App_Flutter/lib/extension/layout.dart

import 'package:flutter/material.dart';
extension LayoutX<T extends Widget> on T {
  //
  // SizedBox wrapContent() {
  //   return SizedBox.shrink(child: this);
  // }
  //
  // SizedBox matchParent() {
  //   return SizedBox.expand(child: this);
  // }

  //  布局

  Padding paddingAll(double size) {
    return padding(left: size, right: size, top: size, bottom: size);
  }

  Padding get paddingZero => padding();

  Padding paddingSymmetric({double horizontal = 0, double vertical = 0}) {
    return padding(left: horizontal, right: horizontal, top: vertical, bottom: vertical);
  }

  Padding paddingLeft(double size) {
    return padding(left: size);
  }

  Padding paddingRight(double size) {
    return padding(right: size);
  }

  Padding paddingTop(double size) {
    return padding(top: size);
  }

  Padding paddingBottom(double size) {
    return padding(bottom: size);
  }

  Padding padding({double left = 0, double top = 0, double right = 0, double bottom = 0}) {
    return Padding(
      padding: EdgeInsets.only(left: left, top: top, right: right, bottom: bottom),
      child: this,
    );
  }

  //______margin_______

  Container marginAll(double size) {
    return margin(left: size, right: size, top: size, bottom: size);
  }

  Container get marginZero => margin();

  Container marginSymmetric({double horizontal = 0, double vertical = 0}) {
    return margin(left: horizontal, right: horizontal, top: vertical, bottom: vertical);
  }

  Container marginLeft(double size) {
    return margin(left: size);
  }

  Container marginRight(double size) {
    return margin(right: size);
  }

  Container marginTop(double size) {
    return margin(top: size);
  }

  Container marginBottom(double size) {
    return margin(bottom: size);
  }

  Container margin({double left = 0, double top = 0, double right = 0, double bottom = 0}) {
    return Container(
      margin: EdgeInsets.only(left: left, top: top, right: right, bottom: bottom),
      child: this,
    );
  }

  //transform 变换

  Transform translate(double dx, double dy) {
    return Transform.translate(
      offset: Offset(dx, dy),
      child: this,
    );
  }

  Transform rotate(double angle) {
    return Transform.rotate(
      angle: angle,
      child: this,
    );
  }

  Transform scale(double scale) {
    return Transform.scale(
      scale: scale,
      child: this,
    );
  }

  //Flex
  Flexible flexible({
    int flex = 1,
    FlexFit fit = FlexFit.loose,
  }) {
    return Flexible(flex: flex, fit: fit, child: this);
  }

  Expanded expanded() {
    return Expanded(child: this);
  }

  Positioned positioned(
      {double? left, double? right, double? top, double? bottom, double? width, double? height}) {
    return Positioned(
      child: this,
      left: left,
      right: right,
      top: top,
      bottom: bottom,
      width: width,
      height: height,
    );
  }

  //套入一个方形的盒子
  // SizedBox square(double size) {
  //   return SizedBox.square(child: this, dimension: size);
  // }

  //尺寸相关

  SizedBox height(double? height) {
    return SizedBox(height: height, child: this);
  }

  SizedBox width(double? width) {
    return SizedBox(width: width, child: this);
  }

  ConstrainedBox maxWidth(double? size) {
    return constraints(maxWidth: size);
  }

  ConstrainedBox maxHeight(double? size) {
    return constraints(maxHeight: size);
  }

  ConstrainedBox minWidth(double? size) {
    return constraints(minWidth: size);
  }

  ConstrainedBox minHeight(double? size) {
    return constraints(minHeight: size);
  }

  SizedBox size({double? width, double? height}) {
    return SizedBox(width: width, height: height, child: this);
  }

  

  ///aspect ratio 纵横比
  AspectRatio aspectRatio(double aspectRatio) {
    return AspectRatio(
      child: this,
      aspectRatio: aspectRatio,
    );
  }


ConstrainedBox constraints(
      {double? maxWidth, double? maxHeight, double? minWidth, double? minHeight}) {
    BoxConstraints constraints = BoxConstraints(
        maxWidth: maxWidth ?? double.infinity,
        maxHeight: maxHeight ?? double.infinity,
        minWidth: minWidth ?? 0,
        minHeight: minHeight ?? 0);

    if (this is ConstrainedBox) {
      var thisConstraints = (this as ConstrainedBox).constraints;
      constraints =
          maxWidth?.let((it) => thisConstraints.copyWith(maxWidth: maxWidth)) ?? thisConstraints;
      constraints =
          maxHeight?.let((it) => thisConstraints.copyWith(maxWidth: maxWidth)) ?? thisConstraints;
      constraints =
          minWidth?.let((it) => thisConstraints.copyWith(maxWidth: maxWidth)) ?? thisConstraints;
      constraints =
          minHeight?.let((it) => thisConstraints.copyWith(maxWidth: maxWidth)) ?? thisConstraints;
    }
    return ConstrainedBox(constraints: constraints, child: this);
  }

}

extension ScopeEx<T> on T {
  T also(Function(T it) function) {
    function(this);
    return this;
  }

  R let<R>(R Function(T it) function) {
    return function(this);
  }
}