ReactJS：如何修改动态子组件状态或父组件道具？

Question

<RadioGroup>
    <Button title="A" />
    <Button title="B" />
</RadioGroup>

以下是radiogroup.jsx:

module.exports = React.createClass({

    onChange: function( e ) {
        // How to modify children properties here???
    },

    render: function() {
        return (<div onChange={this.onChange}>
            {this.props.children}
        </div>);
    }

});

code>button.jsx的来源并不重要，它有一个常规的HTML单选按钮，触发本机DOMonchange事件

预期流量为：

null

<RadioGroup>
    <Button title="A" />
    <Button title="B" />
</RadioGroup>

<RadioGroup>
    <OtherThing title="A" />
    <OtherThing title="B" />
</RadioGroup>

尝试：在radioGroup的onChange处理程序中：

React.Children.forEach( this.props.children, function( child ) {

    // Set the selected state of each child to be if the underlying <input>
    // value matches the child's value

    child.setState({ selected: child.props.value === e.target.value });

});

问题：

Invalid access to component property "setState" on exports at the top
level. See react-warning-descriptors . Use a static method
instead: <exports />.type.setState(...)

尝试：在radioGroup的onChange处理程序中：

React.Children.forEach( this.props.children, function( child ) {

    child.props.selected = child.props.value === e.target.value;

});

React.Children.forEach( this.props.children, function( item ) {
    this.transferPropsTo( item );
}, this);

Failed to make request: Error: Invariant Violation: exports: You can't call
transferPropsTo() on a component that you don't own, exports. This usually
means you are calling transferPropsTo() on a component passed in as props
or children.

<RadioGroup items=[
    { type: Button, title: 'A' },
    { type: Button, title: 'B' }
]; />

Answer 1

我不确定为什么您说使用clonewithprops是一个糟糕的解决方案，但这里有一个使用它的工作示例。

var Hello = React.createClass({
    render: function() {
        return <div>Hello {this.props.name}</div>;
    }
});

var App = React.createClass({
    render: function() {
        return (
            <Group ref="buttonGroup">
                <Button key={1} name="Component A"/>
                <Button key={2} name="Component B"/>
                <Button key={3} name="Component C"/>
            </Group>
        );
    }
});

var Group = React.createClass({
    getInitialState: function() {
        return {
            selectedItem: null
        };
    },

    selectItem: function(item) {
        this.setState({
            selectedItem: item
        });
    },

    render: function() {
        var selectedKey = (this.state.selectedItem && this.state.selectedItem.props.key) || null;
        var children = this.props.children.map(function(item, i) {
            var isSelected = item.props.key === selectedKey;
            return React.addons.cloneWithProps(item, {
                isSelected: isSelected,
                selectItem: this.selectItem,
                key: item.props.key
            });
        }, this);

        return (
            <div>
                <strong>Selected:</strong> {this.state.selectedItem ? this.state.selectedItem.props.name : 'None'}
                <hr/>
                {children}
            </div>
        );
    }

});

var Button = React.createClass({
    handleClick: function() {
        this.props.selectItem(this);
    },

    render: function() {
        var selected = this.props.isSelected;
        return (
            <div
                onClick={this.handleClick}
                className={selected ? "selected" : ""}
            >
                {this.props.name} ({this.props.key}) {selected ? "<---" : ""}
            </div>
        );
    }

});


React.renderComponent(<App />, document.body);

这里有一个jsFiddle显示了它的作用。

编辑：这里有一个更完整的示例，包含动态选项卡内容：jsFiddle