koobas.hobune.stream
Trouble Getting External Data Using WWW
Trying to use WWW to pull data from my webservice and I originally got an error saying "WWW is not ready downloading yet".
So, I figure I have to use "yield return www;", which led to me to using a delegate method. Now I am getting error: "NullReferenceException UnityEngine.MonoBehaviour.StartCoroutine (IEnumerator routine)".
I'm an experience .net C# developer, but this is seriously giving me trouble. What is the best way to go about something like this? Thanks!
In my ItemCatelog class:
private void RequestItemCatelog()
{
data.GetItemCatelog(RecieveItemCatelog);
}
private void RecieveItemCatelog(CatelogItem[] items)
{
Debug.Log(items[0].ItemName);
}
and in my datahelper class:
public delegate void GetItemCatelogReceiver(CatelogItem[] items);
public void GetItemCatelog(GetItemCatelogReceiver _GetItemCatelogReceiver)
{
StartCoroutine(GetItemCatelogResponse(_GetItemCatelogReceiver));
}
IEnumerator GetItemCatelogResponse(GetItemCatelogReceiver _GetItemCatelogReceiver)
{
WWW www = new WWW(url);
Debug.Log(www.text);
yield return www;
CatelogItem[] items = JsonMapper.ToObject<CatelogItem[]>(www.text);
Debug.Log(www.text);
_GetItemCatelogReceiver(items);
}
I had a problem when i copied your script because of requesting www.text before yielding to www. Here is the test I did with success and excluding the json list.
using UnityEngine;
using System.Collections;
public class WWWTest : MonoBehaviour
{
public delegate void GetItemCatelogReceiver(string text);
void Start()
{
GetItemCatelog(RecieveItemCatelog);
}
void GetItemCatelog(GetItemCatelogReceiver _GetItemCatelogReceiver)
{
StartCoroutine("GetItemCatelogResponse", _GetItemCatelogReceiver);
}
IEnumerator GetItemCatelogResponse(GetItemCatelogReceiver _GetItemCatelogReceiver)
{
WWW www = new WWW("http://www.google.com");
yield return www;
_GetItemCatelogReceiver(www.text);
}
private void RecieveItemCatelog(string text)
{
Debug.Log(text);
}
}
Unity crashes everytime it reaches "yield return www". Unity 5.3.4
I got it working!
void Awake()
{
isFirstRound = true;
WWW result = GET("http://dev.wisc-online.com/Prototypes/muscle_structure.json");
}
public WWW GET(string url)
{
WWW www = new WWW(url);
StartCoroutine(WaitForWWW(www));
//do nothing untill json is loaded
while (!www.isDone) { }
if (www.error == null || www.error == "")
{
gameData = convertFromJSONToMyClass(www.text);
Debug.Log("gameData = " + gameData);
}
else
{
Debug.Log("WWW error: " + www.error);
}
return www;
}
IEnumerator WaitForWWW(WWW www)
{
yield return www;
}
The problem was my ItemCatelog class was instantiating the DataHelper class with new(). Old .net habits die hard.
"yield return www" I had put in place to reproduce the "WWW is not ready downloading yet" error and accidently made it into the snippet.
In my case, my game must wait for the web results before continuing, there is nothing to do while the results arrive, so I programmed it to wait until WWW is ready downloading.
using UnityEngine;
using System.Collections;
public class Principal : MonoBehaviour
{
// This could be one of many methods which require data from web.
public void Browse ()
{
// Make a call to the "GET" method providing the url.
WWW result = GET("https://www.google.com.mx/search?q=UnityException%3A+WWW+is+not+ready+downloading+yet&oq=UnityException%3A+WWW+is+not+ready+downloading+yet&aqs=chrome..69i57j69i58.349j0j9&sourceid=chrome&es_sm=93&ie=UTF-8#safe=off&q=UnityException:+WWW+is+not+ready+downloading+yet");
// Show the output.
Debug.Log(result.text);
}
// The "GET" method is apart because it could be called from many methods.
public WWW GET (string url)
{
// Create the WWW object and provide the url of this web request.
WWW www = new WWW (url);
// Run the web call in the background.
StartCoroutine (WaitForRequest (www));
// Do nothing until the response is complete.
while (!www.isDone) {}
// Deliver the result to the method that called this one.
return www;
}
// Run the web call and deliver the result as it is arriving.
private IEnumerator WaitForRequest (WWW www)
{
yield return www;
}
}
