javascript - Is React's setState asynchronous or something? -


hmm. i'm using setstate , reason code following doesn't have access new state!

what gives?!

yeap. it's asynchronous. i'm posting because isn't obvious new react users.

react "queues" updates component's state.

if need execute code block that's dependent on new state change, pass callback so:

getinitialstate: function () {   return {     isfinalcountdown: false,   } }  //blablabla  //then somewhere got... this.setstate(   {isfinalcountdown: true},   function () {//<--- whoa. solves your synchrosity woes!     console.log(this.state.isfinalcountdown); //true!   } );  console.log(this.state.isfinalcountdown); //false!

all of in docs, it's needs reiterated avoid common bugs new react users come across.

check out: https://facebook.github.io/react/docs/component-api.html#setstate


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