Changes

==Dependencies==

==Dependencies==

You can define dependencies in your <tt>manifest.json</tt> file, which are other mods that must be loaded before yours. If the dependency is required and missing, SMAPI will show a friendly error to the player. See [[../Manifest|the manifest page]] for more info.

You can define dependencies in your <samp>manifest.json</samp> file, which are other mods that must be loaded before yours. If the dependency is required and missing, SMAPI will show a friendly error to the player. See [[../Manifest|the manifest page]] for more info.

==Mod registry==

==Mod registry==

Your mod can get information about loaded mods, or check if a particular mod is loaded. (All mods are loaded by the time your mod's <tt>Entry(…)</tt> method is called.)

Your mod can get information about loaded mods, or check if a particular mod is loaded. (All mods are loaded by the time your mod's <samp>Entry(…)</samp> method is called.)

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(You can use a [https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/classes-and-structs/constructors constructor] to initialise the API if desired.)</li>

(You can use a [https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/classes-and-structs/constructors constructor] to initialise the API if desired.)</li>

<li>Override <tt>GetApi</tt> in your mod's entry class and return an instance of your API:

<li>Override <samp>GetApi</samp> in your mod's entry class and return an instance of your API:

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   public override object GetApi()

   public override object GetApi()

Notes:

Notes:

* <tt>GetApi</tt> is always called after <tt>Entry</tt>, so it's safe to pass in your mod's initialised fields.

* <samp>GetApi</samp> is always called after <samp>Entry</samp>, so it's safe to pass in your mod's initialised fields.

* Be careful when changing your API! If you make a breaking change, other mods may need an update before they can access your API again.

* Be careful when changing your API! If you make a breaking change, other mods may need an update before they can access your API again.

* You can optionally add a public [https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/interface interface] to your API. If a mod directly references your mod DLL, they'll be able to use your interface instead of creating their own.

* You can optionally add a public [https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/interface interface] to your API. If a mod directly references your mod DLL, they'll be able to use your interface instead of creating their own.

}

}

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<li>In your mod code (after <tt>Entry</tt>), you can get the API by specifying the interface you created in step 1, and the [[../Manifest#Basic fields|mod's unique ID]]:

<li>In your mod code (after <samp>Entry</samp>), you can get the API by specifying the interface you created in step 1, and the [[../Manifest#Basic fields|mod's unique ID]]:

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ISomeModApi api = helper.ModRegistry.GetApi<ISomeModApi>("other-mod-ID");

ISomeModApi api = helper.ModRegistry.GetApi<ISomeModApi>("other-mod-ID");

Notes:

Notes:

* You can't call <tt>GetApi</tt> until all mods are initialised and their <tt>Entry</tt> methods called. You can use the <tt>GameLoop.GameLaunched</tt> [[#Events|event]] if you need to access mod APIs early; this is guaranteed to happen after all mods are initialised.

* You can't call <samp>GetApi</samp> until all mods are initialised and their <samp>Entry</samp> methods called. You can use the <samp>GameLoop.GameLaunched</samp> [[#Events|event]] if you need to access mod APIs early; this is guaranteed to happen after all mods are initialised.

* You should always null-check APIs you consume. <tt>GetApi</tt> will return <tt>null</tt> if the API isn't available (e.g. because the mod isn't already installed or doesn't have one), or if an error occurs fetching the API.

* You should always null-check APIs you consume. <samp>GetApi</samp> will return <samp>null</samp> if the API isn't available (e.g. because the mod isn't already installed or doesn't have one), or if an error occurs fetching the API.

===Known limitations===

===Known limitations===

* When providing an API, the interface and implementation must be public.

* When providing an API, the interface and implementation must be public.

* When mapping an API to a custom interface using <tt>GetApi&lt;T&gt;</tt> (i.e. not using the mod's original interface), only the API interface itself can be proxied. Method return values and parameters must be types that both mods have access to (e.g. built-in types like <tt>bool</tt>, SMAPI types like <tt>IManifest</tt>, or game types like <tt>GameLocation</tt>).

* When mapping an API to a custom interface using <samp>GetApi&lt;T&gt;</samp> (i.e. not using the mod's original interface), only the API interface itself can be proxied. Method return values and parameters must be types that both mods have access to (e.g. built-in types like <samp>bool</samp>, SMAPI types like <samp>IManifest</samp>, or game types like <samp>GameLocation</samp>).

==Message sending==

==Message sending==