huixiang_app/lib/home/activity_list_page.dart

import 'package:flutter/material.dart';
import 'package:huixiang/view_widget/item_title.dart';
import 'package:huixiang/view_widget/round_button.dart';

class ActivityListPage extends StatefulWidget {
  @override
  State<StatefulWidget> createState() {
    return _ActivityListPage();
  }
}

class _ActivityListPage extends State<ActivityListPage> {
  @override
  Widget build(BuildContext context) {
    return Container(
      child: AnimatedList(
        // key: _listKey,
        physics: BouncingScrollPhysics(),
        initialItemCount: size,
        itemBuilder: (context, position, animation) {
          return buildItem(position, animation);
        },
      ),
    );
  }

  // final GlobalKey<AnimatedListState> _listKey = GlobalKey<AnimatedListState>();
  int size = 15;
  //
  // void _addItem() {
  //   _listKey.currentState.insertItem(size);
  //   size += 1;
  // }
  //
  // void _removeItem() {
  //   final int _index = size - 1;
  //   _listKey.currentState.removeItem(
  //       _index, (context, animation) => buildItem(_index, animation));
  //   size -= 1;
  // }

  Widget buildItem(position, animation) {
    if (position % 3 == 0) {
      return SizeTransition(
        sizeFactor: animation/*.drive(CurveTween(curve: Curves.easeIn)).drive(
          Tween<Offset>(begin: Offset(1, 1), end: Offset(0, 1)),
        )*/,
        child: activityTitleItem(),
      );
    } else {
      return SizeTransition(
          sizeFactor: animation/*.drive(
            CurveTween(curve: Curves.easeIn),).drive(
            Tween<Offset>(
              begin: Offset(1, 1),
              end: Offset(0, 1),
            ),
          )*/,
          child: activityItem());
    }
  }

  Widget activityTitleItem() {
    return Container(
      child: Column(
        children: [
          ItemTitle(text: "进行中活动", imgPath: "assets/image/icon_today_task.png"),
          activityItem()
        ],
      ),
    );
  }

  Widget activityItem() {
    return Container(
      margin: EdgeInsets.all(16),
      decoration: BoxDecoration(
          color: Colors.white,
          boxShadow: [
            BoxShadow(
                color: Colors.black.withAlpha(12),
                offset: Offset(0, 3),
                blurRadius: 14,
                spreadRadius: 0)
          ],
          borderRadius: BorderRadius.all(Radius.circular(8))),
      child: Column(
        children: [
          ClipRRect(
            borderRadius: BorderRadius.only(
                topLeft: Radius.circular(8), topRight: Radius.circular(8)),
            child: Image.network(
              "https://t7.baidu.com/it/u=1297102096,3476971300&fm=193&f=GIF",
              fit: BoxFit.cover,
            ),
          ),
          Container(
            padding: EdgeInsets.only(left: 16, right: 16, top: 8, bottom: 12),
            child: Column(
              mainAxisAlignment: MainAxisAlignment.spaceAround,
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Text(
                  "评选人们最喜欢的美食！",
                  style: TextStyle(
                      fontWeight: FontWeight.bold,
                      fontSize: 14,
                      color: Colors.black),
                ),
                Text(
                  "评选人们最喜欢的美食！",
                  style: TextStyle(fontSize: 10, color: Color(0xFF727272)),
                ),
                Row(
                  crossAxisAlignment: CrossAxisAlignment.end,
                  mainAxisAlignment: MainAxisAlignment.spaceBetween,
                  children: [
                    Text(
                      "海峡姐妹",
                      style: TextStyle(color: Color(0xFF060606), fontSize: 12),
                    ),
                    Column(
                      crossAxisAlignment: CrossAxisAlignment.end,
                      mainAxisAlignment: MainAxisAlignment.center,
                      children: [
                        Text(
                          "13:11",
                          style: TextStyle(
                              color: Color(0xFF32A060),
                              fontSize: 12,
                              fontWeight: FontWeight.bold),
                        ),
                        Text(
                          "2020.01.08",
                          style: TextStyle(
                              color: Color(0xFF32A060),
                              fontSize: 12,
                              fontWeight: FontWeight.bold),
                        ),
                      ],
                    )
                  ],
                )
              ],
            ),
          )
        ],
      ),
    );
  }
}