Mixing
Unable to pass data to new screen on click
0
I've a list of news displayed using card widget and want to show details of corresponding news in new screen when user taps on any news. However, somehow the data I am trying to pass to new screen is null and not sure where the issue is. Error I am getting is:
The getter 'urlToImage' was called on null. If I understand this error correctly, the news object I am passing is returning null but how do I use that object to send actual data using Navigator ?
News model:
class News {
String title;
String description;
String urlToImage;
String content;
News(
this.title,
this.description,
this.urlToImage,
this.content
);
}
Card widget showing image and title of news:
class NewsCard extends StatelessWidget{
final String title, urlToImage;
News news;
NewsCard({this.title,this.urlToImage});
final makeListTile = ListTile(
onTap: () {
Navigator.push(context, MaterialPageRoute(builder: (context) => new Details(news)));
},
contentPadding: EdgeInsets.symmetric(horizontal: 20.0, vertical: 10.0),
leading: Container(
padding: EdgeInsets.only(right: 12.0),
decoration: BoxDecoration(
border: Border(
right: BorderSide(
width: 1.0,
),
),
),
child: Image(
height: 50.0,
width: 50.0,
fit: BoxFit.cover,
image: NetworkImage(urlToImage),
),
),
title: Text(title, style: TextStyle(
fontWeight: FontWeight.bold
)),
trailing: Icon(Icons.keyboard_arrow_right, size: 30.0)
);
return
Card(
shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(15.0)),
elevation: 8.0,
margin: new EdgeInsets.symmetric(horizontal: 10.0, vertical: 6.0),
child: Container(
child: makeListTile,
)
);
}
}
NewsCard class is called as below:
class _NewsClassState extends State<NewsClass> {
final List<NewsCard> _news = <NewsCard>;
Details screen
class Details extends StatelessWidget {
final News news;
Details(this.news);
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('News Details'),
centerTitle: true,
),
body: ListView(
children: <Widget>[
Image.network('${news.urlToImage}',fit: BoxFit.cover,),
Container(
child: Text('${news.content}')
),
]
)
);
}
}
flutter flutter-layout asked Jan 2 at 12:06
DK15DK15
206113
add a comment |
0
I've a list of news displayed using card widget and want to show details of corresponding news in new screen when user taps on any news. However, somehow the data I am trying to pass to new screen is null and not sure where the issue is. Error I am getting is:
The getter 'urlToImage' was called on null. If I understand this error correctly, the news object I am passing is returning null but how do I use that object to send actual data using Navigator ?
News model:
class News {
String title;
String description;
String urlToImage;
String content;
News(
this.title,
this.description,
this.urlToImage,
this.content
);
}
Card widget showing image and title of news:
class NewsCard extends StatelessWidget{
final String title, urlToImage;
News news;
NewsCard({this.title,this.urlToImage});
final makeListTile = ListTile(
onTap: () {
Navigator.push(context, MaterialPageRoute(builder: (context) => new Details(news)));
},
contentPadding: EdgeInsets.symmetric(horizontal: 20.0, vertical: 10.0),
leading: Container(
padding: EdgeInsets.only(right: 12.0),
decoration: BoxDecoration(
border: Border(
right: BorderSide(
width: 1.0,
),
),
),
child: Image(
height: 50.0,
width: 50.0,
fit: BoxFit.cover,
image: NetworkImage(urlToImage),
),
),
title: Text(title, style: TextStyle(
fontWeight: FontWeight.bold
)),
trailing: Icon(Icons.keyboard_arrow_right, size: 30.0)
);
return
Card(
shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(15.0)),
elevation: 8.0,
margin: new EdgeInsets.symmetric(horizontal: 10.0, vertical: 6.0),
child: Container(
child: makeListTile,
)
);
}
}
NewsCard class is called as below:
class _NewsClassState extends State<NewsClass> {
final List<NewsCard> _news = <NewsCard>;
Details screen
class Details extends StatelessWidget {
final News news;
Details(this.news);
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('News Details'),
centerTitle: true,
),
body: ListView(
children: <Widget>[
Image.network('${news.urlToImage}',fit: BoxFit.cover,),
Container(
child: Text('${news.content}')
),
]
)
);
}
}
asked Jan 2 at 12:06
DK15DK15
206113
where you have initialised news object ??
