public class OpenFiltListScreenC2SPacket {
    private FriendlyByteBuf buf;
    public OpenFiltListScreenC2SPacket(){}
    public OpenFiltListScreenC2SPacket(FriendlyByteBuf buf){
        this.buf = buf;
    }
    public void encode(FriendlyByteBuf buf){}
    public void handle(Supplier<NetworkEvent.Context> supplier){
        NetworkEvent.Context context = supplier.get();
        context.enqueueWork(()->{
            context.getSender().getCapability(FiltListProvider.FILT_LIST).ifPresent(serverFiltList -> {
                //Server Logic
                context.getSender().sendSystemMessage(Component.literal("Open Screen"));
                NetworkHooks.openScreen(context.getSender(), new SimpleMenuProvider(
                        (containerId, playerInventory, player) -> new Menu(containerId, playerInventory, buf),
                        Component.translatable("menu.title.filtpick")));

            });
        });
        context.setPacketHandled(true);
    }
}

public class Menu extends AbstractContainerMenu {
    private Inventory inventory;
    private final Level level;
    private static final DeferredRegister<MenuType<?>> REGISTER = DeferredRegister.create(ForgeRegistries.MENU_TYPES, FiltPick.MOD_ID);
    public static final RegistryObject<MenuType<Menu>> MENU_TYPE = REGISTER.register("filtlist", ()-> IForgeMenuType.create(Menu::new));


    // Client menu constructor
    public Menu(int containerId, Inventory playerInventory, FriendlyByteBuf buf) {
        this(containerId, playerInventory, new ItemStackHandler(27), new SimpleContainerData(2));
    }

    // Server menu constructor
    public Menu(int containerId, Inventory playerInventory, IItemHandler dataInventory, SimpleContainerData  dataMultiple) {
        super(MENU_TYPE.get(),containerId);
        checkContainerSize(playerInventory,2);
        this.level = playerInventory.player.level;
        // Check if the data inventory size is some fixed value
        // Then, add slots for data inventory
        this.addSlot(new SlotItemHandler(dataInventory, 0, 0, 0));

        // Add slots for player inventory
        this.addSlot(new Slot(playerInventory, 0, 0 ,0));

        // Add data slots for handled integers
        this.addDataSlots(dataMultiple);

        // ...
    }


    @Override
    public ItemStack quickMoveStack(Player player, int quickMovedSlotIndex) {
        return ItemStack.EMPTY;
    }

    @Override
    public boolean stillValid(Player player) {
        return true;
    }
}

public class FiltContainerScreen extends AbstractContainerScreen<Menu> {


    public FiltContainerScreen(Menu menu, Inventory playerInventory, Component title) {
        super(menu, playerInventory, title);

        this.titleLabelX = 10;
        this.inventoryLabelX = 10;
    }

    @Override
    protected void init() {
        super.init();

    }


    @Override
    public void render(PoseStack pose, int mouseX, int mouseY, float partialTick) {
        this.renderBackground(pose);
        super.render(pose, mouseX, mouseY, partialTick);

        /*
         * This method is added by the container screen to render
         * a tooltip for whatever slot is hovered over.
         */
        this.renderTooltip(pose, mouseX, mouseY);
    }

    @Override
    protected void renderBg(PoseStack pose, float p_97788_, int p_97789_, int p_97790_) {
        /*
         * Sets the texture location for the shader to use. While up to
         * 12 textures can be set, the shader used within 'blit' only
         * looks at the first texture index.
         */
        RenderSystem.setShaderTexture(0, BACKGROUND_LOCATION);

        /*
         * Renders the background texture to the screen. 'leftPos' and
         * 'topPos' should already represent the top left corner of where
         * the texture should be rendered as it was precomputed from the
         * 'imageWidth' and 'imageHeight'. The two zeros represent the
         * integer u/v coordinates inside the 256 x 256 PNG file.
         */
        this.blit(pose, this.leftPos, this.topPos, 0, 0, this.imageWidth, this.imageHeight);
    }
}

    @Mod.EventBusSubscriber(modid = FiltPick.MOD_ID, value = Dist.CLIENT, bus = Mod.EventBusSubscriber.Bus.MOD)
    public class ClientModEvents{
        @SubscribeEvent
        public static void onKeyRegister(RegisterKeyMappingsEvent event){
            event.register(KeyBinding.SET_ITEM_MAP);
            event.register(KeyBinding.OPEN_FILTLIST_MAP);
        }

        @SubscribeEvent
        public static void gatherData(GatherDataEvent event) {

        }
        @SubscribeEvent
        public static void clientSetup(FMLClientSetupEvent event) {
            event.enqueueWork(
                    // Assume RegistryObject<MenuType<MyMenu>> MY_MENU
                    // Assume MyContainerScreen<MyMenu> which takes in three parameters
                    () -> MenuScreens.register(Menu.MENU_TYPE.get(), FiltContainerScreen::new)
            );
        }
    }

This is what I want to implement:
When I press a key, client will sent the above packet to server, then the server will make my client to open the screen.
But:
My client only gets the systemMessage, "Open Screen", but no screen is opened... Why?

Is this your entire codebase? Have you added the `DeferredRegister` to the mod event bus via `#register`? Where are you sending the packet to the server? Why do you need a `FriendlyByteBuf` when you aren't sending any data?

22 hours ago, ChampionAsh5357 said:

Is this your entire codebase? Have you added the `DeferredRegister` to the mod event bus via `#register`? Where are you sending the packet to the server? Why do you need a `FriendlyByteBuf` when you aren't sending any data?

This is not my entire codebase. I haven't added the `DeferredRegister` to the mod event bus via `#register` and I think this is where the problem is. I send the packet via keybinding, when I press a key, the packet will be sent. I haven't used `FriendlyByteBuf` because I am still studying how to use it.

UPDATE:
I made it after I added "Menu.REGISTER.register(FMLJavaModLoadingContext.get().getModEventBus());" in the main entry. Thanks.

Edited May 21, 20232 yr by Xie Peng