i want to make a dodging (Multiplication) Table...and wanna take input from user from TexteditingController, but i am not able to take the integer value from the Text Editing controller. looking forward if someone would look into it,
TextEditingController num = TextEditingController();
void table() {
print('enter the number $num');
for (var i = 1; i <= 10; i++) {
print('$num*$i = ${num * i}'); //<error>(The operator '*' isn't defined for the type,,'')
}
}
Scaffold(
body: Column(
children: [
TextFormField(
controller: TextEditingController(),
),
Container(
height: 400,
width: 400,
decoration: BoxDecoration(
color: Colors.black,
borderRadius: BorderRadius.circular(20),
),
child: ElevatedButton(
onPressed: table,
child: Text('')),
),
],
));
}
}
The error comes from the fact that you access the TextEditingController directly instead of grabbing the text it contains.
Correct would be:
TextEditingController controller = TextEditingController();
void table() {
var enteredText = controller.text;
var enteredNumber = int.parse(enteredText)
for (var i = 1; i <= 10; i++) {
print('$enteredNumber*$i = ${enteredNumber * i}');
}
}
I'm facing a problem implementing drag and drop in my project. I want dynamically add and delete draggable elements. The problem is that I can't understand how to get the reference to the widget I'm currently moving so that I can understand which coordinates in the list I have to change.
Here is an example of the code where I use the static number of draggable widgets. They are assigned with coordinates from the list. But what if I have to dynamically add and delete those draggable widgets how can I understand which coordinates to change?
So, I have an array of draggble elements and array of coordinates. Widget with index 0 refers to coordinates with index 0. How can I understand which widget I'm currently moving so that I can get the index of it in array of widgets and then change proper coordinates in array of coordinates.
class DragAndDrop extends StatefulWidget {
const DragAndDrop({
Key? key,
this.width,
this.height,
}) : super(key: key);
final double? width;
final double? height;
#override
_DragAndDropState createState() => _DragAndDropState();
}
class _DragAndDropState extends State<DragAndDrop> {
List<double?> _x = [0.0, 20.0];
List<double?> _y = [0.0, 20.0];
int k = -1;
List<Widget> pel = [];
final GlobalKey stackKey = GlobalKey();
#override
Widget build(BuildContext context) {
pel.add(Container(color: Colors.blue));
k++;
Widget drag = Draggable<int>(
data: k,
child: Icon(
Icons.keyboard_arrow_down,
color: Color(0x95000000),
size: 40,
),
feedback: Icon(
Icons.keyboard_arrow_down,
color: Color.fromRGBO(212, 14, 14, 0.584),
size: 40,
),
childWhenDragging: Container(),
onDragStarted: () {},
onDragEnd: (dragDetails) {
setState(() {
final parentPos = stackKey.globalPaintBounds;
if (parentPos == null) return;
if (dragDetails.offset.dx - parentPos.left < 0)
_x[0] = 0;
else if (dragDetails.offset.dx - parentPos.left >
double.parse(widget.width.toString()) - 40)
_x[0] = double.parse(widget.width.toString()) - 40;
else
_x[0] = dragDetails.offset.dx - parentPos.left;
if (dragDetails.offset.dy - parentPos.top < 0)
_y[0] = 0;
else if (dragDetails.offset.dy - parentPos.top >
double.parse(widget.height.toString()) - 40)
_y[0] = double.parse(widget.height.toString()) - 40;
else
_y[0] = dragDetails.offset.dy - parentPos.top;
});
},
);
pel.add(Positioned(
left: _x[0],
top: _y[0],
child: drag,
));
pel.add(Positioned(
left: _x[1],
top: _y[1],
child: Draggable<int>(
data: k,
child: Icon(
Icons.keyboard_arrow_down,
color: Color(0x95000000),
size: 40,
),
feedback: Icon(
Icons.keyboard_arrow_down,
color: Color.fromRGBO(212, 14, 14, 0.584),
size: 40,
),
childWhenDragging: Container(),
onDragStarted: () {},
onDragEnd: (dragDetails) {
setState(() {
final parentPos = stackKey.globalPaintBounds;
if (parentPos == null) return;
_x[1] = dragDetails.offset.dx - parentPos.left; // 11.
