The feature is to display the profile screen of a user when a specific widget is tapped from a ListView. The way I want to assign each widget with unique ID is to retrieve all IDs from Firebase as an array and create the widgets by iterating through a for loop. Then I add the created widgets to a list and put that list into a ListView. The ListView builds correctly in the application, but I do not know how to add the unique ID's to the widgets in the ListView so that when they are tapped the profile of that widget's ID is retrieve and displayed in a new screen.
I may have the wrong idea about approaching this problem. Because otherwise the IDs will be rendered into the application when the user is using it, which may cause vulnerability issues.
I have tried to use the key property of widgets to store the user unique ID. I also searched the web if there is a way to assign an unique ID to a widget but no luck, or I jam not searching the right way.
enum ScreenStatus {
NOT_DETERMINED,
RETRIEVING_FRIEND_LIST,
FRIEND_LIST_READY,
FRIEND_PROFILE_OPEN
}
class FriendsScreen extends StatefulWidget {
FriendsScreen({this.auth});
final BaseAuth auth;
#override
State<StatefulWidget> createState() => _FriendsScreenState();
}
class _FriendsScreenState extends State<FriendsScreen> {
ScreenStatus screenStatus = ScreenStatus.NOT_DETERMINED;
List _friendList = [];
#override
void initState() {
super.initState();
widget.auth.retrieveUserDocument().then((document) {
document.data.forEach((fieldName, fieldValue) {
setState(() {
if (fieldName == 'friends') {
_friendList = fieldValue;
print(_friendList);
}
screenStatus = _friendList == null
? ScreenStatus.RETRIEVING_FRIEND_LIST
: ScreenStatus.FRIEND_LIST_READY;
});
});
});
}
Widget _createFriendListWidget(List friendList) {
List<Widget> list = List<Widget>();
for (int i = 0; i < friendList.length; i++) {
list.add(
Card(
child: InkWell(
onTap: () {
print('tapped');
},
child: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
ListTile(
leading: Icon(Icons.album),
title: Text(friendList[i]),
subtitle: Text('Subtitle'),
)
],
),
),
),
);
}
return ListView(children: list);
}
Widget _buildFriendList() {
return Scaffold(
body: Container(
child: _createFriendListWidget(_friendList),
),
);
}
Widget _buildWaitingScreen() {
return Scaffold(
body: Container(
alignment: Alignment.center,
child: CircularProgressIndicator(),
),
);
;
}
#override
Widget build(BuildContext context) {
switch (screenStatus) {
case ScreenStatus.NOT_DETERMINED:
return _buildWaitingScreen();
break;
case ScreenStatus.RETRIEVING_FRIEND_LIST:
return _buildWaitingScreen();
break;
case ScreenStatus.FRIEND_LIST_READY:
return _buildFriendList();
break;
default:
return _buildWaitingScreen();
}
}
}
The expected result is to open a new screen of the profile of the user when the widget is tapped with the respective ID of the user.
I don't think you need to identify widgets. Instead you can use user id in onTap closure
Here is how updated _createFriendListWidget could look:
Widget _createFriendListWidget(List friendList) {
List<Widget> list = List<Widget>();
for (int i = 0; i < friendList.length; i++) {
list.add(
Card(
child: ListTile(
leading: Icon(Icons.album),
title: Text(friendList[i]),
subtitle: Text('Subtitle'),
onTap: () {
print("tapped ${friendList[i].id}"); // assume that id is in .id field
}
),
),
);
}
return ListView(children: list);
}
Also note that I've removed Column, because it had only one child so it did not have any effect. And I removed Inkwell because ListView can handle onTap too.
Related
I have a collection called company.
All the companies are going to be stored like in my screenshot.
When I add another company, I want to check if the name already exists or not.
How to perform that?
Here, "Nova" and "Tradetech" are two companies.
When I try to add "Nova" with the field name: "nova" again, I want to show a notice: "Company already exists!".
