Share Extension

SHARE EXTENSION: SETUP: Requires separate extension target (kind: "share" in plan extensions array). The extension receives shared content (URLs, text, images) from other apps via the share sheet.

PRINCIPAL CLASS (in extension target): class ShareViewController: SLComposeServiceViewController { override func isContentValid() -> Bool { return contentText.count > 0 // Validate before enabling Post button }

override func didSelectPost() {
    // Access shared items
    guard let item = extensionContext?.inputItems.first as? NSExtensionItem,
          let provider = item.attachments?.first else {
        extensionContext?.completeRequest(returningItems: [], completionHandler: nil)
        return
    }

    if provider.hasItemConformingToTypeIdentifier("public.url") {
        provider.loadItem(forTypeIdentifier: "public.url") { [weak self] url, _ in
            // Handle URL
            self?.extensionContext?.completeRequest(returningItems: [], completionHandler: nil)
        }
    }
}

override func configurationItems() -> [Any]! {
    return []    // Return SLComposeSheetConfigurationItem array for optional UI
}

}

INFO.PLIST KEYS (in extension's Info.plist via XcodeGen): NSExtensionPrincipalClass: $(PRODUCT_MODULE_NAME).ShareViewController NSExtensionActivationRule: NSExtensionActivationSupportsWebURLWithMaxCount: 1 NSExtensionActivationSupportsText: true

APP GROUP: Use AppGroup entitlement to share data between main app and extension.