– Ajay Beniwal
Jan 2 at 12:58
I've initialized it insideNewsCardclass asNews news;. @AjayBeniwal
– DK15
Jan 2 at 13:08
2
News news will not initialize it is just a null pointer News references you have to initalise using new keyword the problem you are getting because you are passing null object to the material page route
– Ajay Beniwal
Jan 2 at 13:31
Got it. I am now seeing the data in new screen, although I had to tweak code a bit. @AjayBeniwal
– DK15
Jan 2 at 13:41
add a comment |
0
0
0
I've a list of news displayed using card widget and want to show details of corresponding news in new screen when user taps on any news. However, somehow the data I am trying to pass to new screen is null and not sure where the issue is. Error I am getting is:
The getter 'urlToImage' was called on null. If I understand this error correctly, the news object I am passing is returning null but how do I use that object to send actual data using Navigator ?
News model:
class News {
String title;
String description;
String urlToImage;
String content;
News(
this.title,
this.description,
this.urlToImage,
this.content
);
}
Card widget showing image and title of news:
class NewsCard extends StatelessWidget{
final String title, urlToImage;
News news;
NewsCard({this.title,this.urlToImage});
final makeListTile = ListTile(
onTap: () {
Navigator.push(context, MaterialPageRoute(builder: (context) => new Details(news)));
},
contentPadding: EdgeInsets.symmetric(horizontal: 20.0, vertical: 10.0),
leading: Container(
padding: EdgeInsets.only(right: 12.0),
decoration: BoxDecoration(
border: Border(
right: BorderSide(
width: 1.0,
),
),
),
child: Image(
height: 50.0,
width: 50.0,
fit: BoxFit.cover,
image: NetworkImage(urlToImage),
),
),
title: Text(title, style: TextStyle(
fontWeight: FontWeight.bold
)),
trailing: Icon(Icons.keyboard_arrow_right, size: 30.0)
);
return
Card(
shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(15.0)),
elevation: 8.0,
margin: new EdgeInsets.symmetric(horizontal: 10.0, vertical: 6.0),
child: Container(
child: makeListTile,
)
);
}
}
NewsCard class is called as below:
class _NewsClassState extends State<NewsClass> {
final List<NewsCard> _news = <NewsCard>;
Details screen
class Details extends StatelessWidget {
final News news;
Details(this.news);
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('News Details'),
centerTitle: true,
),
body: ListView(
children: <Widget>[
Image.network('${news.urlToImage}',fit: BoxFit.cover,),
Container(
child: Text('${news.content}')
),
]
)
);
}
}
asked Jan 2 at 12:06
DK15DK15
206113
I've a list of news displayed using card widget and want to show details of corresponding news in new screen when user taps on any news. However, somehow the data I am trying to pass to new screen is null and not sure where the issue is. Error I am getting is:
The getter 'urlToImage' was called on null. If I understand this error correctly, the news object I am passing is returning null but how do I use that object to send actual data using Navigator ?