I have solved this issue with the follwoing code, thanks for helping me!
IN THE FOLLOWING CODE I USED TO FIND
1)A DOCUMENT IS EXISTING OR NOT?
2)A KEY IS EXISTING OR NOT?
3)A VALUE IS EXISTING OR NOT?
SIMPLE METHOD
//////////////////////////////////////////////////////////////////////
import 'package:flutter/material.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'dart:async';
String myText1 = 'temp1';
String myText2 = 'temp2';
String myText3 = 'temp3';
String myText4 = 'temp4';
String myText5 = 'temp5';
String myText6 = 'temp6';
StreamSubscription<DocumentSnapshot> subscription;
final DocumentReference documentReference =
Firestore.instance.document("company/Nova");
class Clean extends StatefulWidget {
#override
_CleanState createState() => _CleanState();
}
class _CleanState extends State<Clean> {
#override
void initState() {
super.initState();
subscription = documentReference.snapshots().listen((datasnapshot) {
//FINDING A SPECIFICDOCUMENT IS EXISTING INSIDE A COLLECTION
if (datasnapshot.exists) {
setState(() {
myText1 = "Document exist";
});
} else if (!datasnapshot.exists) {
setState(() {
myText2 = "Document not exist";
});
}
//FINDING A SPECIFIC KEY IS EXISTING INSIDE A DOCUMENT
if (datasnapshot.data.containsKey("name")) {
setState(() {
myText3 = "key exists";
});
} else if (!datasnapshot.data.containsKey("name")) {
setState(() {
myText4 = "key not exists";
});
}
//FINDING A SPECIFIC VALUE IS EXISTING INSIDE A DOCUMENT
if (datasnapshot.data.containsValue("nova")) {
setState(() {
myText5 = "value exists";
});
} else if (!datasnapshot.data.containsValue("nova")) {
setState(() {
myText6 = "value not exists";
});
}
});
}
#override
Widget build(BuildContext context) {
return Column(
children: <Widget>[
new Text(myText1),
new Text(myText2),
new Text(myText3),
new Text(myText4),
new Text(myText5),
new Text(myText6),
],
);
}
}
MY OLD COMPLEX METHOD BASED ON MY EXISTING CODE
////////////////////////////////////////////////////////
Concept
it has a search bar,when you type it will show the company name ie existing or not in
A Card and a RaisedButton. I am using lower case in Firestore in order to avoid the search error. I have forced the TextFormField output to be lower case with toLowercase(). You can change it to your own text format.
Code
//if the name is not existing it will show a raised button so u can clcik on that to
//go to a COMPANY ADDING PAGE,otherwise it will only show a **CARD** so that you
//can't go to the next page to add your company
//code:
import 'package:flutter/material.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'dart:async';
import './fullscreen.dart';
const blue = 0xFF3b78e7;
String filter = '';
StreamSubscription<DocumentSnapshot> subscription;
final TextEditingController _usercontroller = new TextEditingController();
class CheckAvail extends StatefulWidget {
#override
HomeState createState() => HomeState();
}
class HomeState extends State<CheckAvail> {
#override
Widget build(BuildContext context) {
return Scaffold(
resizeToAvoidBottomPadding: false,
body: Column(
mainAxisAlignment: MainAxisAlignment.start,
children: <Widget>[
// CHILD1
new Flexible(
child: StreamBuilder(
stream: Firestore.instance
.collection('company')
.where('name', isGreaterThanOrEqualTo: filter.toLowerCase())
.limit(1)
.snapshots(),
builder: (BuildContext context,
AsyncSnapshot<QuerySnapshot> snapshot) {
if (!snapshot.hasData) {
return new Column(
children: <Widget>[
new Card(
elevation: 5.0,
child: new Image.asset('assets/progress.gif'),
)
],
);
} else {
return FirestoreListView1(documents: snapshot.data.documents);
}
},
),
),
new Card(
elevation: 0.0,
color: Colors.white,
shape: new RoundedRectangleBorder(
borderRadius: BorderRadius.circular(60.0)),
child: Container(
padding: new EdgeInsets.only(left: 8.0),
child: new TextField(
controller: _usercontroller,
onChanged: (String z) {
setState(() {
filter = z;
});
},
decoration: const InputDecoration(
hintText: "Search...",
hintStyle: TextStyle(
fontFamily: 'roboto',
color: Colors.black38,
fontSize: 16.0,