_y[1] = dragDetails.offset.dy - parentPos.top;
});
},
),
));
return Stack(
key: stackKey,
fit: StackFit.expand,
children: pel,
);
}
}
extension GlobalKeyExtension on GlobalKey {
Rect? get globalPaintBounds {
final renderObject = currentContext?.findRenderObject();
var translation = renderObject?.getTransformTo(null).getTranslation();
if (translation != null && renderObject?.paintBounds != null) {
return renderObject!.paintBounds
.shift(Offset(translation.x, translation.y));
} else {
return null;
}
}
}
I tried to use a variable that I can assign to Dragble.data field but I'm not able to get it inside the widget.
First of all I don't know what i am facing, but I'll do my best to explain the situation.
I'm trying to build chat app and i have two sections on same page. These two different sections are rendering inside same ListView. Only thing that changing is the data which i am using to feed the ListView. I need to get the status of user in real time so i am putting tagged controllers for each tile which is rendering inside list view. Here comes the problem. The tiles rendered at the same index are not showing the true states of themselves until some state changes on that tile for example position of any Stack item.
Here is the code.
In this part I'm rendering ListView
ListView.builder(
itemCount: chatController.currentChats!.length,
itemBuilder: (context, index) {
return GetBuilder<UserOnlineController>(
global: false,
init: Get.find<UserOnlineController>(tag: chatController.currentUserID == chatController.currentChats![index].user1 ? chatController.currentChats![index].user2 : chatController.currentChats![index].user1),
builder: (userController) {
return Stack(
children: [
Positioned(
child: Container(
color: Colors.black,
width: Get.width,
height: Dimensions.h100,
child: Center(
child: Text(
"${userController.user!.name!}",
style: TextStyle(
color: Colors.white
),
),
),
)
)
],
);
}
);
}),
This is the part that I'm putting controllers and listening chats in real time.
void listenChats() async {
var chatController = Get.find<ChatController>();
var messagesController = Get.find<MessagesController>();
String userID = Get.find<SharedPreferenceService>().getUserID();
var currentUserDoc = (await firestoreService.getCollection('users').where('userID', isEqualTo: userID).get()).docs[0];
Stream<DocumentSnapshot> userStream = firestoreService.getCollection('users').doc(currentUserDoc.id).snapshots();
Stream<QuerySnapshot> chatStream = firestoreService.getCollection('chats').snapshots();
await for(var user in userStream){
var userObject = UserModel.fromJson(user.data() as Map<String,dynamic>);
await for(var chats in chatStream) {
List<Chat> activeChats = [];
List<Chat> unActiveChats = [];
List<Chat> newMatches = [];
List<Chat> allChats = [];
var filteredChats = chats.docs.where((chat) => userObject.chat!.active_chats!.contains(chat['chatID'])).toList();
filteredChats.forEach((chatDoc) {
var currentChat = Chat.fromJson(chatDoc.data() as Map<String,dynamic>);
if(currentChat.user1 == userID){
Get.put(
UserOnlineController(firestoreService: firestoreService, userID: currentChat.user2!),
tag: currentChat.user2!,
);
}
else{
Get.put(
UserOnlineController(firestoreService: firestoreService, userID: currentChat.user1!),
tag: currentChat.user1!
);
}
allChats.add(currentChat);
if(currentChat.isActive!){
if(currentChat.isStarted!){
activeChats.add(currentChat);
}
else{
newMatches.add(currentChat);
}
}
else{
unActiveChats.add(currentChat);
}
});
messagesController.generatePositions(activeChats.length, true);
messagesController.generatePositions(unActiveChats.length, false);
chatController.setAllChats(allChats);
chatController.setCurrentChats();
chatController.setChats(activeChats, unActiveChats, newMatches);
}
}
}
And this is the part that I'm using to control the UI state
void setAllChats(List<Chat> allChats) {
_allChats = allChats;
}
void setCurrentChats() {
_currentChats = _allChats!.where((chat) => chat.isActive! == isActiveMessages).toList();
update();
}
void setIsActiveMessages(bool state){
_isActiveMessages = state;
_currentChats = _allChats!.where((chat) => chat.isActive! == state).toList();
update();
}
In the above pictures all of these users are different but only true one is the third one at second screen shot.
Hello again this question basically explains all the details.
Multiple Instance with GetX tag not working in flutter
Basically you need to add key parameter.
