Related
I m making an app which display a row of images ( All of them using loop / index from 0-4). The code :
for (int i = 0; i <= 3; i++)
child: Card(
semanticContainer: true,
clipBehavior: Clip.antiAliasWithSaveLayer,
child: Container(
width: 300,
height: 300,
color: Colors.accents[i],
child: Image.asset(
"assets/farCryImages/$i.jpg",
alignment: Alignment.center,
fit: BoxFit.cover,
),
),
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(8),
),
elevation: 5,
),
And i wanted to show the user a popup of their name ( i.e : first picture : a , second picture : b etc..). But i can't seem to find a way to do it and I need help.
I tried this but it wont work :
for (int i = 0; i <= 3; i++)
Padding(
padding: const EdgeInsets.fromLTRB(20, 20, 0, 0),
child: GestureDetector(
onLongPress: () => showDialog(
context: context,
builder: (BuildContext context) => AlertDialog(
title: Text("$i"),
),
),
I wanted to change the $i into specific name for specific photos.
Full code :
child: Row(
children: [
for (int i = 0; i <= 3; i++)
Padding(
padding: const EdgeInsets.fromLTRB(20, 20, 0, 0),
child: GestureDetector(
onLongPress: () => showDialog(
context: context,
builder: (BuildContext context) => AlertDialog(
title: Text("$i"),
),
),
child: Card(
semanticContainer: true,
clipBehavior: Clip.antiAliasWithSaveLayer,
child: Container(
width: 300,
height: 300,
color: Colors.accents[i],
child: Image.asset(
"assets/farCryImages/$i.jpg",
alignment: Alignment.center,
fit: BoxFit.cover,
),
),
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(8),
),
elevation: 5,
),
),
)
],
),
Any help is appreciated !!!
I am not sure about your question. However, if you want to loop through different names for images, you should use a string list for their names:
List<String> imageName = [
"first image",
"second image",
// and so on
]
Then, call them in your loop:
onLongPress: () => showDialog(
context: context,
builder: (BuildContext context) => AlertDialog(
title: Text(imageName[i]),
),
),
Also, for better solution, I suggest to use a class for each image:
class ImageItem{
String name;
String path;
// and other parameters like id
// and a constructor
}
Then create a list of this class and use them in your loop.
First of all, Create a Stateful Widget class for the objects of interest like so:
class CardObject extends StatefulWidget {
final String title;
final String image;
final Color color;
const CardObject(this.title, this.image, this.color);
#override
_CardObjectState createState() => _CardObjectState();
}
class _CardObjectState extends State<CardObject> {
#override
Widget build(BuildContext context) {
return Container(
child: Padding(
padding: const EdgeInsets.fromLTRB(20, 20, 0, 0),
child: GestureDetector(
onLongPress: () => showDialog(
context: context,
builder: (BuildContext context) => AlertDialog(
title: Text(widget.title),
),
),
child: Card(
semanticContainer: true,
clipBehavior: Clip.antiAliasWithSaveLayer,
child: Container(
width: 300,
height: 300,
color: widget.color,
child: Image.asset(
"assets/farCryImages/${widget.image}",
alignment: Alignment.center,
fit: BoxFit.cover,
),
),
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(8),
),
elevation: 5,
),
),
),
);
}
}
Then create a list to hold the CardObjects:
//List of CardObjects
final List<CardObject> cardObjects = [
CardObject('title 1', 'image1.jpg', Colors.red),
CardObject('title 2', 'image2.jpg', Colors.blue),
CardObject('title 3', 'image3.jpg', Colors.orange),
CardObject('title 4', 'image4.jpg', Colors.grey),
];
Display your objects like this:
#override
Widget build(BuildContext context) {
return Container(
child: Row(
children: cardObjects,
),
);
}
I am looking to create a grid with 4 custom widgets that can either add or subtract from a given starting number. See image for reference.
For example, if you press player one, the number would increase or decrease to 100 or 99. But the other 3 players would remain the same.
I had originally used one stateful widget with a separate function for each player, but I am sure there's a way to do it in a more modular way.
class CommanderDamage extends StatefulWidget {
#override
State<StatefulWidget> createState() {
return CommanderDamageState();
}
}
class CommanderDamageState extends State<CommanderDamage> {
int damage = 0;
void update() {
setState(() {
damage++;
});
}
#override
Widget build(context) {
return MaterialApp(
home: Scaffold(
body: GridView.builder(
gridDelegate:
SliverGridDelegateWithFixedCrossAxisCount(crossAxisCount: 2),
itemCount: 4,
itemBuilder: (BuildContext context, index) {
return Container(
child: Column(
children: <Widget>[
Text("Player " + index.toString()),
InkWell(
onTap: update,
child: Container(
width: 100.0,
height: 100.0,
child: Text(damage),
)
],
),
);
},
),
),
);
}
}
EDIT: I have edited my code to reflect my current. Currently, when the damage area is pressed, the damage increases for all 4 players instead of the one I am pressing.
