context.jsx

class Tab {
 static childContextTypes = {
   registerHook: PropTypes.func
 }
 
 constructor() {
   super()
   this._hooks = []
 }
 
 getChildContext() {
   return {
     registerHook: fn => this._hooks.push(fn)
   }
 }
 
 onClose() {
   if (this._hooks.some(fn => fn()))
     return
   // close logic  
 }
 
 render() {
   //...
 }
}

class SomeChild {
  static contextTypes = {
   registerHook: PropTypes.func
 }
 
 constructor() {
   super()
   this._hooks = []
 }
 
 componentWillMount(){
    this.context.registerHook(() => {
      return this.isDirty
    })
 }
}