CODEWITHSUNDEEP
flutterwidgetflutter-dependencies
Abdul Kadhar
Abdul Kadhar

Reputation: 53

How to create common parameter type widget function in flutter

I am creating common parameter type widget function within page class function. But need to create common parameter type widget function which is used to more than one class/page.

                  DropdownSearch<ProductModel>(
                    searchBoxController: TextEditingController(text: ''),
                    mode: Mode.BOTTOM_SHEET,
                    isFilteredOnline: true,
                    showClearButton: true,
                    showSearchBox: true,
                    //label: 'Product Name *',
                    searchBoxDecoration: InputDecoration(
                        hintText:'Search Product',
                        contentPadding: EdgeInsets.fromLTRB(12, 12, 0, 0),
                        border: OutlineInputBorder()
                    ),
                    dropdownSearchDecoration: InputDecoration(
                      hintText:'Select Product',
                      contentPadding: EdgeInsets.fromLTRB(5, 0, 0, 0),
                      hintStyle: TextStyle(fontSize: 12.0),
                    ),
                    emptyBuilder:_customEmptyBuilderProduct,
                    selectedItem:jobLineList[index].productModel,
                    onFind: (String filter) => getProductData(filter),
                    dropdownBuilder: _customDropDownProduct,
                    popupItemBuilder: _customPopupItemBuilderProduct,
                    onChanged: (ProductModel value) {
                      print('onchanged');
                      print(value);
                      if(value == null) {
                      }
                      else {
                      }
                    },
                  ),

_customDropDownProduct is widget function show below,

Widget _customDropDownProduct( BuildContext context, ProductModel item, String itemDesignation) {

    return Container(
      //height: 20.0,
      child: (item?.masterProductName == null)
          ? ListTile(
        contentPadding: EdgeInsets.all(0),
        //leading: CircleAvatar(),
        title: Text("No product selected", style: TextStyle(fontSize: 12.0)),
      )
          : ListTile(
        contentPadding: EdgeInsets.all(0),
        title: Text(item.masterProductName, style: TextStyle(fontSize: 12.0)),
      ),
    );
  }

How to make _customDropDownProduct as common function in flutter.

Getting error like The argument type 'Widget' can't be assigned to the parameter type 'Widget Function(BuildContext, Model, String)'.

Upvotes: 0

Views: 679

Answers (1)

Lulupointu
Lulupointu

Reputation: 3594

I guess you are using _customDropDownProduct() in a dropdownBuilder argument. Instead you should use _customDropDownProduct.

Therefore you won't pass the result of the function (Widget) but the function itself Widget Function(BuildContext, Model, String).

To make it available everywhere you have two options:

  1. Extract the _customDropDownProduct method and make it a global function
  2. Make a CustomDropDownProduct widget and use it in your different screen.

For option 2 here is the code:

The CustomDropDownProduct class:

class CustomDropDownProduct extends StatelessWidget {
  final ProductModel item;
  final String itemDesignation;

  CustomDropDownProduct({Key key, @required this.item, @required this.itemDesignation}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Container(
      //height: 20.0,
      child: (item?.masterProductName == null)
          ? ListTile(
        contentPadding: EdgeInsets.all(0),
        //leading: CircleAvatar(),
        title: Text("No product selected", style: TextStyle(fontSize: 12.0)),
      )
          : ListTile(
        contentPadding: EdgeInsets.all(0),
        title: Text(item.masterProductName, style: TextStyle(fontSize: 12.0)),
      ),
    );
  }
}

How to call it from dropdownBuilder:

dropdownBuilder: (BuildContext context, ProductModel item, String itemDesignation) => 
    CustomDropDownProduct(
        item: item,
        itemDesignation: itemDesignation,
    ),

Upvotes: 1

Related Questions