flutter 使用 inview_notifier_list与pull_to_refresh_plus冲突无法刷新问题

siman · 20 小时前

SmartRefresher原因是 inview_notifier_list 在使用 InViewNotifierList 或 InViewNotifierCustomScrollView 是外层都包裹了一层InViewNotifier 造成pull_to_refresh_plus 这类插件无法刷新
我的解决方法是复写InViewNotifier
1.新建 aa.dart 把下面的代码复制进去

import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter/rendering.dart';
import 'package:stream_transform/stream_transform.dart';
import 'package:inview_notifier_list/src/inherited_inview_widget.dart';
import 'package:inview_notifier_list/src/inview_state.dart';
///builds a [ScrollView] and notifies when the widgets are on screen within a provided area.
class InViewNotifier extends StatefulWidget {
///The String list of ids of the child widgets that should be initialized as inView
///when the list view is built for the first time.
final List<String> initialInViewIds;
///The widget that should be displayed in the [InViewNotifier].
final Widget child;
///The distance from the bottom of the list where the [onListEndReached] should be invoked.
final double endNotificationOffset;
///The function that is invoked when the list scroll reaches the end
///or the [endNotificationOffset] if provided.
final VoidCallback? onListEndReached;
///The duration to be used for throttling the scroll notification.
///Defaults to 200 milliseconds.
final Duration throttleDuration;
///The axis along which the scroll view scrolls.
final Axis scrollDirection;
///The function that defines the area within which the widgets should be notified
///as inView.
final IsInViewPortCondition isInViewPortCondition;
InViewNotifier({
Key? key,
required this.child,
this.initialInViewIds = const [],
this.endNotificationOffset = 0.0,
this.onListEndReached,
this.throttleDuration = const Duration(milliseconds: 200),
this.scrollDirection = Axis.vertical,
required this.isInViewPortCondition,
}) : assert(endNotificationOffset >= 0.0),
super(key: key);
@override
_InViewNotifierState createState() => _InViewNotifierState();
static InViewState? of(BuildContext context) {
final widget = context
.getElementForInheritedWidgetOfExactType<InheritedInViewWidget>()!
.widget as InheritedInViewWidget;
return widget.inViewState;
}
}
class _InViewNotifierState extends State<InViewNotifier> {
InViewState? _inViewState;
StreamController<ScrollNotification>? _streamController;
@override
void initState() {
super.initState();
_initializeInViewState();
_startListening();
}
@override
void didUpdateWidget(InViewNotifier oldWidget) {
if (oldWidget.throttleDuration != widget.throttleDuration) {
//when throttle duration changes, close the existing stream controller if exists
//and start listening to a stream that is throttled by new duration.
_streamController?.close();
_startListening();
}
super.didUpdateWidget(oldWidget);
}
@override
void dispose() {
_inViewState?.dispose();
_inViewState = null;
_streamController?.close();
super.dispose();
}
void _startListening() {
_streamController = StreamController<ScrollNotification>();
_streamController!.stream
.audit(widget.throttleDuration)
.listen(_inViewState!.onScroll);
}
void _initializeInViewState() {
_inViewState = InViewState(
intialIds: widget.initialInViewIds,
isInViewCondition: widget.isInViewPortCondition,
);
}
@override
Widget build(BuildContext context) {
return InheritedInViewWidget(
inViewState: _inViewState,
child: NotificationListener<ScrollNotification>(
child: widget.child,
onNotification: (ScrollNotification notification) {
late bool isScrollDirection;
//the direction of user scroll up, down, left, right.
final AxisDirection scrollDirection =
notification.metrics.axisDirection;
switch (widget.scrollDirection) {
case Axis.vertical:
isScrollDirection = scrollDirection == AxisDirection.down ||
scrollDirection == AxisDirection.up;
break;
case Axis.horizontal:
isScrollDirection = scrollDirection == AxisDirection.left ||
scrollDirection == AxisDirection.right;
break;
}
final double maxScroll = notification.metrics.maxScrollExtent;
//end of the listview reached
if (isScrollDirection &&
maxScroll - notification.metrics.pixels <=
widget.endNotificationOffset) {
if (widget.onListEndReached != null) {
widget.onListEndReached!();
}
}
//when user is not scrolling
if (notification is UserScrollNotification &&
notification.direction == ScrollDirection.idle) {
if (!_streamController!.isClosed && isScrollDirection) {
_streamController!.add(notification);
}
}
if (!_streamController!.isClosed && isScrollDirection) {
_streamController!.add(notification);
}
return false;
},
),
);
}
}
///The function that defines the area within which the widgets should be notified
///as inView.
typedef bool IsInViewPortCondition(
double deltaTop,
double deltaBottom,
double viewPortDimension,
);

复制代码

使用方法:

child: InViewNotifier(
/定义什么情况算"进入视野"
isInViewPortCondition: (double deltaTop, double deltaBottom, double vpHeight) {
// return deltaTop < (0.5 * vpHeight) && deltaBottom > (0.5 * vpHeight);
//底部不准确 -取 bar 高度
return deltaTop > 0 && deltaBottom < vpHeight -66.h-ScreenUtil().statusBarHeight; //deltaTop < (0.4 * vpHeight);
},
throttleDuration: Duration.zero, //取消延迟
child: RefreshConfiguration(
springDescription: SpringDescription.withDampingRatio(
mass: 1.0, // 减小质量，让物体更轻巧、更容易被拉动
stiffness: 200, // 大幅提升刚度，让回弹更有力、更迅速
ratio: 1.0, // 保持临界阻尼，确保不回弹
),
child: SmartRefresher(
controller: logic.refreshCtrl,
header: const MomentsIndicator(),
// header: const MaterialClassicHeader(color: Color(0xFF041d31)),
footer: IMViews.buildFooter(),
onRefresh: logic.queryWorkingCircleList,
onLoading: logic.loadMore,
// enablePullUp: true,
child: CustomScrollView(

复制代码

ok这样就行了

flutter 使用 inview_notifier_list与pull_to_refresh_plus冲突无法刷新问题

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