Sencha Touch = extJS 3.x or extJS 4.0?

[bardaste]

In my preliminary research phase I already asked for books, but one more thing: I've read that ExtJS 4.0 will be quite different, Sencha Touch 1.0 is more similar to ExtJS 3.x or to ExtJS 4.0 ?

Otherwise said: is it ok to learn sencha touch with extjs 3.x books or it would be better to have a 4.x book? (ok clear, there are no 4.0 books still), but what I mean is: ExtJS 4.0 seems to be a big change that will simplify also the learning curve. If this is true, Sencha Touch is on the 3.x or on the 4.0 side? And even if it is on the 4.0 is there a good argument not to study it with 3.x material?

(it can seem a stupid question but I am short on time so I try to maximize productivity)

[mrsunshine]

Sencha Touch 1.x and ExtJS 4.x have a shared code base, for example data package ad mvc stuff.

[mitchellsimoens]

Sencha Touch isn't like ExtJS. It's foundation was from ExtJS but ExtJS 4 is going to be more like Sencha Touch.

[bardaste]

Ok so since ExtJS 4.0 is round the corner and I can wait some months to start studying may it make sense to wait for at least an ExtJS 4 book (or a Sencha Touch book)?

[mitchellsimoens]

The only ExtJS 4 and ST books that I know of is currently in the early stages of being planned by Jay Garcia. I think he has a TOC written for each but I think that is the furthest he is.

[VinylFox]

The concepts learned in 3.x books will be entirely relevant to 4.x and Touch development.

Your not going to see a 4.x or Touch book for a while, the API's are still not stable enough (well maybe touch) for a book to be written.