Ik probeer een AsyncTask aan te roepen via een methode van ParseQuerys Class om die informatie te gebruiken in een ListView van mijn Fragment lvRestaurantFrag. Het probleem is dat de methode null retourneert omdat de AsyncTask niet aankomt bij de onPostExecute. Ik weet niet hoe ik het kan repareren.
Hier laat ik mijn code achter:
JSON
API-koppeling
"idBranchRestaurant": 1,
"idRestaurant": 1,
"restaurant":{
"idRestaurant": 1,
"name": "Don Julio",
"description": "La mejor parrilla para cualquier turista",
"sociaal netwerk":[
"idSocialNetworkRestaurant": 1,
"idRestaurant": 1,
"idTypeSocialNetwork": 1,
"value": "www.donjulio.com.ar",
"type":{
"idTypeSocialNetwork": 1,
"name": "Website",
"icon": "website_ic.jpg"
"idRangePriceBranch": 1,
"RangePrice": {
"idRangePriceBranch": 1,
"idBranchRestaurant": 1,
"minimum": 300,
"maximum": 600
"name": "Paraguay",
"foto":[
"idBranchPhoto": 4,
"idBranchRestaurant": 1,
"branch": null,
"idUser": 0,
"gebruiker": null,
"photo": "entradaDonJulio.jpg"
"keuken":[
"idCousine": 1,
"name": "Parrilla"
"menu":[
"idTypeMenu": 1,
"name": "Mediodia",
"idBranchRestaurant": 1,
"platen": null
"idTypeMenu": 2,
"name": "Noche",
"idBranchRestaurant": 1,
"platen": null
"filter":[
"idTypeFilter": 2,
"name": "Familie",
"icon": "family_ic.jpg"
"onderhoud":[
"idService": 2,
"name": "Comida para celiacos"
"idService": 1,
"name": "Wifi"
"rooster":[
"idTimetableBranch": 11,
"idBranchRestaurant": 1,
"idDay": 2,
"openingHour": "19 uur",
"closingHour": "24 uur",
"dag":{
"idDay": 2,
"name": "Tuesday"
"idTimetableBranch": 10,
"idBranchRestaurant": 1,
"idDay": 2,
"openingHour": "12 uur",
"closingHour": "16 uur",
"dag":{
"idDay": 2,
"name": "Tuesday"
"idTimetableBranch": 9,
"idBranchRestaurant": 1,
"idDay": 1,
"openingHour": "19 uur",
"closingHour": "24 uur",
"dag":{
"idDay": 1,
"name": "Maandag"
"idTimetableBranch": 8,
"idBranchRestaurant": 1,
"idDay": 1,
"openingHour": "12 uur",
"closingHour": "16 uur",
"dag":{
"idDay": 1,
"name": "Maandag"
"idTimetableBranch": 12,
"idBranchRestaurant": 1,
"idDay": 3,
"openingHour": "12 uur",
"closingHour": "16 uur",
"dag":{
"idDay": 3,
"name": "woensdag"
"idTimetableBranch": 13,
"idBranchRestaurant": 1,
"idDay": 3,
"openingHour": "19 uur",
"closingHour": "24 uur",
"dag":{
"idDay": 3,
"name": "woensdag"
"idTimetableBranch": 14,
"idBranchRestaurant": 1,
"idDay": 4,
"openingHour": "12 uur",
"closingHour": "16 uur",
"dag":{
"idDay": 4,
"name": "Donderdag"
"idTimetableBranch": 15,
"idBranchRestaurant": 1,
"idDay": 4,
"openingHour": "19 uur",
"closingHour": "24 uur",
"dag":{
"idDay": 4,
"name": "Donderdag"
"idTimetableBranch": 16,
"idBranchRestaurant": 1,
"idDay": 5,
"openingHour": "12 uur",
"closingHour": "16 uur",
"dag":{
"idDay": 5,
"name": "Friday"
"idTimetableBranch": 17,
"idBranchRestaurant": 1,
"idDay": 5,
"openingHour": "19 uur",
"closingHour": "2 uur",
"dag":{
"idDay": 5,
