Make ListView from background of the stack scrollable - flutter

I have a Stack that has some containers and horizontal listView at the very bottom of it.(Intentionally, it's a part of design). Now that I'm trying to scroll through it, it doesn't work because top container make it unreachable sort of. How can I remain the same widget tree but make the bottom listView scrollable?
return Stack(
children: <Widget>[
AnimatedBuilder(
animation: ctrl,
builder: (context, child){
var pos = ctrl.position.pixels;
return Container(
height: pos<h?(pos/h * 250):250,
child: ListView.builder(
scrollDirection: Axis.horizontal,
itemBuilder: (ctxt, index){
return Container(
height: pos<h?(pos/h * 250):250,
width: 250,
child: Image(), //Horizontal listview
);
},
),
);
},
),
ListView(
controller: ctrl,
children: <Widget>[
AnimatedBuilder(
animation: ctrl,
builder: (context, child){
var pos = ctrl.position.pixels;
return Container(
height: pos<h?(pos/h * 250):250,
);
},
),
//This is the container I'm talking about, it's just like padding(It's nothing in there)
],
),
],
);

You could put the ListView after the Container in the order inside the Stack, so it will be over the Container and you can interact with it.
Or you could wrap the Container with IgnorePointer, so the gestures won't be intercepted by the Container and you could interact with the ListView.

Related

How to stop listview from overflowing inside a column?

So basically I ListView.builder widget inside of a fixed container.
Container(
height: 500,
child: TabBarView(
children: [
Container(
height: 500,
color: Colors.red,
child: ListView.builder(
shrinkWrap: true,
physics: NeverScrollableScrollPhysics(),
itemCount: 100,
itemBuilder: (context, index) {
return Center(child: Text("This is index $index"));
},
),
),
Center(child: Text("Second Tab")),
Center(child: Text("Third Tab")),
],
),
),
Issue:
The issue with this widget is that since it is inside a container of a fixed height, the content of the list is cut off. I want the list to scroll along with the rest of the page so I don't want to remove the shrinkWrap nor NeverScrollableScrollPhysics(). I want it so that the list takes up as much room as it needs.
Things I've tried:
Wrap the ListView with a Column: this causes the widget to overflow and when I add the SingleChildScrollView around that Column, it removes the functionality of the shrinkWrap and NeverScrollableScrollPhysics().
Checked this answer. The parent widget is actually a CustomScrollView and this widget is inside of a SliverToBoxAdapter. That's why the container has a fixed size in the first place.
What can I do to get the ListView to take up as much room as it want? Thank you!
Wrap your container with SingleChildScrollView and make scrollPhysics
SingleChildScrollView(
Container(
height: 500,
color: Colors.red,
child: ListView.builder(
shrinkWrap: true,
physics: ScrollPhysics(),
itemCount: 100,
itemBuilder: (context, index) {
return Center(child: Text("This is index $index"));
},
),
),
)

Use of Listview.builder makes the screen go away

I want to show Listview underneath my two widgets but when i hot reload, nothing happens and if i run again, UI shows blank screen. If i remove Listview.builder it works fine.
Below is my code.
import 'package:flutter/material.dart';
import 'package:plant_clone/constants.dart';
import 'package:plant_clone/model/model.dart';
import 'package:plant_clone/screens/home/components/header_with_searchbox.dart';
import 'package:plant_clone/screens/home/components/title_with_more_btn.dart';
import 'package:plant_clone/viewmodel/recommended_plants_viewmodel.dart';
class Body extends StatelessWidget {
RecommendedPlantViewModel recommendedPlantViewModel =
new RecommendedPlantViewModel();
#override
Widget build(BuildContext context) {
Size size = MediaQuery.of(context).size;
recommendedPlantViewModel.setWidgetsData();
return SingleChildScrollView(
child: Column(
children: [
HeaderWithSearchBox(size: size),
TitleWithMoreButton(
title: "Recommended",
press: () {},
),
ListView.builder(
scrollDirection: Axis.horizontal,
itemCount: 3,
itemBuilder: (context, index) {
return Card(
child: ListTile(
onTap: (){},
title: Text('Hello'),
),
);
})
],
),
);
}
}
It doesn't look like there's any other way than setting height constraint using a SizedBox that's wrapping a ListView.
Column(
mainAxisSize: MainAxisSize.min,
children: [
SizedBox(
height: size.height,
child: ListView.builder(
...
),
),
],
)
https://flutter.dev/docs/cookbook/lists/horizontal-list
i think it happened because the list view should have a height,,
the esiest way is to test that put it inside a container and give a height to it..
and the second way is wrap the listview inside a Expanded widget and it will fix ..
if not then post the error from debug log
In order to make this to work, you must wrap your ListView with a Container and define the height property as it is part of a Column. You also need to wrap the widget returned by the itemBuilder with a Container and define the width property as the scrollDirection is set to Axis.horizontal.
Container(
height: 100,
child: ListView.builder(
scrollDirection: Axis.horizontal,
itemCount: 3,
itemBuilder: (context, index) {
return Container(
width: 100,
child: Card(
child: ListTile(
onTap: () {},
title: Text('Hello'),
),
),
);
},
),
)

