Here's all the info you need for taming:
1. It takes 30 minutes of actual time to tame an animal. That's total. it doesn't have to be continuous.
2. They must be fed and not frightened, either by you or another creature
3. You must be in the area. Think of it like you're the workbench when it comes to taming.
If you leave the area taming will be put on hold. As said above you'll see little yellow hearts when the taming process is going on.
4. Know what to feed them when taming: Boars like mushrooms (red only), raspberries, and blueberries. Probably cloudberries too but I've never tried that. Wolves like raw meat but won't eat wolf meat, they're classy that way. I've seen them eat some cooked meat too but raw is best. Lox love cloudberries.
5. You can build an enclosure for taming Boars. Wolves work better with a taming pit since they destroy stuff fast. Lox you can actually tame just by staying near and sneaking since their sight and hearing are pretty bad.