颤动ontap错误ontap停止工作

Question

在ontap中添加if语句后，颤动按钮停止工作时出现空错误。这是我的颤动代码

import 'package:efood_multivendor/controller/product_controller.dart';
import 'package:efood_multivendor/util/dimensions.dart';
import 'package:flutter/material.dart';
import 'package:get/get_core/src/get_main.dart';
import 'package:get/get_instance/src/extension_instance.dart';
import 'package:get/get_utils/src/extensions/internacionalization.dart';

import 'custom_snackbar.dart';

class QuantityButton extends StatelessWidget {
  final bool isIncrement;
  final Function onTap;
  final int quantity;
  final int stock;
  QuantityButton(
      {@required this.isIncrement,
      @required this.onTap,
      @required this.quantity,
      @required this.stock});

  @override
  Widget build(BuildContext context) {
    return InkWell(
       onTap : onTap({
        if (!isIncrement && quantity > 1) {
          Get.find<ProductController>().setQuantity(false),
        } else if (isIncrement) {
          if (quantity < stock) {
            Get.find<ProductController>().setQuantity(true),
          } else {
            showCustomSnackBar('out_of_stock'.tr),
          }
        }
      }),
      child: Container(
        height: 22,
        width: 22,
        margin: EdgeInsets.symmetric(horizontal: Dimensions.PADDING_SIZE_SMALL),
        decoration: BoxDecoration(
          shape: BoxShape.circle,
          border: Border.all(
              width: 1,
              color: isIncrement
                  ? Theme.of(context).primaryColor
                  : Theme.of(context).disabledColor),
          color: isIncrement
              ? Theme.of(context).primaryColor
              : Theme.of(context).disabledColor.withOpacity(0.2),
        ),
        alignment: Alignment.center,
        child: Icon(
          isIncrement ? Icons.add : Icons.remove,
          size: 15,
          color: isIncrement
              ? Theme.of(context).cardColor
              : Theme.of(context).disabledColor,
        ),
      ),
    );
  }
}

如果我尝试删除if语句并添加按钮，它是工作的，我得到的Another exception was thrown: NoSuchMethodError: '<Unexpected Null Value>'错误仍然按钮不工作

Answer 1

尝试将其包装在一个函数中，以获得清晰的代码。

将，替换为;以结束命令

InkWell(
       onTap : (){
        if (!isIncrement && quantity > 1) {
          Get.find<ProductController>().setQuantity(false);
        } else if (isIncrement) {
          if (quantity < stock) {
            Get.find<ProductController>().setQuantity(true);
          } else {
            showCustomSnackBar('out_of_stock'.tr);
          }
}

祝你好运。