letterSpacing: -0.500),
fillColor: Colors.white,
border: InputBorder.none,
),
),
),
),
],
),
backgroundColor: Color(blue),
);
}
}
////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class FirestoreListView1 extends StatelessWidget {
final List<DocumentSnapshot> documents;
FirestoreListView1({this.documents});
#override
Widget build(BuildContext context1) {
return ListView.builder(
itemCount: documents.length,
padding: new EdgeInsets.all(1.0),
itemBuilder: (BuildContext context1, int index) {
String name = documents[index].data['name'];
if (name.contains(filter.toLowerCase()) &&
name.length == filter.length) {
return new Container(
padding: new EdgeInsets.only(top: 45.0),
child: new Card(
child: new Text(
"Error:Already a Company Exists with this name\nTry another name")),
);
} else {
return (filter.length >= 1)
? new Container(
padding: new EdgeInsets.only(top: 15.0),
child: new RaisedButton(
onPressed: () => Navigator.push(
context1,
new MaterialPageRoute(
builder: (context1) => new NextPage(
value1: name,
))),
disabledColor: Colors.white,
child: new Text(
"Good!You can use this company name",
),
),
)
: new Container(padding: new EdgeInsets.only(top: 250.0),
child: new Card(child: new Text("CHECK IF YOUR COMPANY NAME \n AVAILABLE OR NOT",style: new TextStyle(fontSize: 20.0),)),
);
}
});
}
}
You can simply use a where query to only receive documents that have that name and then check whether you get documents. Here is an async example method that would perform what you want to know.
Example method
Future<bool> doesNameAlreadyExist(String name) async {
final QuerySnapshot result = await Firestore.instance
.collection('company')
.where('name', isEqualTo: name)
.limit(1)
.getDocuments();
final List<DocumentSnapshot> documents = result.documents;
return documents.length == 1;
}
As you can see, I am only receiving documents, where the name field matches the given name. I also add limit(1) to make sure that I do not unnecessarily retrieve more than 1 document (which would never happen in theory) and then I just check if the length of all documents in the company collection is equal to 1 or not. If it is equal to 1, there already is a company that has that name and otherwise not.
You could also remove the limit(1) and make the check documents.length > 1 and that would work too, but might retrieve unnecessary documents.
Example implementation
#override
Widget build(BuildContext context) {
return FutureBuilder(
future: doesNameAlreadyExist('nova'),
builder: (context, AsyncSnapshot<bool> result) {
if (!result.hasData)
return Container(); // future still needs to be finished (loading)
if (result.data) // result.data is the returned bool from doesNameAlreadyExists
return Text('A company called "Nova" already exists.');
else
return Text('No company called "Nova" exists yet.');
},
);
}
Here, I am not displaying an error message, which would be easily possible with the example method as well. However, the build method of some widget is used. This would e.g. work in a dialog, but I decided to do it to keep it simple and understandable. The FutureBuilder takes in doesNameAlreadyExist, in this case with the name "Nova" from your question and will, in the end, return a Text widget stating whether the name already exists.
Be careful
The where query is case-sensitive. This means that the check would not work if you typed e.g. "noVa" instead of "nova". As this might be important to you, you can make use of this nice method, where you would create an extra field that is insensitive, e.g. all letters are small and then you would simple query like this:
.where('name_insensitive', isEqualTo: name.toLowerCase())
final QuerySnapshot result =
await Firestore.instance.collection('users').where('nickname', isEqualTo:
nickname).getDocuments();
final List < DocumentSnapshot > documents = result.documents;
if (documents.length > 0) {
//exists
} else {
//not exists
}
Use the function:
snapshot.data!.data()!.containsKey('key_name')
to check if a field exists in your document.