Set Containers array into Stack view Flutter

I am trying to display a ListView Horizontal n times in Stack or Row. But in the end all the ListViews are piled up instead shows one by one from top to bottom.
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Prueba para trabajar en el proyecto"),
),
body: Stack(
children: <Widget>[
_crearLista(),
_crearLista(),
_crearLista(),
_crearLista(),
_crearLista(),
//_crearLoading(),
],
),
);
}
Widget _crearLista() {
return Container(
child: Column(
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
Flexible(
child: Container(
width: MediaQuery.of(context).size.width,
height: MediaQuery.of(context).size.height * 0.25,
decoration: BoxDecoration(),
child: ListView.builder(
scrollDirection: Axis.horizontal,
itemCount: _listaNumeros.length,
itemBuilder: (BuildContext context, int index) {
//return image
},
controller: _scrollController,
),
),
)
],
),
);
}
Any suggestions? please. I want to show all the LsitViews.
A Stack widget puts its children above each other (overlapped or piled up) at the left top corner of the stack by default. Unless you position each child using a Positioned or Align widget. To have all the children one below the other (starting from top of the screen towards bottom), you need to use a Column instead of Stack.
Stack children behave like layers, one covers second, etc.
If you want one child exactly below another, there is ListView and Column

Nested ScrollView inside Slidable panel widget

I have a panel widget that can be dragged vertically in and out from the bottom of the screen. In that panel widget, there is a ListView that is scrollable.
What I'm trying to achieve is, having the panel handle the drag for opening and closing without the nested listview interfering. Once, the panel is open, the listview become scrollable and if the listview is scrolled down while already at the top, the panel handle the gesture instead and closes.
Like so:
I tried to enable/disable scrolling physics on the ListView based on the Panel position but turned out not to be possible that way.
Any ideas ? :)
You can achieve that with DraggableScrollableSheet.
Here is a quick example of how you can use it:
#override
Widget build(BuildContext context) {
return Scaffold(
body: Stack(
children: <Widget>[
Center(child: Text('Some content')),
DraggableScrollableSheet(
minChildSize: 0.2,
initialChildSize: 0.2,
builder: (context, scrollController) => Container(
color: Colors.lightBlueAccent,
child: ListView.builder(
controller: scrollController,
itemCount: 20,
itemBuilder: (context, index) => SizedBox(
height: 200,
child: Text('Item $index'),
),
),
),
),
],
),
);
}