GetBuilder<UserChatController>(
key: Key(currentUserControllerTag),
tag: currentUserControllerTag,
global: false,
init: Get.find<UserChatController>(tag: currentUserControllerTag),
builder: (controller) {
return controller.user != null ? Container(
width: Get.width,
height: Dimensions.h100,
child: Stack(
children: [
Positioned(
left: 0,
right: 0,
child: Container(
height: Dimensions.h100,
width: double.maxFinite,
color: Colors.black,
child:Center(
child: Text(
controller.user != null ? controller.user!.name! : "",
style: TextStyle(
color: Colors.white
),
),
)
))
],
),
) : Container();
},
)
I want to save to Firestore the last slider value after changes. I tried to do that using onChangeEnd, but instead of last value, I get first picked value.
Examples
What I want to get:
Current slider position is 3. I want to press 3 on slider and slide it to 5 because my answer is 5. I want to be saved in Firestore that my answer is 5. After that, it's not possible to move slider and give new answer.
What I am getting #1:
Current slider position is 3. I press 3 on slider and I want to slide it to 5 because I want my answer to be 5. In Firestore is saved that my answer is 3. After that, it's not possible to move slider and give new answer.
What I am getting #2:
Current slider position is 3. I press 5 on slider (without sliding) and I want my answer to be 5. In Firestore is saved that my answer is 5. After that, it's not possible to move slider and give new answer.
import 'package:flutter/material.dart';
import 'package:gamiforms/services/database.dart';
class LinearScale extends StatefulWidget {
String question, formId;
LinearScale(this.question, this.formId);
#override
LinearScaleState createState() => LinearScaleState(question);
}
class LinearScaleState extends State<LinearScale> {
String question;
LinearScaleState(this.question);
double overall = 3.0;
String overallStatus = "Good";
static final formKey = new GlobalKey<FormState>();
DatabaseService databaseService = DatabaseService();
String answer = "";
bool isLoading = false;
bool enabled = true;
uploadFormData(overall) {
//if (formKey.currentState.validate()) {
setState(() {
isLoading = true;
});
print('overall $overall');
if (overall == 1.0) answer = "Fail";
if (overall == 2.0) answer = "Acceptable";
if (overall == 3.0) answer = "Good";
if (overall == 4.0) answer = "Very good";
if (overall == 5.0) answer = "Excellent";
print('answer $answer');
Map<String, String> answerMap = {
"question": this.question,
"answer": answer,
};
print("${widget.formId}");
databaseService.addAnswerData(answerMap, widget.formId).then((value) {
answer = "";
question = this.question;
setState(() {
isLoading = false;
});
}).catchError((e) {
print(e);
});
}
#override
Widget build(BuildContext context) {
var screenSize = MediaQuery.of(context).size;
var width = screenSize.width;
var height = screenSize.height;
print('TEST $question');
return SizedBox(
width: width,
height: height - 100,
child: Container(
margin: EdgeInsets.only(top: 30.0),
child: Column(
crossAxisAlignment: CrossAxisAlignment.stretch,
children: [
Container(
margin: EdgeInsets.only(left: 16.0),
child: Text(
question,
style: TextStyle(fontSize: 20),
)),
Container(
margin: EdgeInsets.symmetric(vertical: 50.0),
child: Text(
overallStatus,
style: TextStyle(
color: Colors.teal[800],
fontWeight: FontWeight.bold,
fontSize: 30.0),
textAlign: TextAlign.center,
),
),
Expanded(
child: Center(
child: Slider(
value: overall,
onChanged: (value) {
setState(() {
overall = value.round().toDouble();
_getOverallStatus(overall);
});
},
onChangeEnd: enabled
? (value) {
enabled = false;
setState(() {
overall = value.round().toDouble();
uploadFormData(overall);
});
}
: null,
label: '${overall.toInt()}',
divisions: 4,
min: 1.0,
max: 5.0,
),
),
)
],
),
),
);
}
_getOverallStatus(double overall) {
switch (overall.toInt()) {
case 1:
overallStatus = 'Fail';
break;
case 2:
overallStatus = 'Acceptable';
break;
case 3:
overallStatus = 'Good';
break;
case 4:
overallStatus = 'Very good';
break;
default:
overallStatus = 'Excellent';
break;
}
}
}
I have a Stateful Widget containing a custom tab view.
At the initialisation of the widget, category data(All, Science, Trending, Health & Fitness here) is fetched from the firestore and accordingly corresponding widgets are added to the tab view.