PS. I just used this in my code RN and it works
I know I am late.
Posting for future users.
Try this:
DocumentReference datab = db.collection("Company").document("Nova");
datab.get().addOnSuccessListener(new OnSuccessListener<DocumentSnapshot>() {
#Override
public void onSuccess(DocumentSnapshot documentSnapshot) {
if(documentSnapshot.contains("name"))
{
Toast.makeText(YourActivity.this, "Child exixts.", Toast.LENGTH_SHORT).show();
}
else
Toast.makeText(YourActivity.this, "Doesnt exits.", Toast.LENGTH_SHORT).show();
}
});
I want to create a image grid like the instagram search page/profilepage with images in rows of 3 and want the grid to fill up depending on how many imgaes I have in my collection.
When i press the image I want to load that photo so you can save that photo to your phone. I've tried using the wrap function but instead of getting a list with one of every photo i get 152 sets of every photo so the list is huge.
Anyone know what ive done wrong?
And since i want to be able to use onpressed to view the entire photo maybe wrap isn't the function I should use?
Here is a copy of my code:
class Imagepost {
final String img;
Imagepost({this.img});
}
----------------------------------------------------------------
List<Imagepost> _imageListFromSnapshot(QuerySnapshot snapshot) {
return snapshot.documents.map((doc) {
print(doc.data);
return Imagepost(
img: doc.data['img'],
);
}).toList();
}
Stream<List<Imagepost>> get img {
return imageCollection.snapshots().map(_imageListFromSnapshot);
}
-------------------------------------------------------------------
class ImageTile extends StatelessWidget {
final Imagepost img;
ImageTile({this.img});
#override
Widget build(BuildContext context) {
var size = MediaQuery.of(context).size;
return Wrap(
spacing: 1,
runSpacing: 1,
children: List.generate(img.img.length, (index) {
return Container(
width: (size.width-3)/3,
height: (size.width-3)/3,
decoration: BoxDecoration(
image: DecorationImage(
image: NetworkImage(img.img),
fit: BoxFit.cover),
),
);
}),
);
}
}
-------------------------------------------------------------------
class MediaList extends StatefulWidget {
#override
_MediaListState createState() => _MediaListState();
}
class _MediaListState extends State<MediaList> {
#override
Widget build(BuildContext context) {
final imagepost = Provider.of<List<Imagepost>>(context) ?? [];
return ListView.builder(
itemCount: imagepost.length,
itemBuilder: (context, index) {
return ImageTile(img: imagepost[index]);
},
);
}
}
-------------------------------------------------------------
There is a widget called GridView which would be great for that.
GridView.count(
// Create a grid with 3 columns. If you change the scrollDirection to
// horizontal, this produces 3 rows.
crossAxisCount: 3,
// Generate 100 widgets that display their index in the List.
children: List.generate(100, (index) {
return Center(
child: Text(
'Item $index',
style: Theme.of(context).textTheme.headline5,
),
);
}),
)
I am trying to search my sqlite database, right now it returns all the members, even when text is input to the text form. I have a ListView builder in the memberList constructor that creates cards for each member. What I want it to do is display just the cards that match the users input.
i.e. if a user inputs J it would show only the members that either have first or last name with the letters J.
I can see the query is working properly as I have it printing the count in the dbHelper class and it updates each time I make a change to the textform's text. What I need it to do is essentially refresh the body of the Scaffold onChange of the textform's text, which is not working.
Any suggestions on how I can do this?
I prefer to have the textform in the appbar if at all possible.
