Hey I was thinking that it could be great if forge can handle these 2 events

 

They would be called when a slot from the player inventory or armor inventory changed

 

Because actually, the only way I found to check armor changes is to check the player stuff every tick, which is quite hardcodded

 

(I hope my English wasn't too awful)

It's not hard to check. PlayerTickEvent or LivingUpdateEvent, with a flag set to true. It would look something like this:

 

private boolean flag = true;

@SubscribeEvent
public void onPlayerTick(TickEvent.PlayerTickEvent event)
{
if(event.phase == TickEvent.Phase.START && event.side == Side.SERVER)
{
	if(flag)
	{
		if(event.player.inventory.armorInventory[0] == MyItem)
		{
			flag = false;
			// DO STUFF
		}
	}
	else
	{
		if(event.player.inventory.armorInventory[0] == null)
		{
			flag = true;
		}
	}
}
}

 

This is a very minimal amount of processing required to be done every tick, I doubt it would ever interfere with performance.

public Item[] armor = new Item[4];


public void updateArmor()
{
	 for (int i = 0; i < 4; i++)
	 {
		 ItemStack is = this.player.inventory.armorInventory[i];
		 if (is != null)
		 {
			 Item item = is.getItem();
			 if (item != this.armor[i])
			 {
				 if (item instanceof ItemArmorM)
				 {
                                                  //the player equipped my item
				 }
				 this.armor[i] = item;
			 }	 
		 }
		 else if (is == null && this.armor[i] != null)
		 {
			 if (this.armor[i] instanceof ItemArmorM)
			 {
                                        //The player unequipped my item
			 }
			 this.armor[i] = null;
		 }
	 }		
}

 

I never said this code was hard to made...

 

I'm just suggesting to create this event, which would necessarily improve game performance

 

EDIT: i mean, if a player install 10 armor mods, it is non sense checking this 10 differents times

A more effective solution would be:

A. add an event PlayerEvent.armorChangeEvent with properties Item oldArmor, newArmor

B. Post the even in these methods:

• InventoryPlayer#clearInventory - armor removed
  
• InventoryPlayer#copyInventory - armor changed
  
• InventoryPlayer#damageArmor - armor removed (if damaged beyond repair)
  
• InventoryPlayer#decrStackSize - when stack is armorInventory slot
  
• InventoryPlayer#dropAllItems - obviously, armor removed
  
• InventoryPlayer#getStackInSlotOnClosing - why this removes armor is a mystery
  
• InventoryPlayer#setInventorySlotContents - change, add, or remove
  
• InventoryPlayer#readFromNBT - donning armor
  

 

Then armor can listen for the change and add/remove effects.