[In need of explaination] Flint & Steel creating a nether portal

[ExcuseMyLuck]

Okay. So I am trying to create a dimension. I have everything working(pretty much), but I am trying to make the portal now. I have been stuck on how flint&steel creates the nether portal. Can anybody explain it to me? The item file is below for reference.

 

[LexManos]

1) Dont post entire mojang classes

2) Flint and Steel dont create the portals, Fire does.

[ExcuseMyLuck]

1) Dont post entire mojang classes

2) Flint and Steel dont create the portals, Fire does.

 

Okay. I wont post full classes anymore. Any then how would I go about making the fire create a portal to my dimension?

[DigitalHeavy]

the portal frame "obsidian" recognizes the fire block which is assigned to the portal block class to make the portal block appear when the fire is lit on the portal frame