# BuildPipeline

> Provides iOS build pipeline events that let you supply resources and on-demand resource tags to the Xcode asset catalog during a build.

## Definition

* **Type:** Class
* **Namespace:** [UnityEditor.iOS](/engine/6000.6/script-reference/unityeditor/ios.md)
* **Assembly:** UnityEditor.Apple.Extensions.Common

```csharp
public static class BuildPipeline
```

## Remarks

Subscribe to `collectResources` to register [Resource](/engine/6000.6/script-reference/unityeditor/ios/resource.md) objects that Unity writes into the generated `UnityData.xcassets` catalog. Subscribe to `collectInitialInstallTags` to mark on-demand resource tags for prefetch during initial app installation. Register subscriptions before the build runs, for example in a method decorated with `[InitializeOnLoadMethod]`.

Additional Resources: [Resource](/engine/6000.6/script-reference/unityeditor/ios/resource.md), [\_collectInitialInstallTags](/engine/6000.6/script-reference/unityeditor/ios/buildpipeline/collectinitialinstalltags.md).

## Static Events

| Member                                                                                                                  | Description                                                                                   |
| ----------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------- |
| [collectInitialInstallTags](/engine/6000.6/script-reference/unityeditor/ios/buildpipeline/collectinitialinstalltags.md) | Raised when the build pipeline collects on-demand resource tags for initial app installation. |
| [collectResources](/engine/6000.6/script-reference/unityeditor/ios/buildpipeline/collectresources.md)                   | Raised when the build pipeline collects resources to add to the Xcode asset catalog.          |

## Delegates

| Delegate                                                                                                                                      | Description                                                                               |
| --------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------- |
| [BuildPipeline.OnDemandTagsCollectorDelegate](/engine/6000.6/script-reference/unityeditor/ios/buildpipeline/ondemandtagscollectordelegate.md) | Delegate function for supplying on-demand resource tag strings to the iOS build pipeline. |
| [BuildPipeline.ResourcesCollectorDelegate](/engine/6000.6/script-reference/unityeditor/ios/buildpipeline/resourcescollectordelegate.md)       | Delegate function for supplying Resource objects to the iOS build pipeline.               |