tl;dr : Just translate the expression literally, French has the same figurative meanings as English.

French has the same glue and metalwork ideas, in the form of scotch tape and rivets :

 Il est scotché à la télé
Elle est rivée à son ordinateur (she’s riveted)

These are maybe the most idiomatic expressions (but won’t work with all things, e.g. I don’t think you can be *rivée à la TV). There are other variations based on glue (« il passe son temps le nez collé à son écran »).

Most importantly maybe, I find it hard to build a litteral translation from english figurative expressions that wouldn’t be understood in french.
For instance, you can translate "tear/pull away" straightforwardly as « arracher », and it’ll have the same figurative meaning in french.

When not locked in front of a computer, she’s glued to the viewfinder of her camera.
Quand elle n’est pas coincée sur un ordinateur, on ne la décolle pas de son camescope.
Quand elle n’est pas verrouillée à son ordinateur — a bit strange, but will be understood

I finally managed to tear/pull my son away from the TV.
J’ai enfin réussi à l’arracher de la TV.

The book is so engagingly written it is hard to put it down.
Ce livre est tellement bien écrit qu’il est difficile à déposer.

Except "locked", all are very litteral translations, and they sound right in french to express the same idea. Admittedly I, as a native speaker, choose the "right" translations (e.g. « elle est verrouillée à son ordinateur » is not idiomatic, if straightforward to understand), but mostly they all seem to work, and everyone may prefer their own pet sayings.

Adding to @NikanaReklawyks good answer, you can use

• river (être rivé[e]) = put together metal pieces with rivets, and figuratively to keep eyes on.

  When not locked in front of a computer, she’s glued to the viewfinder of her camera.
  Quand elle n’est pas rivée à son ordinateur, elle est collée à son camescope.

• immerger = submerge in liquid or plonger = plunge into a liquid, both will have figuratively the sense of being immersed in an activity.
  With a more neutral meaning than those with lock or glue.

  Je me suis immergé dans ce livre et je n’ai pas vu le temps passer !
  Quand on est plongé dans un film, on peut s’évader dans un nouveau monde.