尝试删除列表 react-native expo 中的特定元素

问题描述

伙计们，我正在尝试使用 react-native expo 从列表中删除一个元素 但它一直说 delete_post 不是函数

const ReduceBlogPost = (state,action) => {
  switch (action.type) {
    case 'delete_post':
      return state.filter((blogs) => blogs.id !== action.playload);
    case 'add_Blog_Post':
      return [...state,{ id: Math.floor(Math.random() * 9999),title: `blog number one #${state.length + 1}` }];
    default:
      return state;
  }
};
export const BlogProvider = ({ children }) => {
  const [blogs,dispatch] = useReducer(ReduceBlogPost,[]);
  // updateBlog
  const updateBlog = () => {
    dispatch({ type: 'add_Blog_Post' });
  };
  //delete blog post
  const delete_blog = (dispatch) => {
    return (id) => {
      dispatch({ type: 'delete_post',playload: id });
    };
  };
  return <BlogContext.Provider value={{ data: blogs,updateBlog }}>{children}</BlogContext.Provider>;
};

解决方法

为什么要在 var fragment; //assign default value to fragment override fun onNewIntent(intent: Intent) { super.onNewIntent(intent) // you can add fragment based checks in this method to work as you want if (fragment is YourFragment) { if (intent.getStringExtra("Type") != "START") { //This would be for the first fragment if (personId.text.toString().isEmpty()) { val id = decodeScan((intent)) personId.text = id lockId() } } }else if (fragment is YourSecondFragment) {{ if (productId.hasFocus() || productId.text.isEmpty()) { val res = decodeScan(intent) productId.text = res } else if (locationId.hasFocus() || (locationId.text.isEmpty() && productId.text.isNotEmpty())) { val res = decodeScan(intent) val location = (locations.filter { x -> x.contains(res) }).first() locationId.setText(location) } } } } 函数中传递参数 dispatch？您已经拥有从 delete_blog 取得的 dispatch。 你可以喜欢这个

useReducer

我认为这取决于您的上下文。