Question

We’re writing a native iOS app which integrates with Facebook. Several months ago we set up a placeholder FB app via developers.facebook.com and have been doing all of our testing via that. Now that we’re closer to release I thought I’d set up a new, clean, “proper” FB app, with all of the correct app descriptions/URL fields/etc.

As a first step, I’ve set up the new app to be as similar to the old one as possible and made a new test user. The old app works fine, so I’m reasonably confident that our iOS code is correct (and yes I’ve switched the app ID in the XCode project and so forth), but when we run with the new app integrated we get this behaviour when trying to authorise the app with the user:

If the iOS Facebook app is installed and the test user is already logged in:

1. On calling openActiveSessionWithReadPermissions (requesting @”email” permissions), the iOS Facebook app is launched and shows the user the basic info authorisation page for our app.
2. The user clicks the “Log in” button at the top of the page.
3. The FB app pops up another, blank window with a “Cancel” button at the top left.
4. From this point on, nothing the user does will make Facebook return control to our iOS app.
5. But checking the test user’s page afterwards shows that the app has been authorised.

If I uninstall the Facebook app from the device, thereby forcing the request screens to be shown in Safari instead, we get the same behaviour except point (3) above is replaced with:

3) A device alert saying “Safari cannot open the page because the address is invalid”. This is the address it’s trying to open: https://m.facebook.com/dialog/permissions.request?_path=permissions.request&app_id=<*our_app_id*>&redirect_uri=fb<*our_app_id*>%3A%2F%2Fauthorize&sdk=ios&display=touch&type=user_agent&perms=email&fbconnect=1&sso=iphone-safari&from_login=1&client_id=<*our_app_id*>&refid=9

I’ve found this behaviour to be the same on iOS 5.1 and 6.0 hardware devices and the 6.0 simulator. Using out old FB app, the authorisation returns correctly. I’m sure that in the app admin page I just haven’t set one of the magical, barely-documented option checkboxes correctly, but I really don’t know how to go about finding out what’s going wrong.

Thanks for any advice!

Answer 1

As it’s not returning to your app, you may have forgot to add the URL scheme to your Info.plist. You should have a new entry, here’s the XML representation of it:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
    <plist version="1.0">
        <array>
        <dict>
                <key>CFBundleURLSchemes</key>
                <array>
                    <string>fbYOUR_APP_ID</string>
                </array>
        </dict>
        </array>
    </plist>