Recurrence function in React Native -

i add recurrence function in react native project, settimeout doesn't work. can tell me why? , how fix it?

handleappstatechange(appstate) {     if(appstate === 'background') {         let = 0;         function runaction() {             i++;             console.log('result'+i);             settimeout("runaction()",1000);         }         runaction();     } }  

first argument of settimeout function, try to

settimeout(runaction,1000);