To add a new category, it can be selected from the last tab('+' here). Inside the corresponding widget, one can select the categories of his interest.
On the tap of "Add Category" button I am adding the selected category to firestore but after that I want to reload the widget and load its initstate(because the category data is fetched in initstate).
Can somone please explain that how can i achieve the same here?
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:firebase_analytics/firebase_analytics.dart';
import 'package:flutter/material.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter_advanced_networkimage/provider.dart';
import 'package:flutter_advanced_networkimage/transition.dart';
import 'package:flutter_staggered_grid_view/flutter_staggered_grid_view.dart';
import 'package:journey_togather/pages/home.dart';
import 'package:journey_togather/pages/invite_friends.dart';
import 'package:journey_togather/pages/journey/create_journey.dart';
import 'package:journey_togather/pages/journey/create_paid_journey.dart';
import 'package:journey_togather/pages/journey/journey_home.dart';
import 'package:journey_togather/pages/locator.dart';
import 'package:journey_togather/services/analytics.dart';
import 'package:journey_togather/settings/appbuilder.dart';
import 'package:journey_togather/settings/sizeconfig.dart';
import 'package:journey_togather/settings/textstyle.dart';
import 'package:journey_togather/widgets/all_user_journey.dart';
import 'package:journey_togather/widgets/pillButton.dart';
import 'package:journey_togather/widgets/progress.dart';
import 'package:uuid/uuid.dart';
class ExploreFeed extends StatefulWidget {
#override
_ExploreFeedState createState() => _ExploreFeedState();
}
class _ExploreFeedState extends State<ExploreFeed>
with TickerProviderStateMixin {
bool isLoading = false;
final AnalyticsService _analyticsService = locator<AnalyticsService>();
TabController tabController;
final _scaffoldKey = GlobalKey<ScaffoldState>();
// this will control the button clicks and tab changing
TabController _controller;
// this will control the animation when a button changes from an off state to an on state
AnimationController _animationControllerOn;
// this will control the animation when a button changes from an on state to an off state
AnimationController _animationControllerOff;
// this will give the background color values of a button when it changes to an on state
Animation _colorTweenBackgroundOn;
Animation _colorTweenBackgroundOff;
// this will give the foreground color values of a button when it changes to an on state
Animation _colorTweenForegroundOn;
Animation _colorTweenForegroundOff;
// when swiping, the _controller.index value only changes after the animation, therefore, we need this to trigger the animations and save the current index
int _currentIndex = 0;
// saves the previous active tab
int _prevControllerIndex = 0;
// saves the value of the tab animation. For example, if one is between the 1st and the 2nd tab, this value will be 0.5
double _aniValue = 0.0;
// saves the previous value of the tab animation. It's used to figure the direction of the animation
double _prevAniValue = 0.0;
List<dynamic> _userInterestCategory = ['All'];
List<dynamic> _userInterestCategoryId = ['All'];
List<Widget> _interestFeedBuild = [];
//saves the newly added interest data of a user from add category tab
List _interestDataId = [];
List _interestDataName = [];
// store the pill buttons for categories in add category page
List<Widget> buttons;
Color _foregroundOn = Colors.white;
Color _foregroundOff = Colors.grey;
// active button's background color
Color _backgroundOn = Colors.green;
// Color _backgroundOff = Colors.black;
Color _backgroundOff = Colors.grey.withOpacity(0.1);
// scroll controller for the TabBar
ScrollController _tabScrollController = new ScrollController();
// this will save the keys for each Tab in the Tab Bar, so we can retrieve their position and size for the scroll controller
List _keys = [];
bool _buttonTap = false;
// ScrollController _scrollController = ScrollController();