Flutter ListView.Builder() in scrollable Column with other widgets

I have a TabBarView() with an amount of different views. I want of them to be a Column with a TextField at top and a ListView.Builder() below, but both widgets should be in the same scrollable area (scrollview). The way I implemented it threw some errors:
#override
Widget build(BuildContext context) {
return new Column(
mainAxisAlignment: MainAxisAlignment.center,
mainAxisSize: MainAxisSize.max,
children: <Widget>[
new Padding(
padding: EdgeInsets.symmetric(horizontal: 16.0, vertical: 8.0),
child: new TextField(
decoration: new InputDecoration(
hintText: "Type in here!"
),
)
),
new ListView.builder(
itemCount: _posts.length, itemBuilder: _postBuilder)
],
);
}
Error:
I/flutter (23520): The following assertion was thrown during performResize():
I/flutter (23520): Vertical viewport was given unbounded height.
I/flutter (23520): Viewports expand in the scrolling direction to fill their container.In this case, a vertical
I/flutter (23520): viewport was given an unlimited amount of vertical space in which to expand. This situation
I/flutter (23520): typically happens when a scrollable widget is nested inside another scrollable widget.
I/flutter (23520): If this widget is always nested in a scrollable widget there is no need to use a viewport because
I/flutter (23520): there will always be enough vertical space for the children. In this case, consider using a Column
I/flutter (23520): instead. Otherwise, consider using the "shrinkWrap" property (or a ShrinkWrappingViewport) to size
I/flutter (23520): the height of the viewport to the sum of the heights of its children.
I read about stacking the ListView.builder() in an Expanded-Area but it made the textfield kind of "sticky" which is not what I want. :-)
I also came across CustomScrollView but didn't fully understand how to implement it.
Here is the solution:
SingleChildScrollView(
physics: ScrollPhysics(),
child: Column(
children: <Widget>[
Text('Hey'),
ListView.builder(
physics: NeverScrollableScrollPhysics(),
shrinkWrap: true,
itemCount:18,
itemBuilder: (context,index){
return Text('Some text');
})
],
),
),
Placing the ListView inside an Expanded widget should solve your problem:
#override
Widget build(BuildContext context) {
return new Column(
mainAxisAlignment: MainAxisAlignment.center,
mainAxisSize: MainAxisSize.max,
children: <Widget>[
new Padding(
padding: EdgeInsets.symmetric(horizontal: 16.0, vertical: 8.0),
child: new TextField(
decoration: new InputDecoration(
hintText: "Type in here!"
),
)
),
new Expanded(child: ListView.builder(
itemCount: _posts.length, itemBuilder: _postBuilder))
],
);
}
Use SingleChildScrollView which allows the child widget to scroll
Solution
SingleChildScrollView(
child: Column(
children: <Widget>[
ListView.builder(
shrinkWrap: true,
physics: NeverScrollableScrollPhysics(),
Two properties used here
shrinkWrap: true
only occupies the space it needs (it will still scroll when there more items).
physics: NeverScrollableScrollPhysics()
Scroll physics that does not allow the user to scroll. Means only Column+SingleChildScrollView Scrolling work.
Reason for the error:
Column expands to the maximum size in main axis direction (vertical axis), and so does the ListView
Solution
You need to constrain the height of the ListView, so that it does expand to match Column, there are several ways of solving this issue, I'm listing a few here:
If you want to allow ListView to take up all remaining space inside Column use Flexible.
Column(
children: <Widget>[
Flexible(
child: ListView(...),
)
],
)
If you want to limit your ListView to certain height, you can use SizedBox.
Column(
children: <Widget>[
SizedBox(
height: 200, // constrain height
child: ListView(),
)
],
)
If your ListView is small, you may try shrinkWrap property on it.
Column(
children: <Widget>[
ListView(
shrinkWrap: true, // use it
)
],
)
Use physics: NeverScrollableScrollPhysics() and shrinkWrap: true inside ListView.Builder() and enjoy
Here is an efficient solution:
class NestedListExample extends StatelessWidget {
#override
Widget build(BuildContext context) {
return CustomScrollView(
slivers: [
const SliverToBoxAdapter(
child: Text('Header'),
),
SliverList(
delegate: SliverChildBuilderDelegate(
(ctx, index) {
return ListTile(title:Text('Item $index'));
},
),
),
],
);
}
}
Here is a preview on dartpad.
You can use a SliverToBoxAdapter for the other children as only Slivers can be a direct child of a CustomScrollView.
