BasicWizardv2.es6

class BasicWizard extends React.Component {
  /*
  snip...
  */
 _next(data) {
   // data is the user input from the form
   // it could be saved here in state or POSTed to an API, for example
   // after that is done, we'll move currentStep forward
   
   // look familiar?
   let currentStep = this.state.currentStep;
   if (currentStep >= 2) {
     currentStep = 3;
   } else {
     currentStep = currentStep + 1;
   }
   
   this.setState({
     currentStep: currentStep
   });
 }
 render() {
   let currentStep - this.state.currentStep;
   return(
     <div>
        <Step1 currentStep={currentStep) afterValid={this._next} />
        <Step2 currentStep={currentStep) afterValid={this._next} />
        <Step3 currentStep={currentStep) afterValid={this._next} />
     </div>
   );
 }
}