pulltorefresh_flutter 0.1.4

A control that make the ScrollView to be pull to refresh and push to load data.Theoretically compatible with all Scrollable Widgets

example/example.dart

import 'dart:convert';
import 'dart:io';

import 'package:flutter/material.dart';
import 'package:flutter/rendering.dart';
import 'package:pulltorefresh_flutter/pulltorefresh_flutter.dart';


class PullAndPushTest extends StatefulWidget{

  @override
  State<StatefulWidget> createState() {
    return new PullAndPushTestState();
  }
}

///PullAndPush可以使用默认的样式，在此样式的基础上可以使用default**系列的属性改变显示效果，也可以自定义RefreshBox的样式（footerRefreshBox or headerRefreshBox）,也就是说可以定义其中一个，另一个用默认的，也可以全部自定义
///isPullEnable;isPushEnable属性可以控制RefreshBox 是否可用，无论是自定义的还是默认的
///PullAndPush can use the default style，Based on this style, you can use the properties of the default** series to change the display，
///You can also customize the style of the RefreshBox (footerRefreshBox or headerRefreshBox), which means you can define one of them, and the other can be customized by default or all.
class PullAndPushTestState extends State<PullAndPushTest> with TickerProviderStateMixin{
  List<String> addStrs=["a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"];
  List<String> strs=["1","2","3","4","5","6","7","8","9","0"];
  ScrollController controller=new ScrollController();
  //For compatibility with ios ,must use RefreshAlwaysScrollPhysics ;为了兼容ios 必须使用RefreshAlwaysScrollPhysics
  ScrollPhysics scrollPhysics=new RefreshAlwaysScrollPhysics();
  //使用系统的请求
  var httpClient = new HttpClient();
  var url = "https://github.com/";
  var _result="";
  String customRefreshBoxIconPath="images/icon_arrow.png";
  AnimationController customBoxWaitAnimation;
  double rotationAngle=0.0;


  @override
  void initState() {
    super.initState();
    //这个是刷新时控件旋转的动画，用来使刷新的Icon动起来
    customBoxWaitAnimation=new AnimationController(duration: const Duration(milliseconds: 1000*100), vsync: this);
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
        appBar: new AppBar(
          title: new Text("上下拉刷新"),
        ),
        body: new PullAndPush(
          //如果你headerRefreshBox和footerRefreshBox全都自定义了，则default**系列的属性均无效，假如有一个RefreshBox是用默认的（在该RefreshBox Enable的情况下）则default**系列的属性均有效
          //If your headerRefreshBox and footerRefreshBox are all customizable，then the default** attributes of the series are invalid，
          // If there is a RefreshBox is the default（In the case of the RefreshBox Enable）then the default** attributes of the series are valid
          defaultRefreshBoxTipText: "正在加载，请等待！",
          headerRefreshBox: new Container(
              color: Colors.black54,
              child:  new Row(
                mainAxisAlignment: MainAxisAlignment.center,
                children: <Widget>[
                  new Align(
                    alignment: Alignment.centerLeft,
                    child: new ClipRect(
                      child: new Transform(
                        origin: new Offset(45.0/2, 45.0/2),
                        transform: Matrix4.rotationX(rotationAngle),
                        child: new RotationTransition( //布局中加载时动画的weight
                          child: new Image.asset(
                            customRefreshBoxIconPath,
                            height: 45.0,
                            width: 45.0,
                          ),
                          turns: new Tween(
                              begin: 100.0,
                              end: 0.0
                          )
                              .animate(customBoxWaitAnimation)
                            ..addStatusListener((animationStatus) {
                              if (animationStatus == AnimationStatus.completed) {
                                customBoxWaitAnimation.repeat();
                              }
                            }
                            ),
                        ),
                      ),
                    ),
                  ),

                  new Align(
                    alignment: Alignment.centerRight,
                    child:new ClipRect(
                      child:new Text("快尼玛给老子松手！",style: new TextStyle(fontSize: 18.0,color: Color(0xffe6e6e6)),),
                    ),
                  ),
                ],
              )
          ),

          //你也可以自定义底部的刷新栏；you can customize the bottom refresh box

          animationStateChangedCallback:(AnimationStates animationStates,RefreshBoxDirectionStatus refreshBoxDirectionStatus){
            switch (animationStates){
            //RefreshBox高度没有达到50，上下拉刷新不可用（此状态下RefreshBox会自动弹回去）；RefreshBox height not reached 50，the function of load data is not available（In this state RefreshBox Will automatically bounce back）
              case AnimationStates.DragAndRefreshNotEnabled:
                break;

            //RefreshBox高度达到50,上下拉刷新可用;RefreshBox height reached 50，the function of load data is  available
              case AnimationStates.DragAndRefreshEnabled:
                setState(() {
                  //3.141592653589793是弧度，角度为180度；3.141592653589793 is radians，angle is 180⁰
                  rotationAngle=3.141592653589793;
                });
                break;

            //抬起手指后。RefreshBox 弹回到50的高度，的过程；After lifting your finger，the process of RefreshBox bounce back to the height of 50，
              case AnimationStates.ReboundToBoxHeight:
                setState(() {
                  customRefreshBoxIconPath="images/refresh.png";
                });
                break;

            //开始加载数据时；When loading data starts
              case AnimationStates.StartLoadData:
                customBoxWaitAnimation.forward();
                break;

            //加载完数据并RefreshBox开始消失时；After loading the data and the RefreshBox begins to disappear
              case AnimationStates.LoadDataEndAndBoxDisappear:
                customBoxWaitAnimation.reset();
                break;

            //RefreshBox已经消失，并且闲置；RefreshBox has disappeared and is idle
              case AnimationStates.RefreshBoxIdle:
                print("------");
                setState(() {
                  rotationAngle=0.0;
                  customRefreshBoxIconPath="images/icon_arrow.png";
                });
                break;
            }
          },
          listView: new ListView.builder(
            //ListView的Item
              itemCount: strs.length,//+2,
              controller: controller,
              physics: scrollPhysics,
              itemBuilder: (BuildContext context,int index){
                return new Container(
                  color: Colors.black54,
                  height: 35.0,
                  child: new Center(
                    child: new Text(strs[index],style: new TextStyle(fontSize: 18.0),),
                  ),
                );
              }
          ),
          loadData: (isPullDown) async{
            try {
              var request = await httpClient.getUrl(Uri.parse(url));
              var response = await request.close();
              if (response.statusCode == HttpStatus.ok) {
                _result = await response.transform(utf8.decoder).join();
                setState(() {
                  //拿到数据后，对数据进行梳理
                  if(isPullDown){
                    strs.clear();
                    strs.addAll(addStrs);
                  }else{
                    strs.addAll(addStrs);
                  }
                });
              } else {
                _result = 'error code : ${response.statusCode}';
              }
            } catch (exception) {
              _result = '网络异常';
            }
            print(_result);
          },
          scrollPhysicsChanged: (ScrollPhysics physics) {
            setState(() {
              scrollPhysics=physics;
            });
          },
        )
    );
  }
}