Myujth

I have a list of objects each with an icon property as shown here:

List<Map<String, String>> _categories = [
 
 'name': 'Sports',
 'icon': 'directions_run',
 ,
 
 'name': 'Politics',
 'icon': 'gavel',
 ,
 
 'name': 'Science',
 'icon': 'wb_sunny',
 ,
];

I then have a widget that I am using inside of a ListView.builder() widget. Currently I am displaying a statically chosen icon to show with the text in my list. My question is how can I use the icon property in my objects to dynamically pick the icon that gets shown for each individual list item?

 Widget _buildCategoryCards(BuildContext context, int index) 
 return Container(
 padding: EdgeInsets.symmetric(vertical: 5.0),
 child: Card(
 child: Container(
 padding: EdgeInsets.all(15.0),
 child: Row(
 children: <Widget>[
 Icon(Icons.directions_run),
 SizedBox(width: 20.0),
 Text(_categories[index]['name']),
 ],
 ),
 ),
 ),
 );
 

Change your List to store an IconData instead of a String:

List<Map<String, IconData>> _categories = [
 
 'name': 'Sports',
 'icon': Icons.directions_run,
 ,
 
 'name': 'Politics',
 'icon': Icons.gavel,
 ,
 
 'name': 'Science',
 'icon': Icons.wb_sunny,
 ,
];

Then, call the IconData from your build method:

 Widget _buildCategoryCards(BuildContext context, int index) 
 return Container(
 padding: EdgeInsets.symmetric(vertical: 5.0),
 child: Card(
 child: Container(
 padding: EdgeInsets.all(15.0),
 child: Row(
 children: <Widget>[
 Icon(_categories[index]['icon']),
 SizedBox(width: 20.0),
 Text(_categories[index]['name']),
 ],
 ),
 ),
 ),
 );
 

Note that this is not useful (even not effecient) to use a Map to do what you want. You should use a custom class:

Class Category 
 String name;
 IconData icon;

 Category(this.name, this.icon);

And then replace your List with this:

List<Category> _categories = [
 Category('Sports', Icons.directions_run),
 Category('Politics', Icons.gavel),
 Category('Science', Icons.wb_sunny),
];

finally in your Widget:

 children: <Widget>[
 Icon(_categories[index].icon),
 SizedBox(width: 20.0),
 Text(_categories[index].name),
 ],

Keep the icon identifier from Icons class in the list instead of storing the text. But if you want to create a mapping from icon label to icon identifier.