I am having an issues finding documentation or assistance in working with item frames. I write this post after three days of not finding so much as one page or discussion on even the basics of item frames. A search on these forums returns only crashlogs in an almost unreadable search response. Here is my situation and question:
In my current project, upon a player walking on a custom block, which I will call the 'key' block, I check the blocks near this key block to determine if the player has built a structure to proper arrangement - a properly built multi-block structure. If the structure is not properly built, then following methods (teleportation in this case) will not occur. Determining a block type by location is simple and well documented, and I have had no issues checking for a proper build of blocks.
if (world.getBlock(x + 0, y + 2, z + 1) == Blocks.quartz_block)
...where x,y,z is the key block location, triggered by the onEntityWalking event in the custom key block.
However, I would like one of the required units to be an item frame, but how do I check for an item frame relative to the key block? I've tried several get properties and conversions, but to no avail. I believe I need to find an EntityItemFrame, but there has to be a simple answer. The 'block' returns as air, for example. Also I want to determine if the contents of the item frame match a certain criteria, and I imagine I will have that question as well when I get there.
Any help would be appreciated.