[英]Updating Parent Component State from Child Component with UseState React Hook
Say I have a parent component like this:假设我有一个这样的父组件:
function Recipe(recipe) {
const [pageState, updatePageState] = useState("view");
return (
<div className="border-b-2 border-gray-300 py-2">
<div className="h-full flex-col md:flex md:flex-row md:justify-between md:items-start">
<div
className="order-2 flex flex-col flex-1 px-2 h-full md:h-72 lg:h-64 md:flex-col md:justify-between md:order-1 md:w-1/2 lg:w-3/4"
>
<RecipeActions pageState = {pageState} triggerParentUpdate = {state => updatePageState(state)} />
</div>
</div>
</div>
)
}
and I have a child component below where I am trying to update pageState
in the parent component.我在下面有一个子组件,我试图在父组件中更新
pageState
。 I've tried several iterations with no luck.我已经尝试了几次迭代,但没有运气。
function RecipeActions(pageState, {triggerParentUpdate}){
const [open, moreActions] = useState(false);
function editRecipe(){
triggerParentUpdate(pageState);
}
return(
<div className="flex">
<span className={`${pageState=='view' ? 'hidden' : ''} ml-1 sm:ml-2 md:ml-1 lg:ml-2 shadow-sm rounded-md`}>
<button
onClick={editRecipe}
type="button"
className="inline-flex items-center px-3 sm:px-4 py-2 border border-gray-300 text-sm leading-5 font-medium rounded-md text-gray-700 bg-white hover:text-gray-500 focus:outline-none focus:shadow-outline-blue focus:border-blue-300 active:text-gray-800 active:bg-gray-50 active:text-gray-800 transition duration-150 ease-in-out"
>
<svg className="h-5 w-5 text-gray-500" fill="currentColor" viewBox="0 0 20 20">
<path d="M17.414 2.586a2 2 0 00-2.828 0L7 10.172V13h2.828l7.586-7.586a2 2 0 000-2.828z" />
<path
fillRule="evenodd"
d="M2 6a2 2 0 012-2h4a1 1 0 010 2H4v10h10v-4a1 1 0 112 0v4a2 2 0 01-2 2H4a2 2 0 01-2-2V6z"
clipRule="evenodd"
/>
</svg>
<p className="hidden sm:block sm:pl-2 md:hidden lg:block">Edit</p>
</button>
</span>
</div>
)
}
I figured it out.我想到了。 See below for a summary:
请参阅下面的摘要:
The important pieces are to make sure that your props are being passed into your child as a single array, you should have a function when calling your function (eg onClick={() => triggerParentUpdate('edit')}
), and when passing your update function to the child from the parent, you need something like this <RecipeActions pageState = {pageState} triggerParentUpdate = {updatePageState} />
重要的部分是确保您的道具作为单个数组传递给您的孩子,在调用 function 时应该有一个 function (例如
onClick={() => triggerParentUpdate('edit')}
),当将您的更新 function 从父级传递给子级,您需要这样的<RecipeActions pageState = {pageState} triggerParentUpdate = {updatePageState} />
Parent家长
function Recipe(recipe) {
const [pageState, setPageState] = useState("view");
const updatePageState = (state) => {
setPageState(state);
}
return (
<div className="border-b-2 border-gray-300 py-2">
<div className="h-full flex-col md:flex md:flex-row md:justify-between md:items-start">
<div
className="order-2 flex flex-col flex-1 px-2 h-full md:h-72 lg:h-64 md:flex-col md:justify-between md:order-1 md:w-1/2 lg:w-3/4"
>
<RecipeActions pageState = {pageState} triggerParentUpdate = {updatePageState} />
</div>
</div>
</div>
)
}
Child孩子
function RecipeActions({pageState, triggerParentUpdate}){
const [open, moreActions] = useState(false);
return(
<div className="flex">
<span className={`${pageState=='view' ? 'hidden' : ''} ml-1 sm:ml-2 md:ml-1 lg:ml-2 shadow-sm rounded-md`}>
<button
onClick={() => triggerParentUpdate('edit')}
type="button"
className="inline-flex items-center px-3 sm:px-4 py-2 border border-gray-300 text-sm leading-5 font-medium rounded-md text-gray-700 bg-white hover:text-gray-500 focus:outline-none focus:shadow-outline-blue focus:border-blue-300 active:text-gray-800 active:bg-gray-50 active:text-gray-800 transition duration-150 ease-in-out"
>
<svg className="h-5 w-5 text-gray-500" fill="currentColor" viewBox="0 0 20 20">
<path d="M17.414 2.586a2 2 0 00-2.828 0L7 10.172V13h2.828l7.586-7.586a2 2 0 000-2.828z" />
<path
fillRule="evenodd"
d="M2 6a2 2 0 012-2h4a1 1 0 010 2H4v10h10v-4a1 1 0 112 0v4a2 2 0 01-2 2H4a2 2 0 01-2-2V6z"
clipRule="evenodd"
/>
</svg>
<p className="hidden sm:block sm:pl-2 md:hidden lg:block">Edit</p>
</button>
</span>
</div>
)
}
and here is another example I saw from this page这是我从这个页面看到的另一个例子
import React from 'react';
function App() {
const [fruits, setFruits] = React.useState([
{ id: '1', name: 'Apple', isFavorite: false },
{ id: '2', name: 'Peach', isFavorite: true },
{ id: '3', name: 'Strawberry', isFavorite: false },
]);
function handleClick(item) {
const newFruits = fruits.map((fruit) => {
if (fruit.id === item.id) {
return {
id: fruit.id,
name: fruit.name,
isFavorite: !fruit.isFavorite,
};
} else {
return fruit;
}
});
setFruits(newFruits);
}
return (
<div>
<h3>with no styling</h3>
<Basket items={fruits} onClick={handleClick} />
</div>
);
}
function Basket({ items, onClick }) {
return (
<ul>
{items.map((item) => (
<li key={item.id}>
{item.name}
<button type="button" onClick={() => onClick(item)}>
{item.isFavorite ? 'Unlike' : 'Like'}
</button>
</li>
))}
</ul>
);
}
export default App;
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.