Shelf blocks useless in pocket edition

This is working as intended. Players must load the shelves with items first, before powering the shelf to enable quick hot bar swapping.

Hi!
Thank you for your report!
However, this issue is Working as Intended.

Please note, that mechanics of the game may change between updates.
Things such as graphics, sounds, world creation, biomes, redstone, villagers, and animals may not work the same in current versions.

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Oh my bad