如何消除onDismissible处理程序错误？

Question

我正在尝试使用Dismissible（）从交易列表和应用程序屏幕中删除其中一个交易。但我得到了错误

class TransactionList extends StatefulWidget {
  final List<Transaction> transactions;
  final Function deleteTx;

  TransactionList(this.transactions, this.deleteTx);

  @override
  _TransactionListState createState() => _TransactionListState();
}

class _TransactionListState extends State<TransactionList> {
  @override
  Widget build(BuildContext context) {
    return Container(
      height: 350,
      child: widget.transactions.isEmpty
          ? Column(...
            )
          : ListView.builder(
              itemBuilder: (ctx, index) {
                return Dismissible(
                  key: Key(widget.transactions[index].getId()),
                  onDismissed: (direction) {
                    setState(() {
                      widget.deleteTx;
                    });
                    Scaffold.of(context).showSnackBar(
                      SnackBar(
                          content: Text("${widget.transactions[index].getTitle()} dismissed")),
                    );
                  },
                  background: Container(
                    color: Colors.red,
                  ),
                  child: Card(
                    elevation: 5,
                    margin: EdgeInsets.symmetric(
                      vertical: 8,
                      horizontal: 5,
                    ),
                    child: ListTile(

    //Formatting the amount entered of the transaction 

                      leading: CircleAvatar(
                        ... ,
                          ),
                        ),
                      ),

    //formatting the name/title of the transaction

                      title: Text(
                        ... ,
                      ),

//formatting the date of the transaction
    
                      subtitle: Text(
                        ... ,
                      ),

// adding a delete icon in the transaction card

                      trailing: IconButton(
                        icon: Icon(Icons.delete),
                        color: Theme.of(context).errorColor,
                        onPressed: () =>
                            widget.deleteTx(widget.transactions[index].getId()),
                      ),
                    ),
                  ),
                );
              },
              itemCount: widget.transactions.length,
            ),
    );
  }
}

deletetx只是我的main.dart文件中的一个函数，它删除事务并更改状态。

void _deleteTransaction(String id) {
    setState(() {
      _userTrx.removeWhere((element) {
        return element.getId() == id;
      });
    });
  }

Answer 1

我将上面代码段中的ondisceled()更改为：

onDismissed: (direction) => widget.deleteTx( widget.transactions[index].getId() ),

对我有效。