ),
          ),
        ],
      ),
    ));
  }
}

class T {}

Output:

Change backgroundColor of body

Change backgroundColor of appbar

Output:

** output**

** SOLUTION**

import 'package:flutter/src/foundation/key.dart';
import 'package:flutter/src/widgets/framework.dart';

import 'dart:io';

import 'package:flutter/material.dart';
import 'package:holidaylandmark/main.dart';

class Experiment extends StatefulWidget {
  Experiment({Key? key}) : super(key: key);

  @override
  State<Experiment> createState() => _ExperimentState();
}

class _ExperimentState extends State<Experiment> {

  @override
  Widget build(BuildContext context) {
    return Theme(
      data: Theme.of(context).copyWith(
        cardColor: Colors.white,
        textTheme: Theme.of(context).textTheme.apply(bodyColor: Colors.black),
      ),
      child: Builder(
        builder: (context) {
          return RaisedButton(
            child: Text("Show menu"),
            onPressed: () {
              showMenu(
                context: context,
                position: RelativeRect.fromLTRB(0, 100, 0, 0),
                items: [
                  PopupMenuItem(child: Text("Item 0"), value: 0),
                  PopupMenuItem(child: Text("Item 1"), value: 1),
                  PopupMenuItem(child: Text("Item 2"), value: 2),
                ],
              );
            },
          );
        },
      ),
    );
  }
}

*SOLUTION *

OUTPUT

*SOLUTION *

Full Summary:
`

Inside Container-Colors.colorName.withOpacity(opacity).
Inside Appbar-backgroundColor: Color.fromRGBO.
Inside opacity-opacity,Container.
Inside Widget build--Appbar,body-Container
Appbar--Title,backgroundColor
body-Container---Color,Stack-children-Image,Container(width,color,margin,padding,child: Text)`

Refrence
Click here
Click here
Click here

Debug School

How to use Themes in Flutter

Top comments (0)