How to "delay" the return of a function when its return value depends on an event ?

jalmince

My function here below uses UrlLoader, but returns before the Event.complete strikes....

function GetHighScores()   local url = "<a href="http://www.jalmince-lab.com/BallTrip/high_scores.php&quot" rel="nofollow">http://www.jalmince-lab.com/BallTrip/high_scores.php&quot</a>; local headers = { ["Content-Type"] = "application/x-www-form-urlencoded"}   local result = ""   local function onComplete(event) result = event.data end local loader = UrlLoader.new(url, UrlLoader.POST ) loader:addEventListener(Event.COMPLETE, onComplete)   --- Need a "delay" here !! return(result) end

Tried with a dummy loop " while not finished do end" before the return, setting finished=true in the event handler. But that freezes the player.

thanks for your help !
Jp

vitalitymobile

Hi @jalmince,
You should call drawGUI function inside onComplete function

local function onComplete(event) result = event.data drawGUI(result)     end

And then in code, you only need to call : GetHighScores()

jalmince

thanks Vitalitymobile, but It doesn' t work.

vitalitymobile

Hi @jalmince, maybe you can refer to Weather example (in Gideros setup folder ) to find out more...
onComplete is callback function, so when url load done, it's return result, and then you can pass it to other method to execute next ( that why you don't have to return in GetHighScores function)

jalmince

thanks Vitality, but that is not the answer to my issue.
The weather example processes the xml result INSIDE the onComplete function.
Imagine now that you want to create a function, say "get_weather()", that returns the xml from yahoo, and that you want to call that fonction from another function; for example:

... xml = get_weather() "process" xml ....

How do you write the function to return the xml ONLY when the event has been processed ? yor function will look like that :

function get_weather() .... local xml ... local function onComplete(event) xml = XmlParser:ParseXmlText(event.data) end ... local loader = UrlLoader.new("<a href="http://xml.weather.yahoo.com/forecastrss/USCA0987.xml&quot" rel="nofollow">http://xml.weather.yahoo.com/forecastrss/USCA0987.xml&quot</a><img class="emoji" src="http://forum.giderosmobile.com/resources/emoji/wink.png" title=";)" alt=";)" height="20" /> loader:addEventListener(Event.COMPLETE, onComplete) ... return xml

and the bottom return is always reached before the event is processed, returning nil.

vitalitymobile

I think loader and onComplete is async callback. If you really want get result when the event has been processed, you can show a loading dialog in the end of get_weather function and then in onComplete function, dispose dialog and process result?

Something like this will work

local function get_weather()   ---- detail end   local function process(xml)   ---detail   end   local xml = get_weather(); process(xml)   --->> change to async callback style   local function process(xml)   ---detail   end   local function get_weather()   ---- detail local function onComplete(event) local xml = event.result; process(xml) end end   --- main entry get_weather(); --- no need return here, when urlloader query data done, it is automatic call process