how to execute a function after end another in react native? - react-native

Question

I have a query that I have a function which response to a server, so it takes a while and when it tries to execute the other function, an error occurs. Since the function responds an array from which comes from the server and when the other function requests that, even It does not have. Have to solve this. example :
responseServer(tarea) {
return fetch(url)
.then((response) => response.json())
.then((responseJson) => {
this.setState({ refresh: false })
global.refresh = false
let data = [];
let Milestone = [];
Object.values(responseJson.summary).forEach(item => {
data = data.concat(item);
});
const result = ["Milestone"]
.reduce((total, category) => ({
...total,
[category]: data.filter(line => line.includes(category))
}), {})
Object.values(result.Milestone).forEach(item => {
Milestone = Milestone.concat(item)
});
this.setState({
Milestone: Milestone
})
})
}
and another function
sacarPorcentaje(item) {
this.responseServer(item)
let summaryCopy = this.state.Milestone.map(data => {return data.split(",")})
console.log(summaryCopy)
var Okeys = 0;
var total = 0;
for (var i = 0; i < summaryCopy.length; i++){
for(var j = 0; j < summaryCopy[i].length; j++){
if(summaryCopy[i][j] === "OK") {
Okeys = Okeys + 1
}
}
total = total + 1
}
console.log(Okeys)
console.log(total)
}

Answer 1

You should update sacarPorcentaje() to async function. then await the function call, will resolve your issue
async sacarPorcentaje (item) {
await this.responseServer(item)
let summaryCopy = this.state.Milestone.map(data => {return data.split(",")})
console.log(summaryCopy)
var Okeys = 0;
var total = 0;
for (var i = 0; i < summaryCopy.length; i++){
for(var j = 0; j < summaryCopy[i].length; j++){
if(summaryCopy[i][j] === "OK") {
Okeys = Okeys + 1
}
}
total = total + 1
}
console.log(Okeys)
console.log(total)
}
There is also one more solution for this issue. please search how to use Promise in JS

Answer 2

I think you need to use then when you call responseServer function in sacarPorcentaje function.
sacarPorcentaje(item) {
this.responseServer(item).then(() => {
let summaryCopy = this.state.Milestone.map(data => {return data.split(",")})
console.log(summaryCopy)
var Okeys = 0;
var total = 0;
for (var i = 0; i < summaryCopy.length; i++){
for(var j = 0; j < summaryCopy[i].length; j++){
if(summaryCopy[i][j] === "OK") {
Okeys = Okeys + 1
}
}
total = total + 1
}
console.log(Okeys)
console.log(total)
}
}