当我试图进入反应时,我开始了一个项目并卡住了。也许有人可以帮助我找到这个问题。波纹管我解释了该应用应该做什么。
用户在 searchbar.jsx 的内部输入框中键入查询搜索栏组件将 QUERY 传递给 app.jsx 并启动fetchphotos函数,该功能启动了API请求。
要整理分页,app.jsx imports pagination.jsx ,它计算响应中的图片数并显示分页按钮。
上述作品。
但是现在,如果您单击"分页"按钮,则应将分页组件的 page 的值传递到app.jsx,然后将其传递给fetchphotos函数(运行API请求)。
)。我猜问题是 page 的值永远不会找到app.jsx,因此API请求缺少页面的值。
我花了几个小时,但由于缺乏知识,找不到方法来修复它。您能把我指向正确的方向,并向我展示代码有什么问题?
app.jsx
import React, { Component } from "react";
import axios from "axios";
import Pagination from "../Pagination";
import SearchBar from "../SearchBar";
import ListItem from "../ListItem";
import "./app.scss";
class App extends Component {
state = {
photos: [],
totalPhotos: 0,
perPage: 30,
currentPage: 1,
query: null
};
componentDidMount() {
this.fetchPhotos("gorilla", this.state.currentPage);
}
fetchPhotos = (inputValue, page) => {
const baseUrl = "https://api.unsplash.com/search/photos";
const options = {
headers: {
Authorization: `Client-ID ${process.env.REACT_APP_UNSPLASH_API_KEY}`
},
params: {
query: inputValue,
page: this.state.page,
per_page: this.state.perPage
}
};
axios
.get(baseUrl, options)
.then(response => {
this.setState({
photos: response.data.results,
totalPhotos: parseInt(response.headers["x-total"]),
currentPage: page,
query: inputValue
});
})
.catch(() => {
console.log("Error");
});
};
render() {
return (
<div className="app">
<SearchBar onSubmit={this.fetchPhotos} />
<Pagination
current={this.state.currentPage}
total={this.state.totalPhotos}
perPage={this.state.perPage}
query={this.state.query}
onPageChanged={query => this.fetchPhotos(this.state.query)}
/>
<List data={this.state.photos} />
</div>
);
}
}
const List = ({ data }) => {
var items = data.map(photo => <ListItem key={photo.id} photo={photo} />);
return <div className="grid">{items}</div>;
};
export default App;
searchbar.jsx
import React, { Component } from "react";
class SearchBar extends Component {
state = {
inputValue: ""
};
handleFormSubmit = e => {
e.preventDefault();
this.props.onSubmit(this.state.inputValue);
};
render() {
return (
<div className="header">
<h1>Search for images on Unsplash</h1>
<form onSubmit={this.handleFormSubmit} className="ui form">
<input
type="text"
placeholder="Type here to search for images"
value={this.state.inputValue}
onChange={e => this.setState({ inputValue: e.target.value })}
/>
</form>
</div>
);
}
}
导出默认搜索栏;
pagination.jsx
import React, { Component } from "react";
class Pagination extends Component {
pages() {
var pages = [];
for (var i = this.rangeStart(); i <= this.rangeEnd(); i++) {
pages.push(i);
}
return pages;
}
rangeStart() {
var start = this.props.current - this.props.pageRange;
return start > 0 ? start : 1;
}
rangeEnd() {
var end = this.props.current + this.props.pageRange;
var totalPages = this.totalPages();
return end < totalPages ? end : totalPages;
}
totalPages() {
return Math.ceil(this.props.total / this.props.perPage);
}
nextPage() {
return this.props.current + 1;
}
prevPage() {
return this.props.current - 1;
}
hasFirst() {
return this.rangeStart() !== 1;
}
hasLast() {
return this.rangeEnd() < this.totalPages();
}
hasPrev() {
return this.props.current > 1;
}
hasNext() {
return this.props.current < this.totalPages();
}
changePage(page) {
this.props.onPageChanged(page);
console.log("Page inside Pagination", page);
}
render() {
return (
<div className="pagination">
<div className="pagination__left">
<span
role="button"
className={!this.hasPrev() ? "hidden" : ""}
onClick={e => this.changePage(this.prevPage())}
>
Prev
</span>
</div>
<div className="pagination__mid">
<ul>
<li className={!this.hasFirst() ? "hidden" : ""}>
<span role="button" onClick={e => this.changePage(1)}>
1
</span>
</li>
<li className={!this.hasFirst() ? "hidden" : ""}>...</li>
{this.pages().map((page, index) => {
return (
<li key={index}>
<span
role="button"
onClick={e => this.changePage(page)}
className={this.props.current === page ? "current" : ""}
>
{page}
</span>
</li>
);
})}
<li className={!this.hasLast() ? "hidden" : ""}>...</li>
<li className={!this.hasLast() ? "hidden" : ""}>
<span
role="button"
onClick={e => this.changePage(this.totalPages())}
>
{this.totalPages()}
</span>
</li>
</ul>
</div>
<div className="pagination__right">
<span
className={!this.hasNext() ? "hidden" : ""}
onClick={e => this.changePage(this.nextPage())}
>
Next
</span>
</div>
</div>
);
}
}
Pagination.defaultProps = {
pageRange: 2
};
export default Pagination;
我认为您的错误在``on Change'',因为您正在提供当前状态查询以获取而不是新查询:
onPageChanged={query => this.fetchPhotos(this.state.query)}
您应该将其替换为新查询,例如:
onPageChanged={query => this.fetchPhotos(query)}
编辑1:
您可以在https://codesandbox.io/s/9ymjj8ko9p?fontsize=14。
就像我说的那样,更改是在app.jsx上:
- 参数固定的传递页面从函数参数而不是
将OnPageChange Prop固定在分页上,例如:
onPageChanged={page => this.fetchPhotos(this.state.query, page)}