Below is my code:
import 'package:flutter/material.dart';
import 'package:troop_mobile_app/MemberFiles/Member.dart';
import 'package:troop_mobile_app/MemberFiles/MemberList.dart';
import 'package:troop_mobile_app/DatabaseFiles/DBHelper.dart';
Future<List<Member>> search(String search) async {
var dbHelper = DBHelper();
Future<List<Member>> members = dbHelper.searchScouts(search);
return members;
}
class SearchFunction extends StatefulWidget {
#override
_SearchFunctionState createState() => _SearchFunctionState();
}
class _SearchFunctionState extends State<SearchFunction> {
TextEditingController controller = TextEditingController();
String searchText = "";
_searchResults(String text) {
return new FutureBuilder<List<Member>>(
future: search(text),
builder: (context, snapshot) {
if (snapshot.hasData) {
return MemberList(snapshot.data);
}
return Container(
alignment: AlignmentDirectional.center,
child: new CircularProgressIndicator(
strokeWidth: 7,
));
});
}
Widget build(BuildContext context) {
//Page Creation returning the UI Home Page Display
return Scaffold(
//Top 'Menu Bar' (AppBar) Creation
appBar: AppBar(
leading: IconButton(
icon: Icon(Icons.arrow_back),
onPressed: () {
Navigator.pop(context);
},
padding: EdgeInsets.fromLTRB(
20 /*left*/, 0 /*top*/, 20 /*right*/, 0 /*bottom*/),
),
title: TextField(
//initialValue: 'Search...',
style: TextStyle(color: Colors.black),
decoration: InputDecoration(
//fillColor: Colors.white,
//filled: true,
//border:
//OutlineInputBorder(borderRadius: BorderRadius.circular(12.0)),
labelText: 'Search...',
contentPadding: EdgeInsets.fromLTRB(10, 6, 0, 6),
prefixIcon: Icon(Icons.search),
),
onChanged: (text) async {
_searchResults(text);
searchText = text;
},
controller: controller,
),
),
//End Top 'Menu Bar' Creation
//Main Body Creation
body: Container(
child: new FutureBuilder<List<Member>> (
future: search(searchText),
builder: (context, snapshot) {
if (snapshot.hasData) {
return MemberList(snapshot.data);
}
return Container(
alignment: AlignmentDirectional.center,
child: new CircularProgressIndicator(
strokeWidth: 7,
));
}),
)
//End Main Body Creation
);
}
}
MemberList:
import 'package:flutter/material.dart';
import 'MemberCards.dart';
import 'package:troop_mobile_app/MemberFiles/Member.dart';
class MemberList extends StatelessWidget {
final List<Member> members;
MemberList(this.members);
#override
Widget build(BuildContext context) {
return _buildList(context);
}
ListView _buildList(context) {
return ListView.builder(
itemCount: members.length,
itemBuilder: (context, int) {
return MemberCards(members[int], );
},
);
}
}
DBHelper:
Future<List<Map<String, dynamic>>> searchScoutsMap(String search) async {
Database db = await this.database;
print("This works? $db");
var result = await db.rawQuery("SELECT * FROM $memberTable WHERE adult = 'N' AND ($colFirstName Like '%$search%' OR $colLastName Like '%$search%') ORDER BY $colFirstName ASC, $colLastName ASC");
print("result is working? $result");
print(result.length);
return result;
}
Future<List<Member>> searchScouts(String search) async {
var searchResults = await searchScoutsMap(search); // Get 'Map List' from database
print(searchResults.length);
print(searchResults.toString());
int count = searchResults.length; // Count the number of map entries in db table
List<Member> memberList = List<Member>();
// For loop to create a 'Member List' from a 'Map List'
for (int i = 0; i < count; i++) {
print("for loop working: ${i+1}");
memberList.add(Member.fromMapObject(searchResults[i]));
}
print("completed for loop");
return memberList;
}
I was able to solve my mistake after hours of frustrating work...
