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QGeoAreaMonitor::createDefaultMonitor returns 0. Strange, no?

  • Hello,

    I have been using the Location API for Qt Mobility in a limited way for some time. Basically, I've been using it to get location. Now I want to use the QGeoAreaMonitor class. While there are a half dozen references which talk about it, they all seem to break down to the same example (chick "here": ). This works with the Qt Simulator but it returns 0 on device which I wasn't expected. Now I'm going to check the tool chain used to compile, the runtime on the Symbian device (N8) and create a testcase. Suggests are welcome especially if you've encountered this problem or used this class.


  • Hello,

    Step one is to check the tool chain.

    QT_VERSION tells me I'm compiling against 4.6.3.

    QTM_VERSION shows I'm using 1.02 of the Qt mobility libraries.

    Step Two. What's on the phone?

    qVersion() tells me I'm running against 4.6.4. I had expected 4.6.3 but OK.

    fortunately, I had a fresh N8 around. During installing, the installer told me it was installing 1.0.2

    the firmware is 011.012 which I think is the latest.

    I guess it is time for a testcase.


  • The createDefaultMonitor() function returns 0 if there isn't a way to do distance based triggering on the device. This will be the case for most (possibly all) Symbian 5th edtion phones, but it should be fine on the N8.

    My understanding is that the required library (LBT) is available by default on Symbian^3. Are you able to try building Qt Mobility from source and checking if LBT is getting picked up during the configure step?

  • Hello David,

    Thanks for your informative response.

    bq. Are you able to try building Qt Mobility from source and checking if LBT is getting picked up during the configure step?

    This is trivial on Linux. Symbian Signing and Windows makes this a pain. The functionality I need for this app is limited. It may make sense for me to implement this functionality.


  • Hi johnk,

    did you follow up on this? I'm having the same problem with Qt 4.7.2 and Qt Mobility 1.1 on the Nokia C7. Maybe the problem is, that I'm using the Symbian^1 SDK for building?

    There's a thread on Forum Nokia as well, unfortunately also without a solution.

  • There's a bug for this:

    We're looking into it, although it's too soon to know how long it will take to fix. The code was accidentally disabled quite some time ago, and has subsequently missed on out on some TLC that the position and satellite info source code has received.

  • Thanks David, I'm subscribed to this bug now.
    I also just noticed that I don't even get normal position updates on my C7, but that will be another thread...

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