Wrap your text widget inside InkWell(). Basically what InkWell does is creates a rectangular touch responsive area.
InkWell(
child: Text(
'Player One',
style: TextStyle(
fontSize: 20, color: Colors.white),
onTap: () {
// Your function
}
)
But this make the interactive tap area according to size of the text which is very small, so it's better to wrap it inside a container and provide height-width or some space with padding
InkWell(
child: Container(
width: 100,
height: 100,
child: Text(
'Player One',
style: TextStyle(
fontSize: 20, color: Colors.white), ),
onTap: () {
// Your function
}
)
An inside onTap you can your function and perform changes.
Read more about InkWell:
https://docs.flutter.io/flutter/material/InkWell-class.html
After lots of trial and error I managed to find an answer.
I had to set the state within the onTap instead of making a separate function and calling it in the onTap.
class CommanderDamage extends StatefulWidget {
int damage = 0;
CommanderDamage({this.damage, Key key});
#override
State<StatefulWidget> createState() {
return CommanderDamageState();
}
}
class CommanderDamageState extends State<CommanderDamage> {
var damage = [0, 0, 0, 0, 0, 0];
#override
Widget build(context) {
return MaterialApp(
home: Scaffold(
body: Column(
crossAxisAlignment: CrossAxisAlignment.center,
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Container(
height: MediaQuery.of(context).size.height,
decoration: BoxDecoration(
gradient: LinearGradient(
begin: Alignment.topLeft, end: Alignment.bottomRight,
colors: [Color(0xfff6921e), Color(0xffee4036)],
),
),
child: GridView.builder(
gridDelegate:
SliverGridDelegateWithFixedCrossAxisCount(crossAxisCount: 2),
itemCount: damage.length,
itemBuilder: (BuildContext context, index) {
return Container(
child: Column(
children: <Widget>[
InkWell(
onTap: () {
setState(() {
damage[index]++;
});
},
onLongPress: () {
setState(() {
damage[index] = 0;
});
},
child: Container(
width: 100.0,
height: 100.0,
child: Text(damage[index].toString()),
),
),
],
),
);
},
),
),
],
),
),
);
}
}
I'm making a new stateful widget that would show a listview according to the option selected, which are ONE and TWO here. The value of index changes once the GestureDetector is tapped, fontsize and color of the text changes. but, the Container with pages[index] does not rebuild
I don't know what is wrong since, one of the container in the column rebuilds and the other doesn't.
#override
State<StatefulWidget> createState() {
// TODO: implement createState
return MatchStatsState();
}
}
class MatchStatsState extends State<MatchStats>{
List<Widget> pages = [
ListView(
scrollDirection: Axis.horizontal,
children: <Widget>[
BattingStatsView(CskBatting),
BowlingStatsView(cskBowling),
],
),
ListView(
scrollDirection: Axis.horizontal,
children: <Widget>[
BattingStatsView(kxipBatting),
BowlingStatsView(kxipBowling)
],
),
];
Color activeColor = Colors.yellow;
Color inactiveColor = Colors.white;
num activeFontSize = 20.0;
num inactiveFontSize = 15.0;
int index = 0;
#override
Widget build(BuildContext context) {
// TODO: implement build
return Container(
height: MediaQuery.of(context).size.height*0.4,
width: MediaQuery.of(context).size.width*0.95,
child: Column(
children: <Widget>[
Container(
height: MediaQuery.of(context).size.height*0.05,
width: MediaQuery.of(context).size.width*0.95,
child: Row(
children: <Widget>[
GestureDetector(
onTap: (){
setState(() {
index = 0;
});
},
child: Container(
width: MediaQuery.of(context).size.width*0.45,
child: Text("ONE",style: TextStyle(color: index == 0?activeColor:inactiveColor,fontSize: index == 0? activeFontSize: inactiveFontSize)),
),
),
GestureDetector(
onTap: (){
setState(() {
index = 1;
});
},
child: Container(
width: MediaQuery.of(context).size.width*0.45,
child: Text("TWO",style: TextStyle(color: index == 1?activeColor:inactiveColor, fontSize: index == 1? activeFontSize: inactiveFontSize)),
),
),
],
),
),
Container(
height: MediaQuery.of(context).size.height*0.35,
width: MediaQuery.of(context).size.width*0.95,
child: pages[index]
),
]
)
);
}
}
I want the second container in the column to rebuild when the value of index changes, how could I achieve that?
