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Enable Disable Mod Functionality

Description​

The Component UI includes support for enabling and disabling mods in your UI and game. Note that persistence of this data is up to developers to implement. You could do this via the Unreal Engine save game system, for instance.

Enable the feature flag​

Enable/Disable is behind a feature flag under Project Settings > Plugins > mod.io > Feature Flags > Enable Mod Enable/Disable support. Enabling this is the first step to using the built-in feature.

Adding an IModEnabledStateProvider​

Just like the rest of the Component UI, the Enable/Disable functionality is driven by an interface: IModEnabledStateProvider. The class on which you implement this interface will be a data provider for the state of mods, and will also receive callbacks for enable and disable events that are triggered from the components. You can also implement this interface in Blueprint. Generally speaking, something that persists for a long time such as a GameInstance or your UGC Manager Subsystem should implement this interface and handle persistence.

Registering the IModEnabledStateProvider​

Whichever class implements IModEnabledStateProvider has to register itself with the UI Subsystem as follows:

if (UModioUISubsystem* UISubsystem = GEngine->GetEngineSubsystem<UModioUISubsystem>())
{
    UISubsystem->SetModEnabledStateDataProvider(this);
}

Handling a state change​

When you enable or disable a mod from the UI, the IModEnabledStateProvider will receive a RequestModEnabledStateChange callback. You can then store the state of the ModID. As an example, if you were just storing this per-session, your implementing class could declare something such as TSet<int64> DisabledMods and update it like so:

bool UModioGameInstance::NativeRequestModEnabledStateChange(int64 ID, bool bNewEnabledState)
{
    if (bNewEnabledState)
    {
        DisabledMods.Remove(ID);
    }
    else
    {
        DisabledMods.Add(ID);
    }
    return true;
}

Querying the state of a mod​

Similarly, whenever the Enable/Disable state of a mod needs to be queried by the UI, the IModEnabledStateProvider will receive a QueryIsModEnabled callback which simply returns whether the mod is enabled or not:

bool UModioGameInstance::NativeQueryIsModEnabled(int64 ModID)
{
    return !DisabledMods.Contains(ModID);
}

Note that QueryUserInstallations will still return all mods regardless of whether they are enabled or disabled. When it comes to loading and unloading content, you should query your own storage of this data to decide whether to load or unload content.