Table of Contents

Getting Started

This guide walks you through installing S1API and creating a minimal Phone App, inspired by the original VitePress docs and the S1NotesApp example.

Installation Guide

This guide covers how to install S1API for both mod users and mod developers.

For Mod Users

If you're a player who wants to use mods that require S1API, follow these steps:

  1. Install MelonLoader

    • Download and install MelonLoader for Schedule One following the official MelonLoader installation guide.
    • Ensure MelonLoader is properly installed by launching the game once and verifying a Plugins folder was created in your game directory.

  2. Install S1API

    • Download the latest S1API release ZIP file.
    • Drag the Plugins folder into your Schedule One game directory.
    • If prompted to replace files, select "Yes". This should only occur when updating S1API.

  3. Verify Installation

    • Launch Schedule One.
    • If installed correctly, S1API will load with MelonLoader at game startup.
    • You can verify the installation by checking the MelonLoader console for S1API messages.

For Mod Developers

For the quickest way to get started making a mod with S1API, you can use the S1APITemplate project.

For a more manual approach, follow these steps:

  1. Obtain S1API.Forked

    • Install S1API.Forked following the steps in the "For Mod Users" section above.

  2. Add S1API.Forked as a Reference

    • Install the S1API.Forked NuGet package in your mod project:
      • Using NuGet Package Manager: Search for "S1API.Forked" and install the latest version
      • Using Package Manager Console: Install-Package S1API.Forked
      • Using .NET CLI: dotnet add package S1API.Forked
      • Using PackageReference: Add <PackageReference Include="S1API.Forked" /> to your project file
    • The NuGet package automatically handles the correct references for both IL2CPP and Mono builds

    Important Warning: Do not add the game's Assembly-CSharp.dll as a reference when using S1API.Forked unless you know what you are doing. Referencing the game's assembly directly loses the cross compatability of the API.

  3. Start Developing

    • You can now use the S1API classes and methods in your mod code.
    • Import the appropriate namespaces in your code files to access S1API functionality.

  4. Publishing Your Mod

    • When publishing your mod, always include S1API as a dependency in your documentation.
    • Make it clear to users that they need to install S1API for your mod to function properly.

Create your first Phone App

  1. Derive from S1API.PhoneApp.PhoneApp:
using UnityEngine;
using UnityEngine.UI;
using S1API.PhoneApp;
using S1API.UI;

public class HelloWorldApp : PhoneApp
{
    public static HelloWorldApp Instance;
    protected override string AppName => "HelloWorld";
    protected override string AppTitle => "Hello World";
    protected override string IconLabel => "Hello";
    protected override string IconFileName => "hello.png"; // put this image next to your mod dll

    protected override void OnCreated()
    {
        base.OnCreated();
        Instance = this;
    }

    protected override void OnCreatedUI(GameObject container)
    {
        var panel = UIFactory.Panel("MainPanel", container.transform, new Color(0.1f, 0.1f, 0.1f), fullAnchor: true);
        UIFactory.Text("Title", "📱 Hello, S1API!", panel.transform, 22, TextAnchor.MiddleCenter);
    }
}
  1. No manual registration needed
  • S1API auto-discovers and instantiates PhoneApp subclasses when the phone HomeScreen starts.
  • Ensure your app class is public.
  1. Build and drop your mod DLL alongside your icon file.

Launch the game. Your app icon should appear on the phone; clicking it opens your custom panel.

Saving data (Saveables)

Annotate fields with SaveableField in classes inheriting Saveable. S1API will save/load JSON per save slot.

using S1API.Internal.Abstraction;
using S1API.Saveables;

public class MySaveData : Saveable
{
    [SaveableField("notes-config")] private NotesConfig _config = new NotesConfig();

    protected override void OnLoaded() { /* apply config */ }
    protected override void OnSaved()  { /* flush caches */ }
}

Attach your Saveable to your mod’s lifecycle; S1API auto-discovers subclasses.

Phone Calls

S1API lets you build scripted calls with stages and triggers, then queue them safely:

using S1API.PhoneCalls;
using UnityEngine;

public class TutorialCall : PhoneCallDefinition
{
    protected TutorialCall() : base("Guide Bot") { }

    public static void Enqueue()
    {
        var call = new TutorialCall();
        var stage = call.AddStage("Welcome to S1API!");
        stage.AddSystemTrigger(S1API.PhoneCalls.Constants.SystemTriggerType.StartTrigger);
        CallManager.QueueCall(call);
    }
}

Next steps

  • Browse the API reference in the left sidebar
  • See the Phone App and UI pages for deeper guides
  • Explore examples of existing mods using S1API
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