Beginner at XCODE 9

If I understand your goal, that's how I would do it (just a sketch of how I would do, not a full implementation).

The back image would be in a scrollView.

Do you want to see a picture as well in the front ? If so, the front image would be a mozaic of smaller images: their size depend on the number of holes you want to see through.

For instance: 5*4 or 4*5 (depending portrait or landscape).

All those sub-images would be part of a larger one, so that they fit seemlessly together.

For some images, you should set the alpha channel to 0.2 to make it quasi transparent.

Note: this could be a variable value, if you want to be able to change transparency level.

The prder in which you include the views make them front or back.

Add a gesture recognizer to the sub image ; it will scroll behind and be visible through the transparent parts.

Good luck.

He's not a programmer -- he won't know what you're talking about. He needs to learn basic programming skills first. There are lots of tutorials on that.

You are probably right.

So, a good starting point is found in iBooks library:

App development with Swift

or

Intro to App development with Swift

I find also that it is good, when learning, to have a goal in mind for an App ; that helps focus one's attention on what we read.

Hello and thanks for comments.

I'm learning as I try to do exercises with xcode.

My goal is the following:

I need to put a picture in backside on a scroll view and then in front another picture with some parts hidden to permit me to see the picture on back.

I've succeed to do this using a table on the scroll view. I can slide the table on back even with the picture object in frnot.

But when i want to do the same using a picture instead of table on the back scroll view. I can't slide the back picture.