How does flutter make screen adaptation?

how does flutter make screen adaptation

Ios android
Mar.25,2022

refer to https://github.com/OpenFlutte.

. 
/*
 * Created by  on 2018/9/29.
 * email: zhuoyuan93@gmail.com
 */

import 'package:flutter/material.dart';

class ScreenUtil {
  static ScreenUtil instance = new ScreenUtil();

  /// UI , px
  /// Size of the phone in UI Design , px
  double width;
  double height;

  /// "" false
  /// allowFontScaling Specifies whether fonts should scale to respect Text Size accessibility settings. The default is false.
  bool allowFontScaling;

  static MediaQueryData _mediaQueryData;
  static double _screenWidth;
  static double _screenHeight;
  static double _pixelRatio;
  static double _statusBarHeight;

  static double _bottomBarHeight;

  static double _textScaleFactor;

  ScreenUtil({
    this.width = 1080,
    this.height = 1920,
    this.allowFontScaling = false,
  });

  static ScreenUtil getInstance() {
    return instance;
  }

  void init(BuildContext context) {
    MediaQueryData mediaQuery = MediaQuery.of(context);
    _mediaQueryData = mediaQuery;
    _pixelRatio = mediaQuery.devicePixelRatio;
    _screenWidth = mediaQuery.size.width;
    _screenHeight = mediaQuery.size.height;
    _statusBarHeight = mediaQuery.padding.top;
    _bottomBarHeight = _mediaQueryData.padding.bottom;
    _textScaleFactor = mediaQuery.textScaleFactor;
  }

  static MediaQueryData get mediaQueryData => _mediaQueryData;

  /// 
  /// The number of font pixels for each logical pixel.
  static double get textScaleFactory => _textScaleFactor;

  /// 
  /// The size of the media in logical pixels (e.g, the size of the screen).
  static double get pixelRatio => _pixelRatio;

  ///  dp
  /// The horizontal extent of this size.
  static double get screenWidthDp => _screenWidth;

  /// dp
  ///The vertical extent of this size. dp
  static double get screenHeightDp => _screenHeight;

  ///  px
  /// The vertical extent of this size. px
  static double get screenWidth => _screenWidth * _pixelRatio;

  ///  px
  /// The vertical extent of this size. px
  static double get screenHeight => _screenHeight * _pixelRatio;

  ///  dp 
  /// The offset from the top
  static double get statusBarHeight => _statusBarHeight;

  ///  dp
  /// The offset from the bottom.
  static double get bottomBarHeight => _bottomBarHeight;

  /// dpUIpx
  /// The ratio of the actual dp to the design draft px
  get scaleWidth => _screenWidth / instance.width;

  get scaleHeight => _screenHeight / instance.height;

  /// UI
  /// ,.
  /// Adapted to the device width of the UI Design.
  /// Height can also be adapted according to this to ensure no deformation ,
  /// if you want a square
  setWidth(num width) => width * scaleWidth;

  /// UI
  /// UI,
  /// ,.
  /// UI
  /// Highly adaptable to the device according to UI Design
  /// It is recommended to use this method to achieve a high degree of adaptation
  /// when it is found that one screen in the UI design
  /// does not match the current style effect, or if there is a difference in shape.
  setHeight(num height) => height * scaleHeight;

  ///
  ///@param [fontSize] UI,px.
  ///Font size adaptation method
  ///@param [fontSize] The size of the font on the UI design, in px.
  ///@param [allowFontScaling]
  setSp(num fontSize) => allowFontScaling
      ? setWidth(fontSize)
      : setWidth(fontSize) / _textScaleFactor;
}

Previous: Vue-awesome-swiper 3.1.3 error Maximum call stack size exceeded

Next: What is the difference between getFieldDecorator and getFieldProps in rc-form?

css mysql arrays josn react html typescript webpack npm sass R objective-c .net sql-server jquery python-3.x angularjs django angular excel regex iphone ajax linux xml pandas vba spring database wordpress string wpf xcode windows bash postgresql oracle multithreading eclipse list firebase algorithm macos forms image scala visual-studio azure bootstrap spring-boot react-native python-2.7 docker performance function winforms matlab powershell apache dataframe api sqlite numpy rest shell selenium flutter dart maven loops qt swing android-studio csv express file class tensorflow sorting codeigniter perl
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1e5f6b3-45066.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1e5f6b3-45066.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Need Help?