in a watch there are 2 different things, one is the movement and the other one is the "habillage"(case, dials, straps, buckles etc)
for the movement serious swiss watchmakers are doing their components themselves or outsourced but in switzerland, to me, it does't make a difference in the end as long as they control the quality of those components and they apply their decoration and finishing level, a lot of them are doing this. All of them have the same problems with the spirals springs since it is very complicated to manage, means to have the same spirals of the same quality all the time. A lot of brands buys them directly from nivarox (eta) or so (they are not many factory which produce it). I don't know who except PP and RD are producing their own ones.
For the "habillage" that is a really different story. A lot of brands are buying their components directly in Asia. I won't tell you what i know but many brands people consider well are doing so BUT, sometimes you can't blame them cause for example for sapphire case (very very often) most of the cases you see on the market are produced in China, the price is better but that ain't the problem, the main issue is that swiss company just didn't wanted to make it or wouldn't dare at the time it started and now for what i know Chineses sapphire company can achive better and more advanced results in this domain.