Question

I have a simple application that has a single page with a button that invokes the CameraCaptureTask in Windows Phone 7. I use the MVVM pattern for this. My code behind is clean and I have offloaded the button click response to the ViewModel using behaviors. My code looks like this:

 public class MainViewModel : ViewModelBase
{
    private readonly CameraCaptureTask cameraCaptureTask;

    /// <summary>
    ///   Initializes a new instance of the MainViewModel class.
    /// </summary>
    public MainViewModel()
    {
        if (IsInDesignMode)
        {
            // Code runs in Blend --> create design time data.
        }
        else
        {
            cameraCaptureTask = new CameraCaptureTask();
            cameraCaptureTask.Completed += cameraCaptureTask_Completed;
            CaptureCommand = new RelayCommand(() => CaptureImage());
        }
    }

    public RelayCommand CaptureCommand { get; set; }

    private void cameraCaptureTask_Completed(object sender, PhotoResult e)
    {
        if (e == null || e.TaskResult != TaskResult.OK)
        {
            return;
        }
        else
        {
            // TODO
        }
    }

    private object CaptureImage()
    {
        cameraCaptureTask.Show();
        return null;
    }
}

Now when I run my application and hit the button that binds to the ‘CaptureCommand’ RelayCommand, I hit my breakpoint in the ‘CaptureCommand()’ method and it fires the ‘Show()’ method of the CameraCaptureTask resulting in my camera coming up on the device successfully. However once I complete taking a picture and hit ‘Accept’, the ‘cameraCaptureTask_Completed(object sender, Photoresult e)’ event handler never gets invoked. Am I missing something here?

Thanks in advance!

Answer 1

Why are you relaying this when you have just a show?

Try moving the cameraCaptureTask out of the Constructor and into an invoked method