I'm trying to fetch data from firestore and display it in a dropdown menu. I tried declaring the list like the following: ? List makes = [''] but I can’t view the data until I click on another field and the dropdown gets populated at multiple occasions. I have it in a method because eventually, I would like to create a second dropdown where there’s a condition in the database query.
ex. If Toyota is selected display all the models for that particular make.
new StreamBuilder<QuerySnapshot>(
stream: Firestore.instance.collection("makesModels").snapshots(),
builder: (context, snapshot) {
if (!snapshot.hasData) return new Text("Please wait");
return new DropdownButton(
items: snapshot.data.documents.map((DocumentSnapshot document) {
return DropdownMenuItem(
value: document.data["make"],
child: new Text(document.data["make"]));
}).toList(),
value: category,
onChanged: (value) {
setState(() {
category = value;
});
},
hint: new Text("Makes"),
style: TextStyle(color: Colors.black),
);
}),
new StreamBuilder<QuerySnapshot>(
stream: Firestore.instance.collection("makesModels").where('make', isEqualTo: category).snapshots(),
builder: (context, snapshot) {
if (!snapshot.hasData) return new Text("Please wait");
return new DropdownButton(
items: snapshot.data.documents.map((DocumentSnapshot document) {
for(int i = 0; i < document.data['models'].length; i++){
print(document.data['models'][i]);
return new DropdownMenuItem(
value: document.data['models'][i],
child: new Text(document.data['models'][i].toString()),
);
}
}).toList(),
value: models,
onChanged: (value) {
print(value);
setState(() {
models = value;
});
},
hint: new Text("Models"),
style: TextStyle(color: Colors.black),
);
}),
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