Challenge #5
From our previous post, we know that if we try to collect items on the OnStart property of the app, the collection doesn't get populated. However, if we test the same situation within the app designer, it is very common to manually run OnStart to "emulate" using the app within the model-driven form (typically so that the rest of the logic within the app can be tested). If we run the OnStart of the app manually within the designer, it seems as there is no issue with the collection process.
Trick #5
The trick is as simple as this: simply do not test an embedded canvas app within the app designer. Always make changes, save & publish the app, and then test it from within the model-driven form. Testing within the model-driven form, in this case, shows that no items get collected.
Have fun! Get addicted!