Try with this:
create a method that return a List Widget like this:
List<Widget> buildPages() {
return [
ListView(
scrollDirection: Axis.horizontal,
children: <Widget>[
BattingStatsView(CskBatting),
BowlingStatsView(cskBowling),
],
),
ListView(
scrollDirection: Axis.horizontal,
children: <Widget>[
BattingStatsView(kxipBatting),
BowlingStatsView(kxipBowling)
],
),
];
}
Widget getProperWidget(int index) {
return buildPages()[index];
}
Than your column container:
Container(
height: MediaQuery.of(context).size.height*0.35,
width: MediaQuery.of(context).size.width*0.95,
child: getproperWidget(index)
),
Remember to override the initState.
I think the cause of this issue is the element tree doesn't recognize the change that has been done in the widget tree , so you can add Key to the container which holds pages[index] or
you can do something like this :
Widget getWidget(int index){
return Container(
child:pages[index],
);
}
instead of using Container in the widget tree, use a function that will be called every time the ui re renders .
I hope that can help
I am currently using the carousel-slider library to get a carousel in Flutter.
This library is based on a PageView, and in a PageView the elements are centered.
That's the carousel I get:
And this is what I'd like to have:
Here is the code where is use the CarouselSlider:
CarouselSlider(
height: 150,
viewportFraction: 0.5,
initialPage: 0,
enableInfiniteScroll: false,
items: widget.user.lastGamesPlayed.map((game) {
return Builder(
builder: (BuildContext context) {
return Padding(
padding: EdgeInsets.symmetric(horizontal: 10),
child: GestureDetector(
onTap: () {
game.presentGame(context, widget.user);
},
child: ClipRRect(
borderRadius: BorderRadius.all(Radius.circular(25)),
child: Container(
color: Theme.MyColors.lightBlue,
child: Center(
child: Padding(
padding: EdgeInsets.all(20),
child: AutoSizeText(game.name,
style: TextStyle(fontSize: 70),
maxLines: 1)),
),
))));
},
);
}).toList(),
)
And here is the code inside the CarouselSlider library:
#override
Widget build(BuildContext context) {
return getWrapper(PageView.builder(
physics: widget.isScrollEnabled
? AlwaysScrollableScrollPhysics()
: NeverScrollableScrollPhysics(),
scrollDirection: widget.scrollDirection,
controller: widget.pageController,
reverse: widget.reverse,
itemCount: widget.enableInfiniteScroll ? null : widget.items.length,
onPageChanged: (int index) {
int currentPage =
_getRealIndex(index, widget.realPage, widget.items.length);
if (widget.onPageChanged != null) {
widget.onPageChanged(currentPage);
}
},
itemBuilder: (BuildContext context, int i) {
final int index = _getRealIndex(
i + widget.initialPage, widget.realPage, widget.items.length);
return AnimatedBuilder(
animation: widget.pageController,
child: widget.items[index],
builder: (BuildContext context, child) {
// on the first render, the pageController.page is null,
// this is a dirty hack
if (widget.pageController.position.minScrollExtent == null ||
widget.pageController.position.maxScrollExtent == null) {
Future.delayed(Duration(microseconds: 1), () {
setState(() {});
});
return Container();
}
double value = widget.pageController.page - i;
value = (1 - (value.abs() * 0.3)).clamp(0.0, 1.0);
final double height = widget.height ??
MediaQuery.of(context).size.width * (1 / widget.aspectRatio);
final double distortionValue = widget.enlargeCenterPage
? Curves.easeOut.transform(value)
: 1.0;
if (widget.scrollDirection == Axis.horizontal) {
return Center(
child:
SizedBox(height: distortionValue * height, child: child));
} else {
return Center(
child: SizedBox(
width:
distortionValue * MediaQuery.of(context).size.width,
child: child));
}
},
);
},
));
}
How can I prevent elements from being centered?
Thank you in advance
If you don't want to animate page size over scroll there is no need to use this carousel-slider library.