#override
void initState() {
setState(() {
isLoading = true;
});
_initialiseData();
// WidgetsBinding.instance.addPostFrameCallback(_initialiseData());
super.initState();
}
_initialiseData()async{
_getInterestData().whenComplete(() {
for (int index = 0; index < _userInterestCategory.length; index++) {
// create a GlobalKey for each Tab
_keys.add(new GlobalKey());
}
// this creates the controller with 6 tabs (in our case)
_controller =
TabController(vsync: this, length: _userInterestCategory.length);
// this will execute the function every time there's a swipe animation
_controller.animation.addListener(_handleTabAnimation);
// this will execute the function every time the _controller.index value changes
_controller.addListener(_handleTabChange);
_animationControllerOff = AnimationController(
vsync: this, duration: Duration(milliseconds: 75));
// so the inactive buttons start in their "final" state (color)
_animationControllerOff.value = 1.0;
_colorTweenBackgroundOff =
ColorTween(begin: _backgroundOn, end: _backgroundOff)
.animate(_animationControllerOff);
_colorTweenForegroundOff =
ColorTween(begin: _foregroundOn, end: _foregroundOff)
.animate(_animationControllerOff);
_animationControllerOn = AnimationController(
vsync: this, duration: Duration(milliseconds: 150));
// so the inactive buttons start in their "final" state (color)
_animationControllerOn.value = 1.0;
_colorTweenBackgroundOn =
ColorTween(begin: _backgroundOff, end: _backgroundOn)
.animate(_animationControllerOn);
_colorTweenForegroundOn =
ColorTween(begin: _foregroundOff, end: _foregroundOn)
.animate(_animationControllerOn);
_userInterestCategoryId.forEach((element) {
if (element != '+') {
_interestFeedBuild.add(
BuildInterestFeed(
categoryId: element,
),
);
} else {
buildButton();
_interestFeedBuild.add(
_buildAddInterest(),
);
}
});
setState(() {
isLoading = false;
});
});
}
#override
void dispose() {
_controller.dispose();
super.dispose();
}
_getInterestData() async {
DocumentSnapshot _doc =
await userInterestsRef.document(currentUser.id).get();
List _interestsFetched = _doc.data['categories'];
_interestsFetched = _interestsFetched.toSet().toList();
Map _userInterestData = {};
for (var val in _interestsFetched) {
Map _filteredData =
globalInterest.firstWhere((element) => element['categoryId'] == val);
_userInterestData[_filteredData['categoryId']] =
(_filteredData['categoryName']);
}
setState(() {
_userInterestCategory =
_userInterestCategory + _userInterestData.values.toList() + ['+'];
_userInterestCategoryId =
_userInterestCategoryId + _userInterestData.keys.toList() + ['+'];
});
}
//tab bar functions
// runs during the switching tabs animation
_handleTabAnimation() {
// gets the value of the animation. For example, if one is between the 1st and the 2nd tab, this value will be 0.5
_aniValue = _controller.animation.value;
// if the button wasn't pressed, which means the user is swiping, and the amount swipped is less than 1 (this means that we're swiping through neighbor Tab Views)
if (!_buttonTap && ((_aniValue - _prevAniValue).abs() < 1)) {
// set the current tab index
_setCurrentIndex(_aniValue.round());
}
// save the previous Animation Value
_prevAniValue = _aniValue;
}
// runs when the displayed tab changes
_handleTabChange() {
// if a button was tapped, change the current index
if (_buttonTap) _setCurrentIndex(_controller.index);
// this resets the button tap
if ((_controller.index == _prevControllerIndex) ||
(_controller.index == _aniValue.round())) _buttonTap = false;
// save the previous controller index
_prevControllerIndex = _controller.index;
}
_setCurrentIndex(int index) {
// if we're actually changing the index
if (index != _currentIndex) {
setState(() {
// change the index
_currentIndex = index;
});
// trigger the button animation
_triggerAnimation();
// scroll the TabBar to the correct position (if we have a scrollable bar)
_scrollTo(index);
}
}
_triggerAnimation() {
// reset the animations so they're ready to go
_animationControllerOn.reset();
_animationControllerOff.reset();
// run the animations!
