Just like the arrows in the picture
Lever and Redstone are not in contact with Dropper's location
But when Sticky Piston pushed Iron Bars to the front of Dropper
Dropper is activated
In the picture【发射器：发射失败】=【Dropper:Launch failure】
I had thought that this would lead to a target location Redstone circuits are activated
But when i use Redstone Lamp or even TNT test
They will not be triggered
But only Dropper will be activated