Flutter: SearchDelegate Stream is empty when pressing Search

Question

I‘m using a Stream with SearchDelegate.
When I enter something in the search field, it's working fine. But as soon as I press the search symbol, it displays nothing, because the stream is empty. How is that possible?

Here is some code:

List<Notes> notes;

...

void search() {
   showSearch(
     context: context,
     delegate: Search(
         Stream.value(UnmodifiableListView<Note>(notes)).asBroadcastStream()
     )
}


class Search extends SearchDelegate{

   final Stream<UnmodifiableListView<Note>> notes;

   Search(this.notes);

   ...

   @override
   Widget buildResults(BuildContext context){
      return _buildStreamBuilder();
   }


   @override
   Widget buildSuggestions(BuildContext context){
      return _buildStreamBuilder();
   }


   StreamBuilder<UnmodifiableListView<Note>> _buildStreamBuilder() {
     return StreamBuilder< UnmodifiableListView<Note>> (
       stream: notes
       builder: (context, AsyncSnapshot< UnmodifiableListView<Note>>) {
          final results = snapshot.data.where((note){
              ....
   }
}

Why is the stream empty, when buildResults() is called, but not when buildSuggestions() is called?

Solution

Edit in the abstract class SearchDelegate:

void showResults(BuildContext context) {
    _focusNode?.unfocus();
    _currentBody = _SearchBody.results;
 }

Replace:

void showResults(BuildContext context) {
    if(_queryTextController.text.isNotEmpty) {
      _focusNode?.unfocus();
      _currentBody = _SearchBody.results;
    }else{
      _focusNode?.unfocus();
    }
  }

It worked for me

Comments

[Rahul Sharma]

you need to use showResults method api.flutter.dev/flutter/material/SearchDelegate/…