Flutter MergeableMaterialItem-白红宇

简介

MaterialSlice 和 MaterialGap的基本类型

所有的MergeableMaterialItem对象都需要LocalKey

基础用法

MaterialSlice进行演示

MaterialSlice做为 MergeableMaterial子类。它作为Material,可以和其他的slices合并使用

实例演示

import 'package:flutter/material.dart';class MergeableMaterialItemDemo extends StatefulWidget {  _MergeableMaterialItemState createState() => _MergeableMaterialItemState();}class _MergeableMaterialItemState extends State
     
       {  final List
      
        items = 
       
        [];  bool currIndex = false;  int currIndexNum = 1;  _isChildExpanded() {    setState(() {      currIndex ? currIndex = false : currIndex = true;      currIndexNum++;    });  }  @override  Widget build(BuildContext context) {    items.add(        //class MaterialSlice extends MergeableMaterialItem         MaterialSlice(            key:  ValueKey
        
         (currIndexNum),            child:  Column(children: 
         
          [              // header,               AnimatedCrossFade(                firstChild:  Container(                  height: 20.0,                  width: 20.0,                  color: Colors.green,                ),                secondChild:  Container(                  height: 20.0,                  width: 20.0,                  color: Colors.red,                ),                crossFadeState: currIndex                    ? CrossFadeState.showSecond                    : CrossFadeState.showFirst,                firstCurve:                    const Interval(0.0, 0.6, curve: Curves.fastOutSlowIn),                secondCurve:                    const Interval(0.4, 1.0, curve: Curves.fastOutSlowIn),                sizeCurve: Curves.fastOutSlowIn,                duration: Duration(microseconds: 6),              )            ])));    return Column(      children: 
          
           [ MergeableMaterial(hasDividers: true, children: items), RaisedButton( child: Text("点击添加"), onPressed: () { _isChildExpanded(); }, ) ], ); }}