If all the list items are the same height, then you could use SliverFixedExtentList, which is more efficient because the height of each child isn't calculated on the fly, but you will have to know the exact pixel height. You could also use a SliverPrototypeExtentList, where you provide the first item in the list(the prototype), and all the other children will use the height of the prototype so you don't need to know the exact height in pixels.
Use Expanded widget to constrain without overflowing those pixels, :)
Column(
children: <Widget>[
Expanded(
child: ListView(),
),
Expanded(
child: ListView(),
),
],
)
just add
Column(
mainAxisSize: MainAxisSize.max, //Add this line onyour column
children:[
SomeWidget(),
Expanded(child:ListView.builder())
]
)
In my case with a future i did it like this:
SingleChildScrollView(
physics: ScrollPhysics(),
child: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Text("Hey ho let's go!"),
Flexible(
child: FutureBuilder(
future: getData(),
builder: (BuildContext context,
AsyncSnapshot<List<Sale>> snapshot) {
if (snapshot.connectionState != ConnectionState.done ||
snapshot.hasData == null) {
return CircularProgressIndicator();
} else {
data = snapshot.data;
return ListView.builder(
physics: NeverScrollableScrollPhysics(),
shrinkWrap: true,
itemBuilder: (BuildContext context, int index) {
return dataItemWidget(size, data[index], context);
},
itemCount: data.length,
);
}
},
),
),
],
),
),
//If you want Listview.builder inside ListView and want to scroll the parent ListView// //whenever the Items in ListView.builder ends or start you can do it like this
body: ListView(
physics: ScrollPhysics(),
children: [
SizedBox(height: 20),
Container( height: 110.0 *5, // *5 to give size to the container //according to items in the ListView.builder. Otherwise will give hasSize Error
child:ListView.builder(
physics: NeverScrollableScrollPhysics(),
scrollDirection: Axis.vertical,
itemCount: 5,
itemBuilder: (BuildContext context, int indexChild) {
return InkWell(child:Container(height:100));}))
),]),
The best way will be to make the column scrollable by making the column child of SingleChildScrollView and then assigning the same ScrollController to both the SingleChildScrollView and the ListView.builder. This will make the text field and the below ListView as scrollable.
Just add physics: NeverScrollableScrollPhysics() in ListView.builder() so you can scroll
Add physics: NeverScrollableScrollPhysics() inside Listview.builder() method and the nested Listview will scroll
Column is not scrollable, which is why the TextField on top wouldn't scroll but the ListView on the bottom would.
The best way to solve this in my opinion is to make your TextField the first item in your ListView.
So you won't need a column, your parent widget is the ListView, and its children are the TextField followed by the remaining items you build with _postBuilder.
return Column(
children: [
Text("Popular Category"),
Expanded(
child: ListView.builder(`enter code here`
shrinkWrap: false,
scrollDirection: Axis.horizontal,
itemCount: 3,
itemBuilder: (context, index) {
return Row(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Text("hello"),
],
);
}),
),
],
);
body: SingleChildScrollView(
physics: ScrollPhysics(),
child: Column(
children: [
getFiltersOnHomePage(),
SizedBox(
child: StreamBuilder(
stream: FirebaseFirestore.instance.collection('posts').snapshots(),
builder: (context,
AsyncSnapshot<QuerySnapshot<Map<String, dynamic>>> snapshot) {
if (snapshot.connectionState == ConnectionState.waiting) {
return const Center(
child: CircularProgressIndicator(),
);
}
return ListView.builder(
physics: NeverScrollableScrollPhysics(),
shrinkWrap: true,
itemCount: snapshot.data!.docs.length,
itemBuilder: (ctx, index) => Container(
margin: EdgeInsets.symmetric(
horizontal: width > webScreenSize ? width * 0.3 : 0,
vertical: width > webScreenSize ? 15 : 0,
),
child: PostCard(
snap: snapshot.data!.docs[index].data(),
),
));
},
),
),
],
),
),[enter image description here][1]***You will be able to scroll through the page by using Expanded Widget
Blockquote
Using this you can scroll over the entire page. This page includes a row and a listview builder inside a scrollable column.
In my case, I added a Container with transparent color and height up to 270 to solve this one.
Column(
children: <Widget>[
ListView(
shrinkWrap: true, // use it
),
Container(
color: Colors.transparent,
height: 270.0,
),
],
)