News model:
class News {
String title;
String description;
String urlToImage;
String content;
News(
this.title,
this.description,
this.urlToImage,
this.content
);
}
Card widget showing image and title of news:
class NewsCard extends StatelessWidget{
final String title, urlToImage;
News news;
NewsCard({this.title,this.urlToImage});
final makeListTile = ListTile(
onTap: () {
Navigator.push(context, MaterialPageRoute(builder: (context) => new Details(news)));
},
contentPadding: EdgeInsets.symmetric(horizontal: 20.0, vertical: 10.0),
leading: Container(
padding: EdgeInsets.only(right: 12.0),
decoration: BoxDecoration(
border: Border(
right: BorderSide(
width: 1.0,
),
),
),
child: Image(
height: 50.0,
width: 50.0,
fit: BoxFit.cover,
image: NetworkImage(urlToImage),
),
),
title: Text(title, style: TextStyle(
fontWeight: FontWeight.bold
)),
trailing: Icon(Icons.keyboard_arrow_right, size: 30.0)
);
return
Card(
shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(15.0)),
elevation: 8.0,
margin: new EdgeInsets.symmetric(horizontal: 10.0, vertical: 6.0),
child: Container(
child: makeListTile,
)
);
}
}
NewsCard class is called as below:
class _NewsClassState extends State<NewsClass> {
final List<NewsCard> _news = <NewsCard>;
Details screen
class Details extends StatelessWidget {
final News news;
Details(this.news);
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('News Details'),
centerTitle: true,
),
body: ListView(
children: <Widget>[
Image.network('${news.urlToImage}',fit: BoxFit.cover,),
Container(
child: Text('${news.content}')
),
]
)
);
}
}
asked Jan 2 at 12:06
DK15DK15
206113
asked Jan 2 at 12:06
DK15DK15
206113
asked Jan 2 at 12:06
DK15DK15
206113
asked Jan 2 at 12:06
DK15DK15
206113
asked Jan 2 at 12:06
DK15DK15
206113
206113
where you have initialised news object ??
– Ajay Beniwal
Jan 2 at 12:58
I've initialized it insideNewsCardclass asNews news;. @AjayBeniwal
– DK15
Jan 2 at 13:08
2
News news will not initialize it is just a null pointer News references you have to initalise using new keyword the problem you are getting because you are passing null object to the material page route
– Ajay Beniwal
Jan 2 at 13:31
Got it. I am now seeing the data in new screen, although I had to tweak code a bit. @AjayBeniwal
– DK15
Jan 2 at 13:41
add a comment |
where you have initialised news object ??
– Ajay Beniwal
Jan 2 at 12:58
I've initialized it insideNewsCardclass asNews news;. @AjayBeniwal
– DK15
Jan 2 at 13:08
2
News news will not initialize it is just a null pointer News references you have to initalise using new keyword the problem you are getting because you are passing null object to the material page route
– Ajay Beniwal
Jan 2 at 13:31
Got it. I am now seeing the data in new screen, although I had to tweak code a bit. @AjayBeniwal
– DK15
Jan 2 at 13:41
where you have initialised news object ??
– Ajay Beniwal
Jan 2 at 12:58
where you have initialised news object ??
– Ajay Beniwal
Jan 2 at 12:58
I've initialized it inside
NewsCard class as News news; . @AjayBeniwal– DK15
Jan 2 at 13:08
I've initialized it inside
NewsCard class as News news; . @AjayBeniwal– DK15
Jan 2 at 13:08
2
2
News news will not initialize it is just a null pointer News references you have to initalise using new keyword the problem you are getting because you are passing null object to the material page route
– Ajay Beniwal
Jan 2 at 13:31
News news will not initialize it is just a null pointer News references you have to initalise using new keyword the problem you are getting because you are passing null object to the material page route
– Ajay Beniwal
Jan 2 at 13:31
Got it. I am now seeing the data in new screen, although I had to tweak code a bit. @AjayBeniwal
– DK15
Jan 2 at 13:41
Got it. I am now seeing the data in new screen, although I had to tweak code a bit. @AjayBeniwal
– DK15
Jan 2 at 13:41
add a comment |
0
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where you have initialised news object ??
– Ajay Beniwal
Jan 2 at 12:58
I've initialized it inside
NewsCardclass asNews news;. @AjayBeniwal– DK15
Jan 2 at 13:08
2
News news will not initialize it is just a null pointer News references you have to initalise using new keyword the problem you are getting because you are passing null object to the material page route
– Ajay Beniwal
Jan 2 at 13:31
Got it. I am now seeing the data in new screen, although I had to tweak code a bit. @AjayBeniwal
– DK15
Jan 2 at 13:41