Sort method of my flatList

Question

 <FlatList
                style={{backgroundColor: 'white', marginTop: 10}}
                data={this.state.progr.data.sort((a, b) => a.start_time > b.start_time).filter(x => x.period === '2019-10-17T00:00:00.000-03:00')}
                renderItem={({item}) => this.renderItem({item})}
                keyExtractor = {(item, index) => item.id.toString()}
            />

The start_time being ordered gives me a JSON date, so 2019-09-10T14:00:00.000-03:00". I want to order by the hour.

I’ve tried it this way:

<FlatList
                style={{backgroundColor: 'white', marginTop: 10}}
                data={this.state.progr.data.sort((a, b) => a.(new Date(start_time).getHours()) > b.(new Date(start_time).getHours()).filter(x => x.period === '2019-10-17T00:00:00.000-03:00')}
                renderItem={({item}) => this.renderItem({item})}
                keyExtractor = {(item, index) => item.id.toString()}
            />

I tried it like this and it didn’t crt. Can someone help me with the syntax please?!

Answer 1

To sort by the time use this code similar to the one I sent you before by date:

let listaRecebida = [
	{"period": "2019-10-19T19:00:00.000-03:00"},
	{"period": "2019-10-11T11:00:00.000-03:00"},
	{"period": "2019-10-16T16:00:00.000-03:00"},
	{"period": "2019-10-13T13:00:00.000-03:00"},
	{"period": "2019-10-27T07:00:00.000-03:00"},
	{"period": "2019-10-19T19:03:00.000-03:00"},
	{"period": "2019-10-19T19:01:00.000-03:00"},
	{"period": "2019-10-19T19:02:00.000-03:00"},
];

function apenasHoras(dataStr) {
  const data = new Date(dataStr);
  const horas = data.getHours().toString().padStart(2, '0');
  const minutos = data.getMinutes().toString().padStart(2, '0');
  const segundos = data.getSeconds().toString().padStart(2, '0');
  return `${horas}${minutos}${segundos}`;
}

listaOrdenada = listaRecebida.sort(
	function(a, b){
  	const varA = apenasHoras(a.period);
  	const varB = apenasHoras(b.period);
  	return varA-varB;
  }
)

console.log('Lista ordenada');
listaOrdenada.forEach(item => {
  console.log(item.period);
});

I want to give you 2 observations/indications:

1. Sort when receiving the object and not in rendering it.

2. No filter is used to sort. Filter as the name says is to filter, that is, only items that return positive in the filter routine will be displayed.

Any doubt we’re here.