_animationControllerOn.forward();
_animationControllerOff.forward();
}
_scrollTo(int index) {
// get the screen width. This is used to check if we have an element off screen
double screenWidth = MediaQuery.of(context).size.width;
// get the button we want to scroll to
RenderBox renderBox = _keys[index].currentContext.findRenderObject();
// get its size
double size = renderBox.size.width;
// and position
double position = renderBox.localToGlobal(Offset.zero).dx;
// this is how much the button is away from the center of the screen and how much we must scroll to get it into place
double offset = (position + size / 2) - screenWidth / 2;
// if the button is to the left of the middle
if (offset < 0) {
// get the first button
renderBox = index-1 < 0 ? _keys[0].currentContext.findRenderObject() : _keys[index - 1].currentContext.findRenderObject();
// get the position of the first button of the TabBar
position = renderBox.localToGlobal(Offset.zero).dx;
// if the offset pulls the first button away from the left side, we limit that movement so the first button is stuck to the left side
if (position > offset) offset = position;
} else {
// if the button is to the right of the middle
// get the last button
renderBox = index+1 == _userInterestCategory.length ? _keys[_userInterestCategory.length-1]
.currentContext
.findRenderObject(): _keys[index + 1]
.currentContext
.findRenderObject();
// get its position
position = renderBox.localToGlobal(Offset.zero).dx;
// and size
size = renderBox.size.width;
// if the last button doesn't reach the right side, use it's right side as the limit of the screen for the TabBar
if (position + size < screenWidth) screenWidth = position + size;
// if the offset pulls the last button away from the right side limit, we reduce that movement so the last button is stuck to the right side limit
if (position + size - offset < screenWidth) {
offset = position + size - screenWidth;
}
}
// scroll the calculated amount
_tabScrollController.animateTo(offset + _tabScrollController.offset,
duration: new Duration(milliseconds: 150), curve: Curves.easeInOut);
}
_getBackgroundColor(int index) {
if (index == _currentIndex) {
// if it's active button
return _colorTweenBackgroundOn.value;
} else if (index == _prevControllerIndex) {
// if it's the previous active button
return _colorTweenBackgroundOff.value;
} else {
// if the button is inactive
return _backgroundOff;
}
}
_getForegroundColor(int index) {
// the same as the above
if (index == _currentIndex) {
return _colorTweenForegroundOn.value;
} else if (index == _prevControllerIndex) {
return _colorTweenForegroundOff.value;
} else {
return _foregroundOff;
}
}
callback(Map data) {
if (data['method'] == 'delete') {
setState(() {
_interestDataId.removeWhere((element) => element == data['id']);
_interestDataName.removeWhere((element) => element == data['name']);
});
} else {
setState(() {
_interestDataId.add(data['id']);
_interestDataName.add(data['name']);
});
}
}
addInterest(context) async {
if(_interestDataId.length > 0 && _interestDataName.length > 0) {
await userInterestsRef
.document(currentUser.id)
.updateData({'categories': FieldValue.arrayUnion(_interestDataId)});
Navigator.of(context).pushReplacement(
MaterialPageRoute(
builder: (context) {
return Home();
},
),
);
}
else{
SnackBar snackbar = SnackBar(
content: Text("Please select atleast 1 interest before submitting"),
);
_scaffoldKey.currentState.showSnackBar(snackbar);
}
}
buildButton() {
List<Widget> _buttons = [];
globalInterest.forEach((element) {
if (_userInterestCategoryId.contains(element['categoryId'])) {
} else {
_buttons.add(PillButton(
interestId: element['categoryId'],
interestTitle: element['categoryName'],
callback: callback,
));
}
});
setState(() {
buttons = _buttons;
});
}
Widget _buildAddInterest() {
return Scaffold(
bottomNavigationBar: buttons.length != 0 ?
Container(
margin: EdgeInsets.only(bottom: 16.0),
padding: EdgeInsets.symmetric(horizontal: 16.0),
height: 40,
child: FlatButton(
onPressed: () => addInterest(context),
color: Colors.black,
child: Text(
'Add category',
style: Theme.of(context)
.textTheme
.subtitle2
.copyWith(color: Theme.of(context).primaryColor),
),
),
) : Container(),
body: Padding(
padding: const EdgeInsets.symmetric(horizontal: 16.0),
child: buttons.length != 0
? Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Wrap(
spacing: 12.0,
children: buttons,
),
],
)
: Center(
child: Text(
'Voila! You\'ve selected all the available interests.',
style: Theme.of(context).textTheme.subhead.copyWith(
color:
Theme.of(context).primaryColorDark.withOpacity(0.40),),
// Colors.black,)
),
),
),
);
}
#override
Widget build(BuildContext context) {
return isLoading
? circularProgress(context)
: AppBuilder(
builder: (context){
return Scaffold(
key: _scaffoldKey,
appBar: AppBar(
automaticallyImplyLeading: false,
backgroundColor: Theme.of(context).primaryColor,
elevation: 0,
title: IconButton(
iconSize: SizeConfig.safeBlockHorizontal * 21,
icon: Image.asset(
Theme.of(context).brightness == Brightness.light
? 'assets/images/logo.png'
: 'assets/images/journey_exploreFeed_dark.png',
),
),
titleSpacing: 8.0,
actions: <Widget>[
IconButton(
padding: EdgeInsets.only(right: 24),
icon: new Image.asset(
Theme.of(context).brightness == Brightness.light
? 'assets/icons/create_journey_black.png'
: 'assets/icons/create_journey_white.png'),
onPressed: () {
_analyticsService.logCreateJourneyExploreFeed();
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => CreateJourney()),
);
},
),
IconButton(
padding: EdgeInsets.only(right: 16),
icon:
new Image.asset('assets/icons/invite_friends_icon.png'),
onPressed: () {
_analyticsService.logShareApp();
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => InviteFriends()),
);
},
),
]),
backgroundColor: Colors.transparent,
body: Column(children: <Widget>[
// this is the TabBar
Container(
height: 52.0,
color: Theme.of(context).primaryColor,
// this generates our tabs buttons
child: ListView.builder(
// this gives the TabBar a bounce effect when scrolling farther than it's size
physics: BouncingScrollPhysics(),
controller: _tabScrollController,
// make the list horizontal
scrollDirection: Axis.horizontal,
// number of tabs
itemCount: _userInterestCategory.length,
itemBuilder: (BuildContext context, int index) {
return Padding(
// each button's key
key: _keys[index],
// padding for the buttons
padding: EdgeInsets.fromLTRB(8.0, 4.0, 0.0, 8.0),
child: ButtonTheme(
child: AnimatedBuilder(
animation: _colorTweenBackgroundOn,
builder: (context, child) => FlatButton(
// get the color of the button's background (dependent of its state)
color: _getBackgroundColor(index),
padding:
EdgeInsets.fromLTRB(16.0, 8.0, 16.0, 8.0),
// make the button a rectangle with round corners
shape: RoundedRectangleBorder(
borderRadius:
new BorderRadius.circular(24.0)),
onPressed: () {
setState(() {
_buttonTap = true;
// trigger the controller to change between Tab Views
_controller.animateTo(index);
// set the current index
_setCurrentIndex(index);
// scroll to the tapped button (needed if we tap the active button and it's not on its position)
_scrollTo(index);
});
},
child: index !=
_userInterestCategory.length - 1
? Text(
// get the icon
_userInterestCategory[index],
// get the color of the icon (dependent of its state)
style: (TextStyle(
color: _getForegroundColor(index),
)),
)
: Icon(
Icons.add,
color: _getForegroundColor(index),
)),
)));
})),
Flexible(
// this will host our Tab Views
child: TabBarView(
// and it is controlled by the controller
controller: _controller,
children: _interestFeedBuild,
)),
]));
},
);
}
}
class BuildInterestFeed extends StatefulWidget {
final String categoryId;
BuildInterestFeed({this.categoryId});
#override
_BuildInterestFeedState createState() => _BuildInterestFeedState();
}
class _BuildInterestFeedState extends State<BuildInterestFeed>
with AutomaticKeepAliveClientMixin {
bool isLoading = false;
List<Journey> journeys = [];
final AnalyticsService _analyticsService = locator<AnalyticsService>();
String docId = Uuid().v4();
List<DocumentSnapshot> journeysFetched = []; // stores fetched products
bool hasMore = true; // flag for more products available or not
int documentLimit = 10; // documents to be fetched per request
DocumentSnapshot
lastDocument; // flag for last document from where next 10 records to be fetched
ScrollController _verticalScrollController = ScrollController();
#override
void initState() {
super.initState();
if (widget.categoryId != '+') {
_getExploreFeedData();
_verticalScrollController.addListener(() {
double maxScroll = _verticalScrollController.position.maxScrollExtent;