"name": "Friday"
"latitude": "87654322",
"longitude": "23456789",
"calification": null,
"gemiddeld eten": 4,0,
"gemiddelde service": 4,0,
"gemiddelde sfeer": 4,0,
"averageCalification": 4,0,
"Promotie":[
"idPromotion": 3,
"idTypePromotion": 2,
"code": "DIADELPADRE",
"name": "Dia Del Padre Regalo",
"startDate": "2017-06-26T00: 00: 00",
"expireDate": "2017-06-18T00: 00: 00",
"description": "postre de regalo",
"waarde": 100,
"type":{
"idTypePromotion": 2,
"name": "Cadeau"
"idBranchRestaurant": 2,
"idRestaurant": 2,
"restaurant":{
"idRestaurant": 2,
"name": "La Hormiga",
"description": "el lugar explota de gente y en especial de gente de ort",
"sociaal netwerk":[
"idSocialNetworkRestaurant": 2,
"idRestaurant": 2,
"idTypeSocialNetwork": 2,
"value": "www.facebook.com/LaHormiga",
"type":{
"idTypeSocialNetwork": 2,
"name": "Facebook",
"icon": "fb_ic.jpg"
"idRangePriceBranch": 1,
"RangePrice": {
"idRangePriceBranch": 1,
"idBranchRestaurant": 1,
"minimum": 300,
"maximum": 600
"name": "Ort",
"foto":[
"idBranchPhoto": 5,
"idBranchRestaurant": 2,
"branch": null,
"idUser": 0,
"gebruiker": null,
"photo": "entradaLaHormiga.jpg"
"keuken":[
"idCousine": 2,
"name": "Pizza"
"menu":[
"idTypeMenu": 3,
"name": "Mediodia",
"idBranchRestaurant": 2,
"platen": null
"filter":[
"idTypeFilter": 1,
"name": "Met korting",
"icon": "discount_ic.jpg"
"onderhoud":[
"idService": 3,
"name": "Aire acondicionado"
"idService": 1,
"name": "Wifi"
"rooster":[
"idTimetableBranch": 18,
"idBranchRestaurant": 2,
"idDay": 6,
"openingHour": "11 uur",
"closingHour": "15 uur",
"dag":{
"idDay": 6,
"name": "Zaterdag"
"idTimetableBranch": 19,
"idBranchRestaurant": 2,
"idDay": 7,
"openingHour": "11 uur",
"closingHour": "15 uur",
"dag":{
"idDay": 7,
"name": "Sunday"
"latitude": "234567897",
"longitude": "123456789",
"calification": null,
"averageFood": 5,0,
"gemiddelde service": 5,0,
"gemiddelde sfeer": 5,0,
"averageCalification": 5,0,
"Promotie":[
"idBranchRestaurant": 3,
"idRestaurant": 3,
"restaurant":{
"idRestaurant": 3,
"name": "paja rota",
"description": "La mejor parrilla de ramosmejia ",
"sociaal netwerk":[
"idSocialNetworkRestaurant": 3,
"idRestaurant": 3,
"idTypeSocialNetwork": 3,
"waarde": "twitter.com/Pajarota",
"type":{
"idTypeSocialNetwork": 3,
"name": "Twitter",
"icon": "ic_twitter.png"
"idRangePriceBranch": 3,
"RangePrice": {
"idRangePriceBranch": 3,
"idBranchRestaurant": 3,
"minimum": 50,
"maximum": 250
"name": "Ramos MEjia",
"foto":[
"idBranchPhoto": 6,
"idBranchRestaurant": 3,
"branch": null,
"idUser": 0,
"gebruiker": null,
"photo": "EntradaPajaRota.jpg"
"keuken":[
"idCousine": 1,
"name": "Parrilla"
"menu":[
"idTypeMenu": 4,
"name": "Mediodia",
"idBranchRestaurant": 3,
"platen": null
"idTypeMenu": 5,
"name": "Noche",
"idBranchRestaurant": 3,
"platen": null
"filter":[
"idTypeFilter": 2,
"name": "Familie",
"icon": "family_ic.jpg"
"onderhoud":[
"idService": 1,
