How to Create a Universal Framework for iOS

How create a Framework for iOS using Swift. Based on a mix of Elad Nava and Zaid Pathan posts. Modified and updated to work with XCode 9. Include a example project.

1. Create a Project

Create a new Xcode project for your framework and select the Cocoa Touch Framework template:

Enter a Product Name and choose Swift as the project language. For the purpose of writing this guide, I've chosen to create a framework called JJMRSDK that exposes a method which simply prints a String to the console.

Feel free to replace this dummy implementation with your own functionality, and replace JJMRSDK with your own framework name whenever mentioned in the rest of this guide.

2. Create framework for both iOS Device and Simulator add new Aggregate target to your project.

Add a new target:

File > New > Target...

Add Agregate target called JJMRSDK-Universal

In Build phases add New Run Script Phases

Paste the following script

#!/bin/sh
UNIVERSAL_OUTPUTFOLDER=${BUILD_DIR}/${CONFIGURATION}-universal
# make sure the output directory exists
mkdir -p "${UNIVERSAL_OUTPUTFOLDER}"
# Step 1. Build Device and Simulator versions
xcodebuild -target "${PROJECT_NAME}" ONLY_ACTIVE_ARCH=NO -configuration ${CONFIGURATION} -sdk iphoneos  BUILD_DIR="${BUILD_DIR}" BUILD_ROOT="${BUILD_ROOT}" clean build
xcodebuild -target "${PROJECT_NAME}" -configuration ${CONFIGURATION} -sdk iphonesimulator ONLY_ACTIVE_ARCH=NO BUILD_DIR="${BUILD_DIR}" BUILD_ROOT="${BUILD_ROOT}" clean build
# Step 2. Copy the framework structure (from iphoneos build) to the universal folder
cp -R "${BUILD_DIR}/${CONFIGURATION}-iphoneos/${PROJECT_NAME}.framework" "${UNIVERSAL_OUTPUTFOLDER}/"
# Step 3. Copy Swift modules from iphonesimulator build (if it exists) to the copied framework directory
SIMULATOR_SWIFT_MODULES_DIR="${BUILD_DIR}/${CONFIGURATION}-iphonesimulator/${PROJECT_NAME}.framework/Modules/${PROJECT_NAME}.swiftmodule/."
if [ -d "${SIMULATOR_SWIFT_MODULES_DIR}" ]; then
cp -R "${SIMULATOR_SWIFT_MODULES_DIR}" "${UNIVERSAL_OUTPUTFOLDER}/${PROJECT_NAME}.framework/Modules/${PROJECT_NAME}.swiftmodule"
fi
# Step 4. Create universal binary file using lipo and place the combined executable in the copied framework directory
lipo -create -output "${UNIVERSAL_OUTPUTFOLDER}/${PROJECT_NAME}.framework/${PROJECT_NAME}" "${BUILD_DIR}/${CONFIGURATION}-iphonesimulator/${PROJECT_NAME}.framework/${PROJECT_NAME}" "${BUILD_DIR}/${CONFIGURATION}-iphoneos/${PROJECT_NAME}.framework/${PROJECT_NAME}"
# Step 5. Convenience step to copy the framework to the project's directory
cp -R "${UNIVERSAL_OUTPUTFOLDER}/${PROJECT_NAME}.framework" "${PROJECT_DIR}"
# Step 6. Convenience step to open the project's directory in Finder
open "${UNIVERSAL_OUTPUTFOLDER}"

3. Build your first framework by Choosing JJMRSDK-Universal target pressing ⌘ + B

After build completed,You will see Finder opening with Your Framework in that.

This is your Universal Framework you can import now in a separate project.

4. Test on Terminal

Verify that JJMRSDK.framework is indeed a universal framework by running file JJMRSDK directory: Open The Terminal and type

file JJMRSDK.framework/JJMRSDK 

The file contains binaries for the x86_64 and arm64 architectures, which makes it a universal-

5. Create a Demo Project

Create demo target with Single View Application called JJMRSDK-Demo for example

When the demo target is created, navigate to its project editor, scroll down to the Embedded Binaries section, click the + icon, and select JJMRSDK.framework:

6. Test thats works

Create a simple Class and write some code:

import UIKit

open class JJMRSDK: NSObject {
    public static let shared = JJMRSDK()
    
    open func hello(){
        debugPrint("Hello World!")
    }
}

Import the library in any project and test:

import UIKit
import JJMRSDK

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        JJMRSDK.shared.hello()
        // Do any additional setup after loading the view, typically from a nib.
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }


}

7. Build universal framework for Carthage

Select your Universal Target, go to Build Settings and set these values:

Add a new User-Defined Setting:

And set a new value like this:

Make Build, Archive, upload to your repository and enjoy your new framework!