In-App Routing

import UIKit
import BranchSDK // Assuming Branch SDK is imported

class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {

        // Initialize the session, setup a deep link handler
        Branch.getInstance().initSession(launchOptions: launchOptions) { (params: [AnyHashable: Any]?, error: Error?) in
            // Start setting up the view controller hierarchy
            guard let navC = self.window?.rootViewController as? UINavigationController else {
                // Handle the case where the rootViewController is not a UINavigationController,
                // or self.window is nil. This might involve logging an error or
                // taking alternative setup steps.
                print("Error: Root view controller is not a UINavigationController or window is nil.")
                return
            }

            let storyboard = UIStoryboard(name: "Main", bundle: nil)
            var nextVC: UIViewController

            // If the key 'pictureId' is present in the deep link dictionary
            // then load the picture screen with the appropriate picture
            if let pictureId = params?["pictureId"] as? String {
                // Assuming "PicVC" has a custom class PicViewController
                // and it has a method setNextPictureId or a property to set the pictureId.
                // If it's a method:
                if let picViewController = storyboard.instantiateViewController(withIdentifier: "PicVC") as? PicViewController {
                    picViewController.setNextPictureId(pictureId) // Assuming PicViewController has this method
                    nextVC = picViewController
                } else {
                    // Fallback if PicVC can't be instantiated or cast
                    print("Error: Could not instantiate PicViewController with identifier 'PicVC'. Falling back to MainVC.")
                    nextVC = storyboard.instantiateViewController(withIdentifier: "MainVC")
                }
                // Alternatively, if PicViewController has a property:
                // if let picViewController = storyboard.instantiateViewController(withIdentifier: "PicVC") as? PicViewController {
                //     picViewController.nextPictureId = pictureId // Assuming PicViewController has this property
                //     nextVC = picViewController
                // } else {
                //     print("Error: Could not instantiate PicViewController with identifier 'PicVC'. Falling back to MainVC.")
                //     nextVC = storyboard.instantiateViewController(withIdentifier: "MainVC")
                // }

            } else {
                nextVC = storyboard.instantiateViewController(withIdentifier: "MainVC")
            }

            // Navigate!
            navC.setViewControllers([nextVC], animated: true)
        }

        return true
    }
}

// Example of what PicViewController might look like:
class PicViewController: UIViewController {
    var nextPictureId: String?

    // If using a method to set the ID
    func setNextPictureId(_ id: String) {
        self.nextPictureId = id
        // Potentially load picture data here based on the ID
        print("PicViewController: pictureId set to \(id)")
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        // If the ID was set as a property, you might use it here
        if let pictureId = nextPictureId {
            print("PicViewController loaded with pictureId: \(pictureId)")
            // Load picture data
        }
    }
}

// Example of what MainViewController might look like (just for completeness):
class MainViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        print("MainViewController loaded")
    }
}

import android.content.Intent
import android.os.Bundle // Required for onStart, though not directly used in the snippet
import android.util.Log
import androidx.appcompat.app.AppCompatActivity // Assuming this is an Activity
import io.branch.referral.Branch
import io.branch.referral.BranchError
import org.json.JSONObject

// Assuming your class is an Activity, replace YourActivityName with its actual name
class YourActivityName : AppCompatActivity() { // Or androidx.fragment.app.FragmentActivity, etc.

    override fun onStart() {
        super.onStart()

        // `this` (the Activity context) is passed to sessionBuilder
        Branch.sessionBuilder(this).withCallback { referringParams: JSONObject?, error: BranchError? ->
            if (error == null) {
                // params are the deep linked params associated with the link that the user clicked before showing up
                // params will be empty if no data found

                // Use elvis operator for default value if referringParams is null
                val pictureID = referringParams?.optString("picture_id", "") ?: ""

                if (pictureID.isEmpty()) {
                    // `this@YourActivityName` explicitly refers to the Activity context
                    startActivity(Intent(this@YourActivityName, HomeActivity::class.java))
                } else {
                    val intent = Intent(this@YourActivityName, ViewerActivity::class.java)
                    intent.putExtra("picture_id", pictureID)
                    startActivity(intent)
                }
            } else {
                Log.e("MyApp", error.message)
            }
        }.withData(this.intent?.data).init() // Use safe call for intent.data as it can be null
    }
}

// Example stubs for HomeActivity and ViewerActivity for completeness
class HomeActivity : AppCompatActivity() {
    // ...
}

class ViewerActivity : AppCompatActivity() {
    // ...
}

let params = Branch.getInstance().getLatestReferringParams()

val sessionParams: JSONObject? = Branch.getInstance().getLatestReferringParams()

let params = Branch.getInstance().getFirstReferringParams()

val installParams: JSONObject? = Branch.getInstance().getFirstReferringParams()

import BranchSDK // Make sure to import the Branch SDK

let linkProperties = BranchLinkProperties()
linkProperties.feature = "sharing"
linkProperties.channel = "facebook"
linkProperties.addControlParam("$deeplink_path", withValue: "content/1234")

import io.branch.referral.util.LinkProperties // Verify this import path based on your project setup and Branch SDK version

val linkProperties = LinkProperties()
    .setChannel("facebook")
    .setFeature("sharing")
    .addControlParameter("\$deeplink_path", "content/1234") // Or simply "$deeplink_path"