Child to parent communication in React (JSX) without flux

Question

I\'m really new to React, and I\'m pulling my hair out trying to solve what seems to me to be a simple problem. Here\'s a picture of the component I\'ve built.

Color

Answer 1

The callback function should work. As you've mentioned in your previous comment you can use your captured this to access the updateColor function from the child:

var passTarget = this;
...
...
return <ColorButton 
  buttonColor={object} 
  key={i} 
  update={passTarget.updateColor} />

Or as Bogdan mentioned you can pass it through map after your callback function:

{colorsArray.map(function(object, i){
  return <ColorButton 
           buttonColor={object} 
           key={i} 
           update={this.updateColor} />;
}, this)}

Your <ColorButton /> component should then be able to run a simple onClick function:

onClick={this.props.update}

And then you can simply make use of normal event targets in the parent component to capture the color of the button that was clicked:

updateColor: function(e) {
  console.log(e.target.style.backgroundColor);
}

Here is a full DEMO to demonstrate.

Answer 2

You can just pass callback function into child from your parent component, as simple as this:

 <ColorButton buttonColor={object} key={i} onColorSelect={this.updateColor}/>

(when using React.createClass all class methods are already bound to this, so you are not required to call .bind(this)).

Then from ColorButton component you can call this callback as this.props.onColorSelect(...).

JS Bin example: http://jsbin.com/fivesorume/edit?js,output

Answer 3

OK, this is pretty simple in React without using flux or redux, similar to passing down props from parent to child, here we can use callback function like this:

var colorsArray = ["#ED5851", "#9CCC64", "#337AEC", "#ff7a45", "#7E58C2", "#FFEB3B", "#78909C", "#FFFFFF", "#213a4b"];


var EditDrawer = React.createClass({
    updateColor: function(i) {
        alert("New Color: " + i);
    },
    render: function(){
        return (
            <div className="container-fluid animated fadeIn extra-fast-animation tag-edit-drawer">
                <div className="row">
                    <div className="col-xs-12">
                        {colorsArray.map(function(object, i){
                            return <ColorButton buttonColor={object} key={i} updateColor={this.updateColor}/>;
                        }, this)}
                    </div>
                </div>
            </div>
        );
    }
});


var ColorButton = React.createClass({
    updateColor: function() {
        this.props.updateColor(this.props.buttonColor);
    },
    render: function(){
        var buttonStyle = {
            backgroundColor: this.props.buttonColor,
        };
        return (
            <div className="tag-edit-color-button" 
            style={buttonStyle}
            onClick={this.updateColor}>
              this.props.buttonColor
            </div>
        )
    }
});