Question

CODE：

var RecipeBox = React.createClass({

    getInitialState: function () {
        return {
           recipesArray: [],
           adding: false,
           editing: false,
           currentIndex: 0
        };
    },

    handleClick: function () {
        this.setState({
            adding: true
        }); 
    },
    handleEditClick: function(index) {
        this.setState({
            editing: true,
            currentIndex: index
        }); 
    },
    handleClose: function() {
        this.setState({
            adding: false,
            editing: false
        });
    },
    handleAdd: function(newRecipe) {
        this.setState({
            recipesArray: this.state.recipesArray.concat(newRecipe)
        });
        console.log(this.state.recipesArray);
    },
    handleEdit: function(newRecipe, index) {
        var newRecipesArray = this.state.recipesArray;
        newRecipesArray[index-1] = newRecipe;
        this.setState({
            recipesArray: newRecipesArray
        });

    },

    render: function() {
        var i = 0;
        var that = this;

        var recipes = this.state.recipesArray.map(function(item) {
            i++
            that.handleEditClickSingle = that.handleEditClick.bind(this, i);
            return (
                <div className="table">
                    <Recipe key={i} name={item.name} ingredients={item.ingredients} />
                    <button key ={"edit"+i} onClick={that.handleEditClickSingle} className="btn edit btn-primary">Edit</button>
                    <button  key ={"delete"+i} className="btn delete btn-danger">Delete</button>
                </div>
            );
        });

        return (
            <div>
                <h1>React.js Recipe Box</h1>
                <button className="btn btn-primary" onClick={this.handleClick}>Add Recipe</button>
                <table>
                    <tbody>
                        <tr>
                            <th>RECIPES</th>
                        </tr>
                    </tbody>
                </table>
                {recipes}
                { this.state.adding ? <AddRecipe handleClose={this.handleClose}  handleAdd={this.handleAdd} /> : null }
                { this.state.editing ? <EditRecipe currentIndex = {this.state.currentIndex} handleClose={this.handleClose}  handleEdit={this.handleEdit()}/> : null }
            </div>
        );
    },
});

状况：

错误：

在现有状态转换期间（例如render内）无法更新。渲染方法应该是道具和状态的纯函数。

我做错了什么？

问题的关键似乎在这里：

that.handleEditClickSingle = that.handleEditClick.bind（this，i）;

Answer 1

<强> SOLUTION：

var i = 0;
        var that = this;

        var recipes = this.state.recipesArray.map(function(item) {
            i++
            return (
                <div className="table">
                    <Recipe key={i} name={item.name} ingredients={item.ingredients} />
                    <button key ={"edit"+i} onClick={() => { that.handleEditClick(i)}} className="btn edit btn-primary">Edit</button>
                    <button  key ={"delete"+i} className="btn delete btn-danger">Delete</button>
                </div>
            );
        });

Answer 2

我认为您的问题在于以下行中的render方法

{ this.state.editing ? <EditRecipe currentIndex = {this.state.currentIndex} handleClose={this.handleClose}  handleEdit={this.handleEdit()}/> : null }

将其替换为

{ this.state.editing ? <EditRecipe currentIndex = {this.state.currentIndex} handleClose={this.handleClose}  handleEdit={this.handleEdit}/> : null }

您正在呼叫this.handleEdit。相反，你应该像上面那样传递它。

在现有状态转换期间无法更新（例如在`render`中）。渲染方法应该是道具和状态

2 个答案: