flutter_screenutil

A flutter plugin for adapting screen and font size.Let your UI display a reasonable layout on different screen sizes!

Note: This plugin is still under development, and some APIs might not be available yet.

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Update log

Usage:

Add dependency：

Please check the latest version before installation. If there is any problem with the new version, please use the previous version

dependencies:
  flutter:
    sdk: flutter
  # add flutter_screenutil
  flutter_screenutil: ^4.0.0-beta1

Add the following imports to your Dart code:

import 'package:flutter_screenutil/flutter_screenutil.dart';

Property

Property	Type	Default Value	Description
designSize	Size	Size(1080, 1920)	The size of the device in the design draft, in px
allowFontScaling	bool	false	Sets whether the font size is scaled according to the system's "font size" assist option

Initialize and set the fit size and font size to scale according to the system's "font size" accessibility option

Please set the size of the design draft before use, the width and height of the design draft.

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return LayoutBuilder(
      builder: (context, constraints) {
        //Set the fit size (fill in the screen size of the device in the design) If the design is based on the size of the iPhone6 ​​(iPhone6 ​​750*1334)
        ScreenUtil.init(constraints, designSize: Size(750, 1334), allowFontScaling: false);

        return MaterialApp(
          ...
        );
      },
    );
  }
}

//fill in the screen size of the device in the design

//default value : width : 1080px , height:1920px , allowFontScaling:false
ScreenUtil.init(constraints);

//If the design is based on the size of the iPhone6 ​​(iPhone6 ​​750*1334)
ScreenUtil.init(constraints, designSize: Size(750, 1334));

//If you want to set the font size is scaled according to the system's "font size" assist option
ScreenUtil.init(constraints, designSize: Size(750, 1334), allowFontScaling: true);

Use：

API

Pass the px size of the design draft

    ScreenUtil().setWidth(540)  (dart sdk>=2.6 : 540.w) //Adapted to screen width
    ScreenUtil().setHeight(200) (dart sdk>=2.6 : 200.h) //Adapted to screen height , under normal circumstances, the height still uses x.w
    ScreenUtil().setSp(24)      (dart sdk>=2.6 : 24.sp) //Adapter font
    ScreenUtil().setSp(24, allowFontScalingSelf: true)  (dart sdk>=2.6 : 24.ssp) //Adapter font(fonts will scale to respect Text Size accessibility settings)
    ScreenUtil().setSp(24, allowFontScalingSelf: false) (dart sdk>=2.6 : 24.nsp) //Adapter font(fonts will not scale to respect Text Size accessibility settings)

    ScreenUtil().pixelRatio       //Device pixel density
    ScreenUtil().screenWidth   (dart sdk>=2.6 : 1.sw)    //Device width
    ScreenUtil().screenHeight  (dart sdk>=2.6 : 1.sh)    //Device height
    ScreenUtil().bottomBarHeight  //Bottom safe zone distance, suitable for buttons with full screen
    ScreenUtil().statusBarHeight  //Status bar height , Notch will be higher Unit px
    ScreenUtil().textScaleFactor  //System font scaling factor

    ScreenUtil().scaleWidth //Ratio of actual width dp to ui design
    ScreenUtil().scaleHeight //Ratio of actual height dp to ui design

    0.2.sw  //0.2 times the screen width
    0.5.sh  //50% of screen height

Adapt screen size：

Pass the px size of the design draft((The unit is the same as the unit at initialization))：

Adapted to screen width: ScreenUtil().setWidth(540),

Adapted to screen height: ScreenUtil().setHeight(200), In general, the height is best to adapt to the width

If your dart sdk>=2.6, you can use extension functions:

example:

instead of :

Container(
width: ScreenUtil().setWidth(50),
height:ScreenUtil().setHeight(200),
)

you can use it like this:

Container(
width: 50.w,
height:200.h
)

Note

The height can also use setWidth to ensure that it is not deformed(when you want a square)

setHeight method is mainly adapted in height, you want to control the height and actuality of a screen on the UIUsed when the same is displayed.

//for example:

///If you want to display a square:
///rectangle
Container(
           width: ScreenUtil().setWidth(375),
           height: ScreenUtil().setWidth(200),
            ),
            
////If you want to display a square:
Container(
           width: ScreenUtil().setWidth(300),
           height: 300.w,
            ),

Adapter font:

//Incoming font size(The unit is the same as the unit at initialization), fonts will not scale to respect Text Size accessibility settings
//(AllowallowFontScaling when initializing ScreenUtil)
ScreenUtil().setSp(28) 
28.sp   
     
//Incoming font size，the unit is pixel，fonts will scale to respect Text Size accessibility settings
//(If somewhere follow the global allowFontScaling setting)
ScreenUtil().setSp(24, allowFontScalingSelf: true)
28.ssp

//(If somewhere does not follow the global allowFontScaling setting)
ScreenUtil().setSp(24, allowFontScalingSelf: false)
28.nsp

//for example:
Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: <Widget>[
                Text(
                    'My font size is 24px on the design draft and will not change with the system.',
                    style: TextStyle(
                      color: Colors.black,
                      fontSize: ScreenUtil().setSp(24),
                    )),
                Text(
                    'My font size is 24px on the design draft and will change with the system.',
                    style: TextStyle(
                        color: Colors.black,
                        fontSize: ScreenUtil()
                            .setSp(24, allowFontScalingSelf: true))),
              ],
            )

widget test

Example:

example demo

Effect: