Sizer

Sizer (Responsive UI solution for Mobile App,Web and Desktop)

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A Flutter package that simplifies responsive design by automatically adapting your app’s UI to any screen size — making responsiveness seamless and intuitive.

Content

• Installation
• How to use
• Guideline
• Note
• FAQ

Installation ⬇️

Add sizer to pubspec.yaml

dependencies:
  sizer: ^3.1.3

How to use ⚙️

Import the Package

import 'package:sizer/sizer.dart';

Wrap MaterialApp with Sizer widget

Sizer( 
  builder: (context, orientation, screenType) {
    return MaterialApp(
      home: HomePage(),
    );
  },
);

Widget Size

Container(
  width: Adaptive.w(20),    // This will take 20% of the screen's width
  height: 30.5.h     // This will take 30.5% of the screen's height
)

Font size

Text(
  'Sizer', 
  style: TextStyle(fontSize: 15.dp), 
  // 15.sp can also be used instead of .dp
  // To know their differences, check #FAQ
)

Orientation

If your app needs to work seamlessly in both portrait and landscape orientations

Device.orientation == Orientation.portrait
  ? Container(   // Widget for Portrait
      width: 100.w,
      height: 20.5.h,
   )
  : Container(   // Widget for Landscape
      width: 100.w,
      height: 12.5.h,
   )

ScreenType

Same layout to look different in tablet and mobile, use the Device.screenType method:

Device.screenType == ScreenType.tablet
  ? Container(   // Widget for Tablet
      width: 100.w,
      height: 20.5.h,
   )
  : Container(   // Widget for Mobile
      width: 100.w,
      height: 12.5.h,
   )

*Device.ScreenType can not be Desktop unless maxTabletWidth is set

Guideline

Sizer

• maxMobileWidth - Maximum width of a mobile device (If the device's width is larger than this, it will be categorized as a tablet) - Default value: 599
• maxTabletWidth - Maximum width of a tablet device (If the device's width is larger than this, it will be categorized as a desktop) - Optional: enables Desktop ScreenType if enabled

Extensions

• Adaptive.h() or .h - Calculated percentage of the device's height (40.h -> 40% of device's height)
• Adaptive.w() or .w - Calculated percentage of the device's width (40.w -> 40% of device's width)
• Adaptive.sp() or .sp - Calculated sp based on the device's pixel density and aspect ratio (See FAQ)
• Adaptive.dp() or .dp - Calculated dp based on the device's pixel density (See FAQ)

*Note: Only use .sh and .sw if you want height and width to depend on the device's available height and width after applying SafeArea. Use .h and .w by default.

• Adaptive.sh() or .sh - Calculated percentage of the remaining device's height after applying SafeArea
• Adaptive.sw() or .sw - Calculated percentage of the remaining device's width after applying SafeArea

• Device.boxConstraints - BoxConstraints of the device
• Device.orientation - Screen Orientation of the device (portrait or landscape)
• Device.screenType - Screen type of the device (mobile or tablet)
• Device.aspectRatio - Aspect ratio of the device
• Device.pixelRatio - Pixel density ratio of the device

• Adaptive.cm() or .cm - The respective value in value in centimeters
• Adaptive.mm() or .mm - The respective value in value in millimeters
• Adaptive.Q() or .Q - The respective value in quarter-millimeters
• Adaptive.inches() or .inches - The respective value in inches
• Adaptive.pc() or .pc - The respective value in picas (1/6th of 1 inch)
• Adaptive.pt() or .pt - The respective value in points (1/72th of 1 inch)
• Adaptive.px() or .px - The respective value in pixels

Note

You need to import sizer package in order to access number.h, number.w, number.dp, and number.sp

Auto import in VSCode and Android Studio doesn't work for dart extension methods. Typing 10.h would not bring up auto import suggestion for this package

One workaround is to type Device so that the auto import suggestion would show up:

import 'package:sizer/sizer.dart';

FAQ

What is the difference between .sp and .dp?

.dp is supposedly calculated see below based on Material Design's dp calculation while.sp is calculated based on the device's pixel density and aspect ratio

Why is dp not calculated using the device's screen density?

Since there is no way to obtain a device's physical width in inches, we could not calculate for screen density. Material Design's screen density calculation involves a device's physical width in inches. As an alternative, dp is calculated using the device's pixel ratio.

Community Support

If you have any suggestions or issues, feel free to open an issue

If you would like to contribute, feel free to create a PR