"当 ElevatedButton 的 onPressed 运行时未触发 Flutter FutureBuilder"

Question

I'm facing an issue, my FutureBuilder widget is not firing when ElevatedButton's onPress is run.

Within that method I made a call to an http service. So the Future is being setted within onPress.

Here is the ElevatedButton snippet:

 ElevatedButton(
                      style:  ElevatedButton.styleFrom(
                        primary: Colors.red,
                        minimumSize: Size(size.width / 30,size.height / 15),
                        shadowColor: Colors.redAccent,
                        shape:  new RoundedRectangleBorder(
                          borderRadius: new BorderRadius.circular(15.0),
                        )
                      ),
                      onPressed: () {
                          FocusScope.of(context).unfocus();
                
                          _future = _searchRoutes.findProductsByNameAndCity(
                              createFilterProducts(_productNameController.text,
                            _cityNameController.text,
                            _ufController.text,
                            int.parse(_itensPerPageController.text),
                            _orderByController.text),
                            _authScreenRoutes.getLocalJwtToken()
                          );
                        },
                      child: Icon(Icons.search),
                  ),

The method findProductsByNameAndCity() just return a List and it is working.

Here are the FutureBuilder:

Expanded(
                child:  FutureBuilder<List<Product>>(
                    future:  _future,
                    builder:  (context, snapshot) {
                      if(snapshot.hasData){
                        if(snapshot.data!.length <=0){
                          return Container(
                            alignment: Alignment.center,
                            width: size.width,
                            height: size.height,
                            child: setText("Oops, ainda não temos esse produto nessa cidade.", padding / 1.5),
                          );
                        }else{
                          return Padding(
                              padding: sidePadding,
                              child: Container(
                                width: size.width,
                                height: size.height,
                                child: ListView.builder(
                                  itemCount: snapshot.data!.length ,
                                  itemBuilder: (context, index){
                                    return ProductBox(
                                      product: snapshot.data![index],
                                    );
                                  },
                                ),
                              )
                          );
                        }

                      }else if(snapshot.connectionState == ConnectionState.waiting){
                        return Container(
                          alignment: Alignment.center,
                          width: size.width,
                          height: size.height,
                          child: CircularProgressIndicator(),
                        );
                      }else if (!snapshot.hasData){
                        return Container(
                          alignment: Alignment.center,
                          width: size.width,
                          height: size.height,
                          child: setText("Pesquise um produto.", padding / 1.5),
                        );
                      }else{
                        return Container(
                          alignment: Alignment.center,
                          width: size.width,
                          height: size.height,
                          child: CircularProgressIndicator(),
                        );
                      }
                    }
                )
            ),

I know the Http call is working because I debugged and when the breakpoint inside ElevatedButton takes me to inside the method findProductsByNameAndCity() I see the items that i am waiting to receive.

I dont understand why the FutureBuilder does not display the items.

What am I doing wrong?

Answer 1

You missed setState<\/code>

   onPressed: () {
                          FocusScope.of(context).unfocus();
                
                          _future = _searchRoutes.findProductsByNameAndCity(
                              createFilterProducts(_productNameController.text,
                            _cityNameController.text,
                            _ufController.text,
                            int.parse(_itensPerPageController.text),
                            _orderByController.text),
                            _authScreenRoutes.getLocalJwtToken()
                          );
                          setState((){});
                        }