Here is was my fix:
In the first code snippet I was missing the setState()
I had to wrap the return new FutureBuilder... with setState()
_searchResults(String text) {
return new FutureBuilder<List<Member>>(
future: search(text),
builder: (context, snapshot) {
if (snapshot.hasData) {
return MemberList(snapshot.data);
}
return Container(
alignment: AlignmentDirectional.center,
child: new CircularProgressIndicator(
strokeWidth: 7,
));
});
}
New code snippet shown below:
I hope this helps anyone else out there that runs into a similar issue.
_searchResults(String text) {
setState(() {
return new FutureBuilder<List<Member>>(
future: search(text),
builder: (context, snapshot) {
if (snapshot.hasData) {
return MemberList(snapshot.data);
}
return Container(
alignment: AlignmentDirectional.center,
child: new CircularProgressIndicator(
strokeWidth: 7,
));
});
});
}
How do I update the color of only the ListTile that is tapped?
Whatever I tried, it just changes the color of all tiles when tap.
How can I retrieve the data and change the color?
class _DesignState extends State<Design> {
var status=0;
var score =0;
Color getContainerColor() {
if (status == 0) {
return Colors.white;
} else if (status == 1) {
return Colors.green;
} else {
return Colors.red;
}
Widget _buildListItem(BuildContext context, DocumentSnapshot data) {
final record = Record.fromSnapshot(data);
final record1= Firestore.instance.collection('creds').document('123').get().then((DocumentSnapshot ds) {
var s =Record.fromSnapshot(ds);
score= s.score;
});
child: ListTile(
title: Text(record.name),
trailing: Text(record.score.toString()),
onTap: () { record.reference.updateData({'score': FieldValue.increment(score)}),
setState(){
status=1;
You're already on the right track, but it looks like you're managing the state of all of your list tile in the same StatefulWidget.
Instead you'll just need to split them up, so that every of your custom ListTile has it's on state. The loading of the data can happen in the parent component of your self build ListTile.
I'll provide you a short example application. The following example is without firebase, but it should be no problem to apply these changes to your application.
You'd simply have to do the data fetching inside the parent component and pass the score parameter of your example to MyListTile – just like the title in the example below.
This is runnablbe on it's own, you can simply copy it into a empty Flutter project:
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
body: Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
MyListTile(title: 'First'),
MyListTile(title: 'Second'),
MyListTile(title: 'Third'),
],
),
),
);
}
}
class MyListTile extends StatefulWidget {
final String title;
MyListTile({this.title});
#override
_MyListTileState createState() => _MyListTileState();
}
class _MyListTileState extends State<MyListTile> {
int status = 0;
get tileColor {
switch(status) {
case 0: {
return Colors.white;
}
case 1: {
return Colors.green;
}
default: {
return Colors.red;
}
}
}
#override
Widget build(BuildContext context) {
return Container(
color: tileColor,
child: ListTile(
title: Text(widget.title),
subtitle: Text('Status: $status'),
onTap: () => setState(() {
status++;
}),
),
);
}
}
I have a collection called company.
All the companies are going to be stored like in my screenshot.
When I add another company, I want to check if the name already exists or not.
How to perform that?
Here, "Nova" and "Tradetech" are two companies.
When I try to add "Nova" with the field name: "nova" again, I want to show a notice: "Company already exists!".
I have solved this issue with the follwoing code, thanks for helping me!
IN THE FOLLOWING CODE I USED TO FIND
1)A DOCUMENT IS EXISTING OR NOT?
2)A KEY IS EXISTING OR NOT?
3)A VALUE IS EXISTING OR NOT?
