Help me with doing a inventory block (I solved that already)

I am doing block that works similar to the Smithing Table, it has 2 input slots, 1 output slot and a button. I want to make button clear input slots and give item in output.

But when I made procedure for that, it don't letting me to put it in trigger "When button is pressed". It says "not enough dependencies" while it has all but not "guistate". Please help me how to do that correctly! I watched guides, they don't say anything about that!

Edited: Ok, I did that faster than i though (literally 30 seconds after i posted this topic). I just used the wrong item checks for slots. Always use GUI item checks! Thats why most of inventory blocks can't work.