Beginning Collection Views · Deleting Courses Using Snapshots |

This is a companion discussion topic for the original entry at

@pasanpr, could you please give a brief description what snapshot is.

@pasanpr Can you please help with this when you get a chance? Thank you - much appreciated! :]

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The best way to describe it is “what your data looks like at any given moment”. Let’s look at a simple example where our initial data is 0 0 0 0. In this example let’s say that our data changes every second by shifting in 1 from the right. For the next 5 seconds we have 5 snapshots of data each of which look like this:

1: 0 0 0 0
2: 0 0 0 1
3: 0 0 1 1
4: 0 1 1 1
5: 1 1 1 1

In our apps the data doesn’t necessarily change based on time, but it can based on user interaction. Whenever a user takes an action we look at how the data was modified and we “freeze” that data at that point to create a snapshot. Hope this helps!

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Thank you! Much more clear now! :smiley:

There is a possible bug in the QueuedTutorialController regarding delete feature. After deleting a course, switch back to queue tab and come back again. That deleted course will be back in queue. I think that’s because “isQueued” property of Tutorial is not set to false after deleting it from queue.

I don’t know if this is the intended behaviour but I just wanted to mention just in case.

It is not the intended behavior, more of an incomplete implementation since it was outside the scope of the course. Thanks for flagging though!