Also, PageView is not the best Widget to achieve the layout you want, you should use a horizontal ListView with PageScrollPhysics.
import 'package:flutter/material.dart';
class Carousel extends StatelessWidget {
Carousel({
Key key,
#required this.items,
#required this.builderFunction,
#required this.height,
this.dividerIndent = 10,
}) : super(key: key);
final List<dynamic> items;
final double dividerIndent;
final Function(BuildContext context, dynamic item) builderFunction;
final double height;
#override
Widget build(BuildContext context) {
return Container(
height: height,
child: ListView.separated(
physics: PageScrollPhysics(),
separatorBuilder: (context, index) => Divider(
indent: dividerIndent,
),
scrollDirection: Axis.horizontal,
itemCount: items.length,
itemBuilder: (context, index) {
Widget item = builderFunction(context, items[index]);
if (index == 0) {
return Padding(
child: item,
padding: EdgeInsets.only(left: dividerIndent),
);
} else if (index == items.length - 1) {
return Padding(
child: item,
padding: EdgeInsets.only(right: dividerIndent),
);
}
return item;
}),
);
}
}
Usage
Carousel(
height: 150,
items: widget.user.lastGamesPlayed,
builderFunction: (context, item) {
return ClipRRect(
borderRadius: BorderRadius.all(Radius.circular(25)),
child: Container(
width: 200,
color: Theme.MyColors.lightBlue,
child: Center(
child: Padding(
padding: EdgeInsets.all(20),
child: AutoSizeText(
item.name,
style: TextStyle(fontSize: 70),
maxLines: 1,
),
),
),
),
);
},
)
UPDATE
As observed by #AdamK, my solution doesn't have the same scroll physics behavior as a PageView, it acts more like a horizontal ListView.
If you are looking for this pagination behavior you should consider to write a custom ScrollPhysics and use it on your scrollable widget.
This is a very well explained article that helps us to achieve the desired effect.
I want to create a list of cards scrolling horizontally with snap to fit effect when swiped either from left or right.
Each card has some spacing between them and fit to screen similar to below image
Apart from that these horizontally scrollable list elements should be contained inside a vertically scrollable list.
I all I am able to achieve is only displaying a list of horizontal scrolling cards after following example in flutter docs.
class SnapCarousel extends StatelessWidget {
#override
Widget build(BuildContext context) {
final title = 'Horizontal List';
return MaterialApp(
title: title,
home: Scaffold(
appBar: AppBar(
title: Text(title),
),
body: Container(
margin: EdgeInsets.symmetric(vertical: 20.0),
height: 200.0,
child: ListView(
scrollDirection: Axis.horizontal,
children: <Widget>[
Container(
width: 160.0,
color: Colors.red,
),
Container(
width: 160.0,
color: Colors.blue,
),
Container(
width: 160.0,
color: Colors.green,
),
Container(
width: 160.0,
color: Colors.yellow,
),
Container(
width: 160.0,
color: Colors.orange,
),
],
),
),
),
);
}
}
Use PageView and ListView:
import 'package:flutter/material.dart';
main() => runApp(MaterialApp(home: MyHomePage()));
class MyHomePage extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Carousel in vertical scrollable'),
),
body: ListView.builder(
padding: EdgeInsets.symmetric(vertical: 16.0),
itemBuilder: (BuildContext context, int index) {
if(index % 2 == 0) {
return _buildCarousel(context, index ~/ 2);
}
else {
return Divider();
}
},
),
);
}
Widget _buildCarousel(BuildContext context, int carouselIndex) {
return Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Text('Carousel $carouselIndex'),
SizedBox(
// you may want to use an aspect ratio here for tablet support
height: 200.0,
child: PageView.builder(
// store this controller in a State to save the carousel scroll position
controller: PageController(viewportFraction: 0.8),
itemBuilder: (BuildContext context, int itemIndex) {
return _buildCarouselItem(context, carouselIndex, itemIndex);
},
),
)
],
);
}
Widget _buildCarouselItem(BuildContext context, int carouselIndex, int itemIndex) {
return Padding(
padding: EdgeInsets.symmetric(horizontal: 4.0),
child: Container(
decoration: BoxDecoration(
color: Colors.grey,
borderRadius: BorderRadius.all(Radius.circular(4.0)),
),
),
);
}
}
Screenshot:
If you don't want to use any 3rd party packages, you can simply try this:
class _HomePageState extends State<HomePage> {
int _index = 0;
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(),
body: Center(
child: SizedBox(
height: 200, // card height
child: PageView.builder(
itemCount: 10,
controller: PageController(viewportFraction: 0.7),
onPageChanged: (int index) => setState(() => _index = index),
itemBuilder: (_, i) {
return Transform.scale(
scale: i == _index ? 1 : 0.9,
child: Card(
elevation: 6,
shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(20)),
child: Center(
child: Text(
"Card ${i + 1}",
style: TextStyle(fontSize: 32),
),
),
),
);
},
),
),
),
);
}
}
this is an old question, and I arrived here looking for something else ;-), but what WitVault was lookig is done easy with this package: https://pub.dev/packages/flutter_swiper
The implementation:
Put the dependencies in pubsec.yaml:
dependencies:
flutter_swiper: ^1.1.6
Import it in the page where you need it:
import 'package:flutter_swiper/flutter_swiper.dart';
In the layout:
new Swiper(
itemBuilder: (BuildContext context, int index) {
return new Image.network(
"http://via.placeholder.com/288x188",
fit: BoxFit.fill,
);
},
itemCount: 10,
viewportFraction: 0.8,
scale: 0.9,
)
To achieve the snap effect via ListView, just set the physics to PageScrollPhysics
const List<Widget> children = [
ContainerCard(),
ContainerCard(),
ContainerCard(),
];
ListView.builder(
scrollDirection: Axis.horizontal,
physics: const PageScrollPhysics(), // this for snapping
itemCount: children.length,
itemBuilder: (_, index) => children[index],
)
Advanced Snap List
If you are looking for advanced usages, such as dynamic item sizes, configurable snap points, visualization of items, and essential control (such as scrollToIndex, animate) you should use the native-based SnappyListView with way more features.
