Good day together,

 

I am quite new to Forge and still learning its API. I was creating an EventHandler for the PlayerInteractEvent.RightClickBlock event to run some logic there. The ultimate goal is to implement right click crop harvesting as a little exercise to the event system. The harvesting itself is working without problems, though when I have a BlockItem (like dirt) in my main Hand and right click on the crop, the harvest logic runs, but also the dirt block is placed for a frame in the world and then vanishes as well as getting removed from my inventory. For debugging purposes I created this EventHandler:

 

@SubscribeEvent(priority = EventPriority.HIGHEST)
public void onRightClickBlock(PlayerInteractEvent.RightClickBlock event) {

    final PlayerEntity playerEntity = event.getEntityPlayer();

    if (playerEntity == null) {
        return;
    }

    if (playerEntity.getHeldItem(event.getHand()).getItem() instanceof BlockItem) {
        event.setUseItem(Event.Result.DENY);
        event.setUseBlock(Event.Result.DENY);
    }
}

 

I expected this code to prevent all kinds of block placing, but whenever I right-click with a BlockItem in my main hand to place it, it appears for a frame and then vanishes from the world (and my inventory). Did I misunderstand the use of the event.setUseBlock/Item methods? I would really appreciate some help

 

Greetings SamuelYaron

Edited July 15, 20196 yr by SamuelYaron

My guess to what's happening here is the handler is canceling the event, but only after Vanilla has done its thing.

Maybe you need to target which side Client/Server you subscribe the event?

Hm, in my original code I abort the event handling if the world is remote. Is that what you mean? In that case it would not help. Here is my original EventHandler code:

 

@SubscribeEvent
public void rightClickHarvest(PlayerInteractEvent.RightClickBlock event) {
    final PlayerEntity playerEntity = event.getEntityPlayer();

    if(playerEntity == null) {
        return;
    }

    if(event.getWorld().isRemote) return;

    final BlockState blockState = event.getWorld().getBlockState(event.getPos());

    if (!(blockState.getBlock() instanceof CropsBlock) || playerEntity.getHeldItemMainhand().canHarvestBlock(blockState) || playerEntity.getHeldItemOffhand().canHarvestBlock(blockState)) {
        return;
    }

    if (playerEntity.getHeldItem(event.getHand()).getItem() instanceof BlockItem) {
        event.setUseItem(Event.Result.DENY);
        event.setUseBlock(Event.Result.DENY);
    }

    if (event.getHand() != Hand.MAIN_HAND) {
        return;
    }

    if(canHarvest(blockState)) {
        playerEntity.swingArm(Hand.MAIN_HAND);
        if (!event.getWorld().isRemote) {
            harvest(blockState, event.getPos(), event.getWorld(), playerEntity);
        }
    }
}

I just started the Minecraft development Instance with the debugger to verify that my event handler (the code from my first posting) fires before any logic that results in placing/removing my block from the world or the inventory.

 

And indeed the handler runs and the interaction result is a pass. The following networking code is beyond my capabilities at the moment. So if anyone has any more ideas or hints I would appreciate it. Otherwise I will be trying to analyze the runtime behavior and share my results if they are of any note.

Edited July 14, 20196 yr by SamuelYaron

@PhilipChonacky As far as I understand this event only fires on the server. A quick test with some debug statements also verifies that.

 

I tried to dig through all this network code for some time now, but it is hard to grasp as a newbie to the architecture. I have the suspicion though that my problem is connected to these two issues:

 

https://github.com/MinecraftForge/MinecraftForge/issues/5802

https://github.com/MinecraftForge/MinecraftForge/issues/3272

40 minutes ago, SamuelYaron said:

As far as I understand this event only fires on the server. A quick test with some debug statements also verifies that.

And that's what causes the behavior. The event--not firing on the client--isn't canceled on the client, so the default (block is placed) behavior takes over and places the block. Then the packet data comes back from the server and says "that space is air" and the block vanishes again.

Thanks for the clarification and explanation of whats going on! Though it does not solve the original problem for me I know now about this particular behavior and can consider it while coding.

 

I did not see any option for editing the topics name, but for me this issue is solved and could be marked as such.

 

Thanks again

2 hours ago, SamuelYaron said:

I did not see any option for editing the topics name

Edit the first post and you can edit the title.