SIMPLE METHOD
//////////////////////////////////////////////////////////////////////
import 'package:flutter/material.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'dart:async';
String myText1 = 'temp1';
String myText2 = 'temp2';
String myText3 = 'temp3';
String myText4 = 'temp4';
String myText5 = 'temp5';
String myText6 = 'temp6';
StreamSubscription<DocumentSnapshot> subscription;
final DocumentReference documentReference =
Firestore.instance.document("company/Nova");
class Clean extends StatefulWidget {
#override
_CleanState createState() => _CleanState();
}
class _CleanState extends State<Clean> {
#override
void initState() {
super.initState();
subscription = documentReference.snapshots().listen((datasnapshot) {
//FINDING A SPECIFICDOCUMENT IS EXISTING INSIDE A COLLECTION
if (datasnapshot.exists) {
setState(() {
myText1 = "Document exist";
});
} else if (!datasnapshot.exists) {
setState(() {
myText2 = "Document not exist";
});
}
//FINDING A SPECIFIC KEY IS EXISTING INSIDE A DOCUMENT
if (datasnapshot.data.containsKey("name")) {
setState(() {
myText3 = "key exists";
});
} else if (!datasnapshot.data.containsKey("name")) {
setState(() {
myText4 = "key not exists";
});
}
//FINDING A SPECIFIC VALUE IS EXISTING INSIDE A DOCUMENT
if (datasnapshot.data.containsValue("nova")) {
setState(() {
myText5 = "value exists";
});
} else if (!datasnapshot.data.containsValue("nova")) {
setState(() {
myText6 = "value not exists";
});
}
});
}
#override
Widget build(BuildContext context) {
return Column(
children: <Widget>[
new Text(myText1),
new Text(myText2),
new Text(myText3),
new Text(myText4),
new Text(myText5),
new Text(myText6),
],
);
}
}
MY OLD COMPLEX METHOD BASED ON MY EXISTING CODE
////////////////////////////////////////////////////////
Concept
it has a search bar,when you type it will show the company name ie existing or not in
A Card and a RaisedButton. I am using lower case in Firestore in order to avoid the search error. I have forced the TextFormField output to be lower case with toLowercase(). You can change it to your own text format.
Code
//if the name is not existing it will show a raised button so u can clcik on that to
//go to a COMPANY ADDING PAGE,otherwise it will only show a **CARD** so that you
//can't go to the next page to add your company
//code:
import 'package:flutter/material.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'dart:async';
import './fullscreen.dart';
const blue = 0xFF3b78e7;
String filter = '';
StreamSubscription<DocumentSnapshot> subscription;
final TextEditingController _usercontroller = new TextEditingController();
class CheckAvail extends StatefulWidget {
#override
HomeState createState() => HomeState();
}
class HomeState extends State<CheckAvail> {
#override
Widget build(BuildContext context) {
return Scaffold(
resizeToAvoidBottomPadding: false,
body: Column(
mainAxisAlignment: MainAxisAlignment.start,
children: <Widget>[
// CHILD1
new Flexible(
child: StreamBuilder(
stream: Firestore.instance
.collection('company')
.where('name', isGreaterThanOrEqualTo: filter.toLowerCase())
.limit(1)
.snapshots(),
builder: (BuildContext context,
AsyncSnapshot<QuerySnapshot> snapshot) {
if (!snapshot.hasData) {
return new Column(
children: <Widget>[
new Card(
elevation: 5.0,
child: new Image.asset('assets/progress.gif'),
)
],
);
} else {
return FirestoreListView1(documents: snapshot.data.documents);
}
},
),
),
new Card(
elevation: 0.0,
color: Colors.white,
shape: new RoundedRectangleBorder(
borderRadius: BorderRadius.circular(60.0)),
child: Container(
padding: new EdgeInsets.only(left: 8.0),
child: new TextField(
controller: _usercontroller,
onChanged: (String z) {
setState(() {
filter = z;
});
},
decoration: const InputDecoration(
hintText: "Search...",
hintStyle: TextStyle(
fontFamily: 'roboto',
color: Colors.black38,
fontSize: 16.0,
letterSpacing: -0.500),
fillColor: Colors.white,
border: InputBorder.none,
),
),
),
),
],
),
backgroundColor: Color(blue),
);
}
}
////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class FirestoreListView1 extends StatelessWidget {
final List<DocumentSnapshot> documents;
FirestoreListView1({this.documents});
#override
Widget build(BuildContext context1) {
return ListView.builder(
itemCount: documents.length,
padding: new EdgeInsets.all(1.0),
itemBuilder: (BuildContext context1, int index) {
String name = documents[index].data['name'];
if (name.contains(filter.toLowerCase()) &&
name.length == filter.length) {
return new Container(
padding: new EdgeInsets.only(top: 45.0),
child: new Card(
child: new Text(
"Error:Already a Company Exists with this name\nTry another name")),
);
} else {
return (filter.length >= 1)
? new Container(
padding: new EdgeInsets.only(top: 15.0),
child: new RaisedButton(
onPressed: () => Navigator.push(
context1,
new MaterialPageRoute(
builder: (context1) => new NextPage(
value1: name,
))),
disabledColor: Colors.white,
child: new Text(
"Good!You can use this company name",
),
),
)
: new Container(padding: new EdgeInsets.only(top: 250.0),
child: new Card(child: new Text("CHECK IF YOUR COMPANY NAME \n AVAILABLE OR NOT",style: new TextStyle(fontSize: 20.0),)),
);
}
});
}
}
You can simply use a where query to only receive documents that have that name and then check whether you get documents. Here is an async example method that would perform what you want to know.
