Add internal FabricItemGroup class

Relates to Sinytra/Connector#839

fabric-item-group-api-v1/src/client/java/net/fabricmc/fabric/mixin/itemgroup/client/CreativeInventoryScreenMixin.java

@@ -20,6 +20,8 @@
 
 import net.fabricmc.fabric.impl.client.itemgroup.FabricCreativeGuiComponents;
 
+import net.fabricmc.fabric.impl.itemgroup.FabricItemGroup;
+
 import net.minecraft.item.ItemGroups;
 
 import net.minecraftforge.client.gui.CreativeTabsScreenPage;
@@ -31,7 +33,12 @@
 import net.minecraft.item.ItemGroup;
 
 import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+import org.spongepowered.asm.mixin.injection.callback.LocalCapture;
 
+import java.util.Iterator;
 import java.util.List;
 import java.util.Objects;
 
@@ -59,6 +66,11 @@ private static int fabric_getPage() {
 		return fabric_currentPage;
 	}
 
+	@Inject(method = "init", at = @At(value = "INVOKE", target = "Ljava/util/List;add(Ljava/lang/Object;)Z", ordinal = 0), locals = LocalCapture.CAPTURE_FAILHARD)
+	private void initPages(CallbackInfo ci, int tabIndex, List<ItemGroup> currentPage, Iterator<?> it, ItemGroup sortedCreativeModeTab) {
+		((FabricItemGroup) sortedCreativeModeTab).setPage(this.pages.size());
+	}
+
 	@Override
 	public void fabric_previousPage() {
 		this.setCurrentPage(this.pages.get(Math.max(this.pages.indexOf(this.currentPage) - 1, 0)));

fabric-item-group-api-v1/src/main/java/net/fabricmc/fabric/impl/itemgroup/FabricItemGroup.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2016, 2017, 2018, 2019 FabricMC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.fabricmc.fabric.impl.itemgroup;
+
+public interface FabricItemGroup {
+	int getPage();
+
+	void setPage(int page);
+}

fabric-item-group-api-v1/src/main/java/net/fabricmc/fabric/impl/itemgroup/FabricItemGroupBuilderImpl.java

@@ -24,7 +24,7 @@ public final class FabricItemGroupBuilderImpl extends ItemGroup.Builder {
 
 	public FabricItemGroupBuilderImpl() {
 		// Set when building.
-		super(null, -1);
+		super(ItemGroup.Row.TOP, -1);
 	}
 
 	@Override

fabric-item-group-api-v1/src/main/java/net/fabricmc/fabric/mixin/itemgroup/ItemGroupMixin.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2016, 2017, 2018, 2019 FabricMC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.fabricmc.fabric.mixin.itemgroup;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Unique;
+
+import net.minecraft.item.ItemGroup;
+
+import net.fabricmc.fabric.impl.itemgroup.FabricItemGroup;
+
+@Mixin(ItemGroup.class)
+abstract class ItemGroupMixin implements FabricItemGroup {
+	@Unique
+	private int fabric_page = -1;
+
+	@Override
+	public int getPage() {
+		if (fabric_page < 0) {
+			throw new IllegalStateException("Item group has no page");
+		}
+
+		return fabric_page;
+	}
+
+	@Override
+	public void setPage(int page) {
+		this.fabric_page = page;
+	}
+}

fabric-item-group-api-v1/src/main/resources/fabric-item-group-api-v1.mixins.json

@@ -0,0 +1,11 @@
+{
+  "required": true,
+  "package": "net.fabricmc.fabric.mixin.itemgroup",
+  "compatibilityLevel": "JAVA_17",
+  "mixins": [
+    "ItemGroupMixin"
+  ],
+  "injectors": {
+    "defaultRequire": 1
+  }
+}

fabric-item-group-api-v1/src/main/resources/fabric.mod.json

@@ -21,6 +21,7 @@
   },
   "description": "An API for adding custom item groups.",
   "mixins": [
+    "fabric-item-group-api-v1.mixins.json",
     {
       "config": "fabric-item-group-api-v1.client.mixins.json",
       "environment": "client"

gradle.properties

@@ -69,5 +69,5 @@ fabric-client-tags-api-v1-version=1.1.2
 loom.platform=forge
 forge_version=1.20.1-47.2.6
 pack_format=15
-forgified_version=1.11.2
+forgified_version=1.11.3
 forge_fabric_loader_version=2.6.0+0.15.0+1.20.1