我试图使用react来创建元素的列表,并单击单个元素时更新此列表的父级的状态。更新React Grandparent状态从onClick在Grandchild
整体容器是App.jsx(祖父母)
class App extends Component {
constructor(props) {
super(props);
this.state = {
selectedClass: null,
query: "cs 2110"
}
this.handleSelectClass.bind(this);
}
handleSelectClass(classId) {
console.log(classId);
//get the id of the course and get full course details
Meteor.call('getCourseById', classId, function(error, result) {
if (!error) {
console.log(this.state);
this.setState({selectedClass: result, query: ""}, function() {
console.log(this.state.selectedClass);
console.log(this.state.query);
});
} else {
console.log(error)
}
});
}
//check if a class is selected, and show a coursecard only when one is.
renderCourseCard() {
var toShow = <div />; //empty div
if (this.state.selectedClass != null) {
toShow = <CourseCard course={this.state.selectedClass}/>;
}
return toShow;
}
render() {
return (
<div className="container">
<header>
<h1>Todo List</h1>
</header>
<div className='row'>
<input />
<Results query={this.state.query} clickFunc={this.handleSelectClass}/>
</div>
<div className='row'>
<div className="col-md-6">
{this.renderCourseCard()}
</div>
<div className="col-md-6 panel-container fix-contain">
<Form courseId="jglf" />
</div>
</div>
</div>
);
}
}
的父容器是Results.jsx
export class Results extends Component {
constructor(props) {
super(props);
}
renderCourses() {
if (this.props.query != "") {
return this.props.allCourses.map((course) => (
//create a new class "button" that will set the selected class to this class when it is clicked.
<Course key={course._id} info={course} handler={this.props.clickFunc}/>
));
} else {
return <div />;
}
}
render() {
return (
<ul>
{this.renderCourses()}
</ul>
);
}
}
与课程列表项是孙子部件
export default class Course extends Component {
render() {
var classId = this.props.info._id;
return (
<li id={classId} onClick={() => this.props.handler(classId)}>{this.props.info.classFull}</li>
);
}
}
我按照这里的建议Reactjs - How to pass values from child component to grand-parent component?传递回调函数n,但回调仍然不能识别祖父母的状态。 console.log(this.state)在App.jsx中返回undefined,即使classId是正确的,并且错误显示为“Exception in delivery result invocation'getCourseById':TypeError:this.setState不是函数”
这是绑定的问题吗?我已经尝试过没有课程作为自己的组件,并有相同的问题。
我试过这些改变,但我仍然在日志中得到一个未定义的this.state(虽然没有错误,流星调试打印“无信息”)。我使用的是最新的Meteor版本,所以我相信它正在运行es6 - 我看到安装了es5-shim和[email protected]软件包。 –
刚刚看到你绑定你的函数到组件不正确,它是'this.handleSelectClass = this.handleSelectClass.bind(this);' – Win
啊我错过了 - 非常感谢你,修复它! –