11-09-2011 11:53 AM
We have a customer that we have deployed a pure web application using HTML5 (running in the browser). The 'app' downloads a series of files to the device when first launching. This is done using HTML5 Application Cache Manifest. However, we have found on the OS 6 devices, that the download fails each time and then the files are downloaded EVERY subsequent time the user accesses the URL.
HOWEVER, we have found a fix/workaround but it is rather painful. Here is the fix:
1. Pull the battery on the device
2. Once its rebooted, Go to Media->Explore
3. Drop down the menu and click on Show Hidden
4. Then go to /Device/BlackBerry/System/appdata/rim
5. Delete the WebStorage folder
Now go to the URL on the Browser. Again, the pages are downloaded and this time all is well. My hypothesis is that there is some sort of corruption in the app cache DB which is causing the app cache download to fail. Once we delete the DB it is correctly re-created.
So far we have only seen this issue on a 9700 6.0 Bundle 2647 (v18.104.22.1686 Platform 22.214.171.124). I know that there is a more up to date OS so I willl definitely get the customer to upgrade and see if that solves the issue.
My question to you is:
1. Has anyone seen this before? If so, do you have an alternative fix/workaround?
2. Does anyone know if there is a way of remotely deleting the webstorage folder? That way we can not ask the user to step through this painful process.
11-10-2011 07:07 PM
I have never heard of this issue myself.
My first question is if you're seeing this independant of whether they have an SD card. Most 6.0 devices don't require them for storage, but a 9700 has very little space so I wonder if this makes a difference.
Also, are you implementing the "error" event on the cache?
Does it make a difference if you try and force an update vs just swapcache?
Lastly there is an API to delete a folder in webworks but I don't know if you have access to delete that folder dynamicallyy (sounds dangerous to allow).
11-11-2011 12:00 PM
We are now seeing this behavior on Torch 9800 v6.0.0600 Platform 126.96.36.199
So this issue seems to have happend in the more recent releases of the 6 OS. We have tested on earlier releases and its is fine.
We have managed to replicate it on our system. The manfiest download error occurs (yes we have implemented the error event) after the user opens the browser, clicks on options scrolls to the bottom, checks all the boxes and clicks on Clear Now. However, even after they clear we can see that the applicationcache.db is not 0 bytes which means that the clearing operation has failed. However, there is obviously something out of synch at that point since any subsequent attempt to update the app cache fails. The only way to correct this is to manually delete the folder as stipulated in my inital post.
While it is only an issue when the user deletes their browser cache, it still can occur on occasion and it will be difficult to walk an end-user through the process.
01-30-2012 02:20 PM
I am also seeing this, I am using the NS Basic platform for writing HTML 5 Apps on the Blackberry. No way to get rid of the black error box until I used the procedure in Post #1. This is pretty annoying and detracts from the App.
Blackberry Torch 9800
6.0 Bundle 2647 (v188.8.131.520, Platform 184.108.40.206)
Surely there must be a better way to resolve this issue?