Example method
Future<bool> doesNameAlreadyExist(String name) async {
final QuerySnapshot result = await Firestore.instance
.collection('company')
.where('name', isEqualTo: name)
.limit(1)
.getDocuments();
final List<DocumentSnapshot> documents = result.documents;
return documents.length == 1;
}
As you can see, I am only receiving documents, where the name field matches the given name. I also add limit(1) to make sure that I do not unnecessarily retrieve more than 1 document (which would never happen in theory) and then I just check if the length of all documents in the company collection is equal to 1 or not. If it is equal to 1, there already is a company that has that name and otherwise not.
You could also remove the limit(1) and make the check documents.length > 1 and that would work too, but might retrieve unnecessary documents.
Example implementation
#override
Widget build(BuildContext context) {
return FutureBuilder(
future: doesNameAlreadyExist('nova'),
builder: (context, AsyncSnapshot<bool> result) {
if (!result.hasData)
return Container(); // future still needs to be finished (loading)
if (result.data) // result.data is the returned bool from doesNameAlreadyExists
return Text('A company called "Nova" already exists.');
else
return Text('No company called "Nova" exists yet.');
},
);
}
Here, I am not displaying an error message, which would be easily possible with the example method as well. However, the build method of some widget is used. This would e.g. work in a dialog, but I decided to do it to keep it simple and understandable. The FutureBuilder takes in doesNameAlreadyExist, in this case with the name "Nova" from your question and will, in the end, return a Text widget stating whether the name already exists.
Be careful
The where query is case-sensitive. This means that the check would not work if you typed e.g. "noVa" instead of "nova". As this might be important to you, you can make use of this nice method, where you would create an extra field that is insensitive, e.g. all letters are small and then you would simple query like this:
.where('name_insensitive', isEqualTo: name.toLowerCase())
final QuerySnapshot result =
await Firestore.instance.collection('users').where('nickname', isEqualTo:
nickname).getDocuments();
final List < DocumentSnapshot > documents = result.documents;
if (documents.length > 0) {
//exists
} else {
//not exists
}
Use the function:
snapshot.data!.data()!.containsKey('key_name')
to check if a field exists in your document.
PS. I just used this in my code RN and it works
I know I am late.
Posting for future users.
Try this:
DocumentReference datab = db.collection("Company").document("Nova");
datab.get().addOnSuccessListener(new OnSuccessListener<DocumentSnapshot>() {
#Override
public void onSuccess(DocumentSnapshot documentSnapshot) {
if(documentSnapshot.contains("name"))
{
Toast.makeText(YourActivity.this, "Child exixts.", Toast.LENGTH_SHORT).show();
}
else
Toast.makeText(YourActivity.this, "Doesnt exits.", Toast.LENGTH_SHORT).show();
}
});