double currentScroll = _verticalScrollController.position.pixels;
double delta = MediaQuery.of(context).size.height * 0.10;
if (maxScroll - currentScroll <= delta) {
_getExploreFeedData();
}
});
}
}
_getExploreFeedData() async {
if (!hasMore) {
print('No More Journeys');
return;
}
if (isLoading) {
return;
}
setState(() {
isLoading = true;
});
if (widget.categoryId == 'All') {
await buildAllDataFeed();
} else {
QuerySnapshot querySnapshot;
if (lastDocument == null) {
querySnapshot = await journeyRef
.orderBy('createdAt', descending: true)
.where('category', arrayContains: widget.categoryId)
.limit(documentLimit)
.getDocuments();
} else {
querySnapshot = await journeyRef
.orderBy('createdAt', descending: true)
.where('category', arrayContains: widget.categoryId)
.startAfterDocument(lastDocument)
.limit(documentLimit)
.getDocuments();
}
if (querySnapshot.documents.length != 0) {
if (querySnapshot.documents.length < documentLimit) {
hasMore = false;
}
if (querySnapshot.documents.length != 0) {
lastDocument =
querySnapshot.documents[querySnapshot.documents.length - 1];
} else {
lastDocument = null;
}
journeysFetched.addAll(querySnapshot.documents);
}
}
setState(() {
isLoading = false;
});
}
buildAllDataFeed() async {
QuerySnapshot querySnapshot;
if (lastDocument == null) {
querySnapshot = await journeyRef
.orderBy('createdAt', descending: true)
.limit(documentLimit)
.getDocuments();
} else {
querySnapshot = await journeyRef
.orderBy('createdAt', descending: true)
.startAfterDocument(lastDocument)
.limit(documentLimit)
.getDocuments();
}
if (querySnapshot.documents.length < documentLimit) {
hasMore = false;
}
if (querySnapshot.documents.length != 0) {
lastDocument =
querySnapshot.documents[querySnapshot.documents.length - 1];
} else {
lastDocument = null;
}
// lastDocument = querySnapshot.documents[querySnapshot.documents.length - 1];
journeysFetched.addAll(querySnapshot.documents);
}
addInterestData({tags}) async{
userInterestsRef.document(currentUser.id).updateData({
'tags': FieldValue.arrayUnion(tags),
});
}
#override
bool get wantKeepAlive => true;
#override
Widget build(BuildContext context) {
super.build(context);
return
RefreshIndicator(
onRefresh: () => _getExploreFeedData(),
child:
Scaffold(
body: Padding(
padding: const EdgeInsets.symmetric(horizontal: 8.0),
child: Column(children: [
Expanded(
child: journeysFetched.length == 0
? Center(
child: Text(
'There\'s nothing new here right now',
style: Theme.of(context).textTheme.subhead.copyWith(
color: Theme.of(context)
.primaryColorDark
.withOpacity(0.40)),
),
)
: StaggeredGridView.countBuilder(
controller: _verticalScrollController,
crossAxisCount: 2,
itemCount: journeysFetched.length,
itemBuilder: (BuildContext context, int index) {
Map journeyData = journeysFetched.elementAt(index).data;
String journeyId =
journeysFetched.elementAt(index).documentID;
return GestureDetector(
child: Container(
child: Column(
mainAxisSize: MainAxisSize.min,
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
TransitionToImage(
transitionType: TransitionType.fade,
borderRadius: BorderRadius.circular(8.0),
loadingWidget: Container(
height: 242,
decoration: (BoxDecoration(
borderRadius:
BorderRadius.circular(8.0),
color: Theme.of(context)
.primaryColorLight
.withOpacity(0.05),
))),
image: AdvancedNetworkImage(
journeyData['coverImage'],
useDiskCache: true,
cacheRule: CacheRule(
maxAge: Duration(hours: 9999))),
),
Padding(
padding: EdgeInsets.only(
top: SizeConfig.safeBlockVertical * 0.5,
left:
SizeConfig.safeBlockVertical * 0.5),
child: Text(
journeyData['title'],
style: Theme.of(context)
.textTheme
.bodyText2
.copyWith(
fontWeight: FontWeight.w500),
))
],
),
),
onTap: () {
addInterestData(
tags: journeyData['community']['hashtags']);
Navigator.push(
context,
MaterialPageRoute(
settings:
RouteSettings(name: 'journey_home'),
builder: (context) =>
JourneyHome(journeyId: journeyId)));
});
},
staggeredTileBuilder: (int index) => StaggeredTile.fit(1),
mainAxisSpacing: SizeConfig.safeBlockVertical * 2,
crossAxisSpacing: 8.0,
),
),
isLoading ? circularProgress(context) : Container()
]),
),
),
);
}
}
There is also a pub package named states_rebuilder
https://pub.dev/packages/states_rebuilder
or
our Widget should have a setState() method, this method is called, the widget is redrawn