我做了一个表单，在ListView.builder（）中添加图像及其信息，这是图像截图和代码：
class _AddNewProductState extends State<AddNewProduct> {
String? dropdownValue = 'Fruits';
String? productName;
int? productPrice;
Future<void> openMobileImagePicker() async {
final XFile? pickedMobileImage =
await ImagePicker().pickImage(source: ImageSource.gallery);
if (pickedMobileImage != null) {
setState(() {
ImageFiles.mobileImage = File(pickedMobileImage.path);
});
}
}
@override
Widget build(BuildContext context) {
return Scaffold(
body: SafeArea(
child: Padding(
padding: const EdgeInsets.all(15),
child: SingleChildScrollView(
child: Center(
child: Column(
children: [
const Text(
'Add New Product To The Market',
style: TextStyle(
fontWeight: FontWeight.bold,
fontSize: 25,
),
),
Padding(
padding: const EdgeInsets.all(15),
child: Container(
width: double.infinity,
decoration: BoxDecoration(
color: Colors.white,
borderRadius: BorderRadius.circular(30),
boxShadow: const [
BoxShadow(
offset: Offset(0, 10),
blurRadius: 30,
)
],
),
child: Padding(
padding: const EdgeInsets.all(25),
child: Form(
key: UniversalKey.formKey,
child: Column(
children: [
ElevatedButton(
onPressed: () {
setState(() {
openMobileImagePicker();
});
},
child: const Text('Add Product Image'),
),
const SizedBox(
height: 20,
),
Container(
height: 120,
width: 120,
decoration: const BoxDecoration(
boxShadow: [
BoxShadow(
blurRadius: 15,
color: Colors.grey,
)
],
shape: BoxShape.circle,
),
child: CircleAvatar(
backgroundImage: (ImageFiles.mobileImage !=
null)
? Image.file(ImageFiles.mobileImage!,
fit: BoxFit.fill)
.image
: null),
),
const SizedBox(
height: 20,
),
TextFormField(
onSaved: (value) {
setState(() {
ProductDetails.productName = value!;
});
},
decoration: const InputDecoration(
labelText: 'Product Name',
hintText: 'Add Product Name'),
),
const SizedBox(
height: 20,
),
TextFormField(
onSaved: (value) {
setState(() {
ProductDetails.productPrice = value!;
});
},
decoration: const InputDecoration(
labelText: 'Product Price',
hintText: 'Add Product Price'),
),
const SizedBox(
height: 20,
),
DropdownButton<String>(
value: dropdownValue,
items: productCategory,
onChanged: (item) =>
setState(() => dropdownValue = item),
),
const SizedBox(
height: 20,
),
ElevatedButton(
onPressed: () {
listOfProducts.add(
{
'productImage' : ProductDetails.productImage,
'productName' : ProductDetails.productName,
'productPrice' : ProductDetails.productPrice,
'productCategory' : dropdownValue,
}
);
}
,
child: const Text('Add Product!'))
,
const SizedBox(
height: 20,
),
ElevatedButton(onPressed: () {
setState(() {
Navigator.push(context, MaterialPageRoute(builder: (context) => const GroceryPage(),),);
});
}, child: const Text('Go To Hompage'),),
],
),
),
),
),
)
],
),
),
),
),
),
);
}
}当我点击'提交'它应该添加信息在一个ListView.builder（），这是图像截图和代码：
class ProductsListView extends StatelessWidget {
const ProductsListView({
Key? key,
}) : super(key: key);
@override
Widget build(BuildContext context) {
return ListView.builder(
scrollDirection: Axis.horizontal,
itemCount: fruitsList.length,
itemBuilder: (BuildContext context, int index) {
return ClipRect(
child: Container(
width: 140.0,
decoration: BoxDecoration(
borderRadius: BorderRadius.circular(15.0),
color: Colors.white,
boxShadow: const [
BoxShadow(
blurRadius: 10,
color: Colors.black,
),
],
),
margin: const EdgeInsets.all(10.0),
child: Padding(
padding: const EdgeInsets.fromLTRB(20, 10, 10, 10),
child: Column(
children: [
Image.file(
listOfProducts[index]['productImage']
,
height: 80.0,
width: 90.0,
),
const SizedBox(
height: 15,
),
Row(
children: [
Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Text(
listOfProducts[index]['productName'],
style: const TextStyle(
fontSize: 15.0,
fontWeight: FontWeight.bold,
),
),
Text(
listOfProducts[index]['productCategory'],
textAlign: TextAlign.left,
style: const TextStyle(
height: 1.5,
color: kDarkGrey,
fontSize: 12.5,
fontWeight: FontWeight.bold,
),
),
],
),
],
),
Row(
children: [
Text(
listOfProducts[index]['productPrice'],
style: const TextStyle(
fontWeight: FontWeight.bold,
),
),
const Spacer(),
const AddProduct(),
],
)
],
),
),
),
);
},
);
}
}但结果是：
我该怎么修复呢？我试了很多方法都没有成功，我不知道是哪部分代码导致了错误？
相关代码片段：
class ImageFiles {
static File? mobileImage;
static Uint8List? webImage;
}
class ProductDetails {
static File? productImage;
static String? productName;
static String? productPrice;
}
List<Map<String, dynamic>> listOfProducts = [
];
1条答案
按热度按时间xjreopfe1#
由于没有提供
stackTrace，我建议使用调试器或print语句来检查mobileImage的值，看看它在哪里变空，您可以在控制台中使用错误stackTrace来跟踪它。错误的可能原因如下。
您正在使用
ImageFiles类的静态属性来存储用户选择的图像。此属性可能会被覆盖。一个更好的方法是创建类
ImageFiles的示例，初始化它_AddNewProductState并将其传递给ProductsListView小部件。从静态属性切换。
在
_AddNewProductState中，初始化ImageFile并使用该对象。例如：现在将此
ImageFile传递给任何其他小部件，如GroceryPage，或者根据需要将其添加到listOfProducts中。