Fatal Error With GuiFactory

[Poipt]

Hi, I'm trying to create a mod for Minecraft 1.8.9 that allows you to zoom in with a keypress. For my GuiFactory, I am having a number input that allows you to customize the amount to zoom in by. So far, I have followed Jabelar's tutorial about GuiFactories, but whenever I open the config for my mod, I get this error:

[12:36:22] [Client thread/ERROR] [FML]: There was a critical issue trying to build the config GUI for fovmod
java.lang.reflect.InvocationTargetException
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_91]
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) ~[?:1.8.0_91]
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) ~[?:1.8.0_91]
	at java.lang.reflect.Constructor.newInstance(Unknown Source) ~[?:1.8.0_91]
	at net.minecraftforge.fml.client.GuiModList.actionPerformed(GuiModList.java:293) [GuiModList.class:?]
	at net.minecraft.client.gui.GuiScreen.mouseClicked(GuiScreen.java:509) [GuiScreen.class:?]
	at net.minecraftforge.fml.client.GuiModList.mouseClicked(GuiModList.java:197) [GuiModList.class:?]
	at net.minecraft.client.gui.GuiScreen.handleMouseInput(GuiScreen.java:621) [GuiScreen.class:?]
	at net.minecraft.client.gui.GuiScreen.handleInput(GuiScreen.java:587) [GuiScreen.class:?]
	at net.minecraft.client.Minecraft.runTick(Minecraft.java:1761) [Minecraft.class:?]
	at net.minecraft.client.Minecraft.runGameLoop(Minecraft.java:1080) [Minecraft.class:?]
	at net.minecraft.client.Minecraft.run(Minecraft.java:380) [Minecraft.class:?]
	at net.minecraft.client.main.Main.main(Main.java:116) [Main.class:?]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_91]
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_91]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_91]
	at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_91]
	at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?]
	at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_91]
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_91]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_91]
	at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_91]
	at net.minecraftforge.gradle.GradleStartCommon.launch(GradleStartCommon.java:97) [start/:?]
	at GradleStart.main(GradleStart.java:26) [start/:?]
Caused by: java.lang.NullPointerException
	at fovmod.gui.FOVGuiConfig.<init>(FOVGuiConfig.java:26) ~[FOVGuiConfig.class:?]
	... 25 more

Here is my GuiFactory code:

package fovmod.gui;

import java.util.HashSet;
import java.util.Set;

import net.minecraft.client.Minecraft;
import net.minecraft.client.gui.GuiScreen;
import net.minecraftforge.fml.client.IModGuiFactory;

public class FOVGuiFactory implements IModGuiFactory 
{
    @Override
    public void initialize(Minecraft minecraftInstance) 
    {
 
    }
 
    @Override
    public Class<? extends GuiScreen> mainConfigGuiClass() 
    {
        return FOVGuiConfig.class;
    }
 
    @Override
    public Set<RuntimeOptionCategoryElement> runtimeGuiCategories() 
    {
    	return null;
    }
 
    @Override
    public RuntimeOptionGuiHandler getHandlerFor(RuntimeOptionCategoryElement element) 
    {
        return null;
    }
}

And here is my config code (I do not have a tutorial for my number input yet, so if you could also point me in the direction of a tutorial to do that, that would be great):

package fovmod.gui;

import fovmod.FOVMod;
import fovmod.Reference;
import net.minecraft.client.gui.GuiButton;
import net.minecraft.client.gui.GuiScreen;
import net.minecraft.client.resources.I18n;
import net.minecraft.util.ChatComponentText;
import net.minecraftforge.common.MinecraftForge;
import net.minecraftforge.common.config.ConfigElement;
import net.minecraftforge.common.config.Configuration;
import net.minecraftforge.fml.client.config.GuiMessageDialog;
import net.minecraftforge.fml.client.event.ConfigChangedEvent;
import net.minecraftforge.fml.client.event.ConfigChangedEvent.OnConfigChangedEvent;
import net.minecraftforge.fml.client.event.ConfigChangedEvent.PostConfigChangedEvent;
import net.minecraftforge.fml.common.FMLCommonHandler;
import net.minecraftforge.fml.common.Loader;
import net.minecraftforge.fml.common.eventhandler.Event.Result;
import net.minecraftforge.fml.client.IModGuiFactory;

public class FOVGuiConfig extends net.minecraftforge.fml.client.config.GuiConfig 
{
    public FOVGuiConfig(GuiScreen parentScreen) 
    {
        super(parentScreen, new ConfigElement(Reference.config.getCategory(Configuration.CATEGORY_GENERAL)).getChildElements(), Reference.MODID, false, false, "test");
    }
    @Override
    public void drawScreen(int mouseX, int mouseY, float partialTicks)
    {
    	title = "test";
    	super.drawScreen(mouseX, mouseY, partialTicks);
    }
    
    @Override
    protected void actionPerformed(GuiButton button)
    {
        if (button.id == 2000)
        {
        	System.out.println("Pressed DONE button");
            boolean flag = true;
            try
            {
                if ((configID != null || parentScreen == null || !(parentScreen instanceof FOVGuiConfig)) 
                        && (entryList.hasChangedEntry(true)))
                {
                	System.out.println("Saving config elements");
                    boolean requiresMcRestart = entryList.saveConfigElements();

                    if (Loader.isModLoaded(modID))
                    {
                        ConfigChangedEvent event = new OnConfigChangedEvent(modID, configID, isWorldRunning, requiresMcRestart);
                        MinecraftForge.EVENT_BUS.post(event);
                        if (!event.getResult().equals(Result.DENY))
                            MinecraftForge.EVENT_BUS.post(new PostConfigChangedEvent(modID, configID, isWorldRunning, requiresMcRestart));
                        
                        if (requiresMcRestart)
                        {
                            flag = false;
                            mc.displayGuiScreen(new GuiMessageDialog(parentScreen, "fml.configgui.gameRestartTitle", 
                                    new ChatComponentText(I18n.format("fml.configgui.gameRestartRequired")), "fml.configgui.confirmRestartMessage"));
                        }
                        
                        if (parentScreen instanceof FOVGuiConfig)
                            ((FOVGuiConfig) parentScreen).needsRefresh = true;
                    }
                }
            }
            catch (Throwable e)
            {
                e.printStackTrace();
            }
            
            if (flag)
                mc.displayGuiScreen(parentScreen);
        }
    }    
}

Thank you so much! If you have any questions, let me know.

Edited April 22, 2018 by Poipt

[Draco18s]

53 minutes ago, Poipt said:

@Override public Set<RuntimeOptionCategoryElement> runtimeGuiCategories() {
    return null;
}

@Override
public RuntimeOptionGuiHandler getHandlerFor(RuntimeOptionCategoryElement element) {
    return null;
}

 

This does not seem correct to me.

[Poipt]

OK, I crosschecked my code with some examples, and there were a few things missing. I added those things, but I am still getting the same error.

 

EDIT: I fixed it! The problem was that I didn't have a config file set up.

Edited April 22, 2018 by Poipt