Yes you do have to pull the trigger to break a Glock down.
Step 1 - Clear the Gun.
Step 2 - Repeat Step 1
Step 3 - Pull Trigger (If at the range I do it pointed down range, or a the clearing barrel)
Step 4 - Pull the takedown lever down will holding the slide SLIGHTLY out of battery. If you pull to far back go back to step 1, it is again at "half-cock".
Step 5 - Holding takedown lever down move the slide foward, until off the lower.
Step 6 - Remove spring/guide rod
Step 7 - Remove barrel
to re-assmeble start at step 7 work back to step 5
Yes Glock is different, 34 total parts, trigger pull can be adjusted by simply changing a $2.00 spring. Some parts even interchange between different caliber guns.
Oh, for all you "safety lever" guys, how many safeties on a revolver?
Berretta makes the gun tha is supposed to dis-assemble so easy that someone standing on the business end can steal your slide...Glock won't do that.