Allow Up/Down Arrow to Scroll

src/main/java/com/nomiceu/nomilabs/mixin/betterp2p/GuiAdvancedMemoryCardMixin.java

@@ -2,6 +2,7 @@
 
 import net.minecraft.client.gui.GuiScreen;
 
+import org.lwjgl.input.Keyboard;
 import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Shadow;
@@ -25,7 +26,7 @@
 
 /**
  * Allows accessing needed functions and fields, and initializes playerPos field in InfoList. Also fills up
- * LabsClientCache.
+ * LabsClientCache, calls proper resetting of scrollbar in custom places, and allows arrows to scroll.
  */
 @Mixin(value = GuiAdvancedMemoryCard.class, remap = false)
 public abstract class GuiAdvancedMemoryCardMixin extends GuiScreen implements AccessibleGuiAdvancedMemoryCard {
@@ -99,6 +100,19 @@ private void properlyResetScrollbarFilterClear(int mouseX, int mouseY, int mouse
         labs$properlyResetScrollbar();
     }
 
+    @Inject(method = "keyTyped", at = @At("HEAD"), cancellable = true, remap = true)
+    private void allowArrowScroll(char typedChar, int keyCode, CallbackInfo ci) {
+        if (keyCode == Keyboard.KEY_UP) {
+            scrollBar.wheel(1);
+            ci.cancel();
+            return;
+        }
+        if (keyCode == Keyboard.KEY_DOWN) {
+            scrollBar.wheel(-1);
+            ci.cancel();
+        }
+    }
+
     @Inject(method = "keyTyped",
             at = @At(value = "INVOKE",
                      target = "Lcom/projecturanus/betterp2p/client/gui/InfoList;refilter()V",