Proportionate Screen Height and Width

size_config.dart

import 'package:flutter/material.dart';

class SizeConfig {
  static SizeConfig _instance;
  static BuildContext context;
  static SizeConfig instance(BuildContext context) {
    if (_instance == null) _instance = SizeConfig._init(context);
    return _instance;
  }

  static MediaQueryData _mediaQueryData;
  static double _screenWidth;
  static double _screenHeight;

  SizeConfig._init(BuildContext context) {
    _mediaQueryData = MediaQuery.of(context);
    _screenWidth = _mediaQueryData.size.width;
    _screenHeight = _mediaQueryData.size.height;
  }

  double getProportionateScreenHeight(double inputHeight) {
    double screenHeight = _screenHeight;
    return (inputHeight / 812.0) * screenHeight;
  }

  double getProportionateScreenWidth(double inputWidth) {
    double screenWidth = _screenWidth;
    return (inputWidth / 375.0) * screenWidth;
  }

  double getScreenWidth() {
    return _screenWidth;
  }

  double getScreenHeight() {
    return _screenHeight;
  }
}