"name": "Wifi"
"idService": 4,
"name": "Carta de braille"
"rooster":[
"idTimetableBranch": 20,
"idBranchRestaurant": 3,
"idDay": 5,
"openingHour": "12 uur",
"closingHour": "16 uur",
"dag":{
"idDay": 5,
"name": "Friday"
"idTimetableBranch": 21,
"idBranchRestaurant": 3,
"idDay": 5,
"openingHour": "19 uur",
"closingHour": "2 uur",
"dag":{
"idDay": 5,
"name": "Friday"
"idTimetableBranch": 22,
"idBranchRestaurant": 3,
"idDay": 6,
"openingHour": "12 uur",
"closingHour": "16 uur",
"dag":{
"idDay": 6,
"name": "Zaterdag"
"idTimetableBranch": 23,
"idBranchRestaurant": 3,
"idDay": 6,
"openingHour": "19 uur",
"closingHour": "2 uur",
"dag":{
"idDay": 6,
"name": "Zaterdag"
"idTimetableBranch": 24,
"idBranchRestaurant": 3,
"idDay": 7,
"openingHour": "12 uur",
"closingHour": "16 uur",
"dag":{
"idDay": 7,
"name": "Sunday"
"latitude": "12345678",
"longitude": "87654321",
"calification": null,
"averageFood": 5,0,
"gemiddelde service": 5,0,
"gemiddelde sfeer": 5,0,
"averageCalification": 5,0,
"Promotie":[
"idBranchRestaurant": 4,
"idRestaurant": 4,
"restaurant":{
"idRestaurant": 4,
"name": "la espiga",
"description": "el mejor lugar para comer pastas",
"sociaal netwerk":[
"idSocialNetworkRestaurant": 4,
"idRestaurant": 4,
"idTypeSocialNetwork": 4,
"value": "instagram.com/laespiga",
"type":{
"idTypeSocialNetwork": 4,
"name": "Instagram",
"icon": "ic_Instagram.png"
"idRangePriceBranch": 4,
"RangePrice": {
"idRangePriceBranch": 4,
"idBranchRestaurant": 4,
"minimum": 80,
"maximum": 150
"name": "Almagro",
"foto":[
"idBranchPhoto": 7,
"idBranchRestaurant": 4,
"branch": null,
"idUser": 0,
"gebruiker": null,
"photo": "EntradaLaEspiga.jpg"
"keuken":[
"idCousine": 4,
"name": "Pasta"
"menu":[
"idTypeMenu": 6,
"name": "Tarde",
"idBranchRestaurant": 4,
"platen": null
"filter":[
"idTypeFilter": 1,
"name": "Met korting",
"icon": "discount_ic.jpg"
"onderhoud":[
"idService": 1,
"name": "Wifi"
"idService": 3,
"name": "Aire acondicionado"
"rooster":[
"idTimetableBranch": 26,
"idBranchRestaurant": 4,
"idDay": 1,
"openingHour": "16 uur",
"closingHour": "19 uur",
"dag":{
"idDay": 1,
"name": "Maandag"
"idTimetableBranch": 27,
"idBranchRestaurant": 4,
"idDay": 2,
"openingHour": "16 uur",
"closingHour": "19 uur",
"dag":{
"idDay": 2,
"name": "Tuesday"
"idTimetableBranch": 28,
"idBranchRestaurant": 4,
"idDay": 3,
"openingHour": "16 uur",
"closingHour": "19 uur",
"dag":{
"idDay": 3,
"name": "woensdag"
"idTimetableBranch": 29,
"idBranchRestaurant": 4,
"idDay": 4,
"openingHour": "16 uur",
"closingHour": "19 uur",
"dag":{
"idDay": 4,
"name": "Donderdag"
"idTimetableBranch": 30,
"idBranchRestaurant": 4,
"idDay": 5,
"openingHour": "16 uur",
"closingHour": "19 uur",
"dag":{
"idDay": 5,
"name": "Friday"
"latitude": "87657467",
"longitude": "45254567",
"calification": null,
"averageFood": 5,0,
"gemiddelde service": 5,0,
"gemiddelde sfeer": 5,0,
"averageCalification": 5,0,
