sizer 1.1.5 
sizer: ^1.1.5 copied to clipboard
A flutter plugin for Easily make Flutter apps responsive. Automatically adapt UI to different screen sizes. Responsiveness made simple.
sizer #
A flutter plugin for Easily make Flutter apps responsive. Automatically adapt UI to different screen sizes. Responsiveness made simple.
Installation ⬇️ #
Add to pubspec.yaml.
dependencies:
  ...
  sizer: ^1.1.5
How to use 💻 #
Add the following imports to your Dart code:
import 'package:sizer/sizer.dart';
- First need to Initialize SizerUtil.init() method inside main.dart.
 - In main.dart must have to use LayoutBuilder and OrientationBuilder.
 - See below explain for more details.
 
import 'package:flutter/material.dart';
import 'login_screen.dart'; 
import 'package:sizer/sizer.dart';
void main() {
  runApp(MyApp());
}
class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return LayoutBuilder(                           //return LayoutBuilder
      builder: (context, constraints) {
        return OrientationBuilder(                  //return OrientationBuilder
          builder: (context, orientation) {
            //initialize SizerUtil()
            SizerUtil().init(constraints, orientation);  //initialize SizerUtil
            return MaterialApp(
              debugShowCheckedModeBanner: false,
              title: 'Sizer',
              theme: ThemeData.light(),
              home: LoginScreen(),
            );
          },
        );
      },
    );
  }
}
You can use it like this:
Whenever you use height and width first import sizer package.
import 'package:sizer/sizer.dart';
Widget Size 🕓
    Container(
      width: 20.0.w,    //It will take a 20% of screen width
      height:30.0.h     //It will take a 20% of screen height
    )
Padding ⏹
    Padding(
      padding: EdgeInsets.symmetric(vertical: 5.0.h, horizontal: 3.0.h),
      child: Container(),
    );
Font size 🆎
    Text(
      'Sizer',style: TextStyle(fontSize: 15.0.sp),
    );
Square Widget 🟩
If you want to make square size widget then give height or width in both height and width.
    Container(
            width: 30.0.h,      //It will take a 20% of screen height
            height: 30.0.h,     //It will take a 20% of screen height
    );
Orientation 🔄
If you want to give support for landscape
appBar() {
    return SizerUtil.orientation == Orientation.portrait
        ? Container(
            width: 100.0.w,
            height: 20.0.h,
          )                     //for portrait screen
        : Container(
            width: 100.0.w,
            height: 12.0.h,
          );                    //for landscape screen
  }
DeviceType 📱
If you want the same layout to look different in tablet and mobile then use SizerUtil.getDeviceType method
SizerUtil.getDeviceType
You can use it like this:
 appBar() {
    return SizerUtil.getDeviceType == DeviceScreenType.Tablet
        ? Container(
            width: 100.0.w,
            height: 20.0.h,
          )                     //for Tablet
        : Container(
            width: 100.0.w,
            height: 12.0.h,
          );                    //for Mobile
  }