Error: The argument type 'String?' can't be assigned to the parameter type 'String' because 'String?' is nullable and 'String' isn't. leading: Image.network(movieItems[index].imageURL),、

这个错误是因为你传递的参数类型不匹配。在Dart语言中，String类型是非空的，而String?类型是可为空的。在这种情况下，你需要将String?类型转换为String类型。你可以使用!操作符将其强制转换为非空值，或者使用??操作符为其指定一个默认值。比如：

leading: Image.network(movieItems[index].imageURL!),

或者

leading: Image.network(movieItems[index].imageURL ?? 'https://example.com/default-image.jpg'),

注意：强制转换为非空值可能会引发空指针异常，因此请确保你的变量不为空。

相关问题

practuce03.dart:8:33: Error: The argument type 'String' can't be assigned to the parameter type 'Uri'. - 'Uri' is from 'dart:core'. var response = await http.get(url); ^

这个错误是因为 http.get() 方法接受的参数类型是 Uri，而你传递的是一个 String 类型的 url。你可以使用 Uri.parse() 方法将 String 类型的 url 转换为 Uri 类型，如下所示：

var url = 'https://example.com';
var uri = Uri.parse(url);
var response = await http.get(uri);

这样就可以解决这个错误了。

Argument of type 'string | null' is not assignable to parameter of type 'string'. Type 'null' is not assignable to type 'string'.

This error message is saying that you are trying to pass a value of type 'string | null' (meaning the variable can be either a string or null) to a function that expects a parameter of type 'string' (meaning the variable must be a string).

The problem is that null is not a valid value for a string parameter, so TypeScript is giving you an error to prevent you from passing null where a string is expected.

To fix this error, you need to make sure that the variable you are passing to the function is always a string and not null. You can do this by checking for null before passing the variable to the function, or by using a non-null assertion operator (!) to tell TypeScript that you are sure the variable is not null.