Hi everyone,
So I have an interesting problem that’s driving me nuts. I’m trying to download an image file from an online folder from my own site and when I run through the download process the event listener is called multiple times AFTER the event.isError already took place. I’ve purposely deleted the file it’s trying to download in order to test the network error chunk of this code.
I really don’t want the network event listener (eventDownloadListener) to be called that many times after the download isError was set to true so could anyone help on this?
What my code does is it checks the contents of a table to see if the names of the files needed coordinates to the files on the phone; if there is no file on the phone then the network.download() call is envoked and the app waits until the file is downloaded until it tries downloading the next one. Only 1 download is requested from the table so what is happening is it’s trying to download the non existent file then it re-tries one more time and then after that it is supposed to stop. That is when the network event listener is being called 5 more times.
Here is the code.
[lua]function eventDownloadListener(event)
if (event.isError or event.status == 404) then – If there is any kind of error in the download process
print("There has been an error downloading event image "…eventName)
numEventImgError = numEventImgError + 1
nextEventImageHandler()
elseif phase == “began” then
print("Starting to download event "…eventName)
elseif phase == “ended” then – When the download has occured successfully
print(“Event “…eventName…” has downloaded”)
nextEventImageHandler()
end
end[/lua]
This function re-directs what happens after the download based off of how many downloads are left
NOTE: the [lua]numEventImgToDownload[/lua] variable is calculated in another function that is exactly the same as the [lua]downloadEventImages()[/lua] function only without the network call. It is set to 1 in this case along with the [lua]numDownloadAttempts[/lua]
[lua]function nextEventImageHandler()
numEventImgToDownload = numEventImgToDownload - 1
print("# event images left to download = "…numEventImgToDownload)
print("# of errors = "…numEventImgError)
print("# of download attempts left = "…numDownloadAttempts)
if numEventImgToDownload > 0 then
downloadEventImages() – Download the next image
elseif numEventImgToDownload == 0 and numEventImgError == 0 then
downloadingEventImages = false
numDownloadAttempts = resetAttempts
elseif numEventImgToDownload == 0 and numEventImgError > 0 and numDownloadAttempts > 0 then – Try downloading failed files again
numDownloadAttempts = numDownloadAttempts - 1
downloadingEventImages = true
numEventImgError = 0
getNumberOfEventDownloads() – Start the whole downloading process over
elseif numEventImgToDownload == 0 and numEventImgError > 0 and numDownloadAttempts == 0 then
print(“Failed to download all files: Terminating attempts”)
downloadingEventImages = false
numDownloadAttempts = resetAttempts
eventName = “noImage”
end
end[/lua]
This function moves through the eventTable and checks to see if a file is needed to be downloaded.
[lua]function downloadEventImages()
for i = 1, #extVar.eventTable do
local path = system.pathForFile(“events/”…extVar.eventTable[i].name…extVar.prefix…".png", system.DocumentsDirectory)
local localPath = system.pathForFile(“images/”…extVar.eventTable[i].name…extVar.prefix…".png", system.ResourceDirectory)
local test = nil
local localTest = nil
if path then test = io.open(path) end
if localPath then localTest = io.open(localPath) end
if test then – If the path exists then don’t try downloading the image
test:close()
if localTest then localTest:close() end
print(“File “…extVar.eventTable[i].name…” exists in the Documents Directory”)
elseif localTest then
localTest:close()
if test then test:close() end
print(“File “…extVar.eventTable[i].name…” exists in the Resource Directory”)
else – if either path doesn’t exist then download the file
print(extVar.eventTable[i].name…" will be downloaded")
eventName = extVar.eventTable[i].name
local nameOfFile = extVar.eventTable[i].name…extVar.prefix…".png"
local URLPath = “http://myURLpath/eventPictures/"..extVar.eventTable[i].name..extVar.prefix..".png”
![http://myURLpath/eventPictures/"..extVar.eventTable[i].name..extVar.prefix..".png](http://myURLpath/eventPictures/%22..extVar.eventTable%5Bi%5D.name..extVar.prefix..%22.png){kind=link}
local directory = system.DocumentsDirectory
print("fileName = "…nameOfFile)
print("fileURL = "…URLPath)
network.download(URLPath, “GET”, eventDownloadListener, {progress = true, timeout = 5}, nameOfFile, directory)
break – Wait for the file to download and then download the next file if there is one
end
end
end[/lua]