SnappyListView(
itemCount: Colors.accents.length,
itemBuilder: (context, index) {
return Container(
height: 100,
color: Colors.accents.elementAt(index),
child: Text("Index: $index"),
),
);
I believe the answer solution from CopsOnRoad is better and simple for someone who don't want to use a 3rd party library. However, since there is no animation, I add the scale animation when the card is viewed (expand) and the previous card is swiped (shrink) using index. So what happened is whenever the first time the page load, 1st and 2nd card won't have any animation, and when the card is swiped, only the previous and current card have the scale animation. So this is my implementation:
class MyHomePage extends StatefulWidget {
const MyHomePage({super.key, required this.title});
final String title;
#override
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
int currentIndex = -1, previousIndex = 0;
double getAnimationValue(int currentIndex, int widgetIndex, int previousIndex,
{bool begin = true}) {
if (widgetIndex == currentIndex) {
return begin ? 0.9 : 1;
} else {
return begin ? 1 : 0.9;
}
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
SizedBox(
height: 200, // card height
child: PageView.builder(
itemCount: 10,
controller: PageController(viewportFraction: 0.7),
onPageChanged: (int index) {
setState(() {
if (currentIndex != -1) {
previousIndex = currentIndex;
}
currentIndex = index;
});
},
itemBuilder: (_, widgetIndex) {
return (currentIndex != -1 &&
(previousIndex == widgetIndex ||
widgetIndex == currentIndex))
? TweenAnimationBuilder(
duration: const Duration(milliseconds: 400),
tween: Tween<double>(
begin: getAnimationValue(
currentIndex,
widgetIndex,
previousIndex,
),
end: getAnimationValue(
currentIndex,
widgetIndex,
previousIndex,
begin: false,
),
),
builder: (context, value, child) {
return Transform.scale(
scale: value,
child: Card(
elevation: 6,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(20)),
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Text(
"Card${widgetIndex + 1}",
style: const TextStyle(fontSize: 30),
),
Text(
"$widgetIndex >> Widget Index << $widgetIndex",
style: const TextStyle(fontSize: 22),
),
Text(
"$currentIndex >> Current Index << $currentIndex",
style: const TextStyle(fontSize: 22),
),
Text(
"$previousIndex >> Previous Index << $previousIndex",
style: const TextStyle(fontSize: 22),
),
],
),
),
);
},
)
: Transform.scale(
// this is used when you want to disable animation when initialized the page
scale:
(widgetIndex == 0 && currentIndex == -1) ? 1 : 0.9,
child: Card(
elevation: 6,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(20)),
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Text(
"Card${widgetIndex + 1}",
style: const TextStyle(fontSize: 30),
),
Text(
"$widgetIndex >> Widget Index << $widgetIndex",
style: const TextStyle(fontSize: 22),
),
Text(
"$currentIndex >> Init Index << $currentIndex",
style: const TextStyle(fontSize: 22),
),
Text(
"$previousIndex >> Previous Index << $previousIndex",
style: const TextStyle(fontSize: 22),
),
],
),
),
);
},
),
),
],
),
);
}
}
I used TweenAnimationBuilder for this animation and hardcoded the widget. You can use method for your widget or use package flutter_animate for easy animation whenever necessary.