"Promotie":[
ParseQuery-klasse
private String server = "http://appmorfando.azurewebsites.net/api/";
ParsingObjects parse = nieuwe ParsingObjects ();
// Query voor lijstvertakkingen
private ArrayList branches = nieuwe ArrayList ();
openbare ArrayList getAllBranch (int limit, int offset) {
nieuwe BranchGetAll (). execute ("branch /", limit + "", offset + "");
retourneer takken;
private class BranchGetAll breidt AsyncTask uit > {
protected void onPostExecute (ArrayList datos) {
super.onPostExecute (datos);
branches = datos;
@Override
beschermde ArrayList doInBackground (String ... parametros) {
String url = parametros [0] + parametros [1] + "/" + parametros [2];
ArrayList branchList = nieuwe ArrayList ();
OkHttpClient client = nieuwe OkHttpClient ();
Request request = nieuwe Request.Builder ()
.url (server + url)
.bouwen();
String resultado;
proberen {
Antwoordantwoord = client.newCall (verzoek) .execute (); // Llamo al API Rest servicio1 en ejemplo.com
resultado = response.body (). string ();
} catch (IOException e) {
Log.d ("Fout", e.getMessage ()); // Fout in het netwerk
null teruggeven;
proberen{
JSONArray jsonBranch = nieuwe JSONArray (resultado);
voor (int i = 0; i listBranches;
openbare weergave onCreateView (LayoutInflater-inflater, ViewGroup-groep, Bundelgegevens) {
Bekijk toReturn;
toReturn = inflater.inflate (R.layout.frag_restaurant_lv, groep, false);
main = (MainActivity) getActivity ();
pq = nieuwe ParseQuery ();
restaurantItems = (ListView) toReturn.findViewById (R.id.lvRestaurantItems);
// Hier wordt null, dus de adaptergrootte is 0
listBranches = pq.getAllBranch (10,0);
adapter = nieuwe lvRestaurantAdapter (listBranches, main);
restaurantItems.setAdapter (adapter);
restaurantItems.setOnItemClickListener (dit);
terug naarReturn;
@Override
public void onItemClick (AdapterView ouder, View view, int position, long id) {
int idBranch = adapter.getId (positie);
main.BranchSelected (idBranch);
2021-02-24 08:21:01
2 dingen hier:
Hoe weet u of uw asynctaak niet aankomt op onpostexecute? Uw bijgevoegde code overschrijft onpostexecute niet. Laten we proberen die methode te implementeren en een eenvoudige logcat of system.out uitvoeren om te bevestigen.
Uw asynctaak haalt Json-objecten van de server op en verpakt ze in een lijst die moet worden geretourneerd. Er zijn tal van manieren waarop dit kan mislukken, zoals een slechte serververbinding of een onjuiste parsering van json. Ik zou uw verbinding en gegevensstructuur zorgvuldig testen om er zeker van te zijn dat de nul iets is dat de asynctask veroorzaakt.
Een van de eenvoudigste manieren om te testen, is door al die verbinding en json-gerelateerde code te becommentariëren en vervolgens een handmatig ingevulde lijst te retourneren waarvan u weet dat deze werkt. Dit zal helpen het gebied te isoleren dat faalt.
1
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