Open Mastodon URL iOS SwiftUI

README.md

For my app, Love Your Music, I want a link to my mastodon, https://social.coop/@eb (wink wink).

On iOS, only one app can handle each URL scheme, so it's hard to know what app to open. Lets chain the apps together. Unfortunately, this means the user cannot select the default preference. To compensate, we first try the Opener app, then chain to ivory, ice cubes, then mastodon's official app, ending at the browser.

The SwiftUI open link chain is not needed for email as users can set their default mail app.

MastodonLinker.swift

struct MastodonLinker {
    var instance: String
    var user: String
    @Environment(\.openURL) private var openURL
    
    func openMastodonLink() {
        let urls = [
            "opener://x-callback-url/show-options?url=https%3A%2F%2F\(instance)%2F\(user)",
            "ivory://\(instance)/@\(user)",
            "icecubesapp://\(instance)/@\(user)",
            "mastodon://profile/\(user)@\(instance)",
            "https://\(instance)/@\(user)",
        ]
        openURLs(urls)
    }
    
    private func openURLs(_ urls: [String]) {
        guard let url = URL(string: urls.first ?? "") else {
            return
        }
        openURL(url) { canOpen in
            if !canOpen {
                let remainingURLs = Array(urls.dropFirst())
                if !remainingURLs.isEmpty {
                    self.openURLs(remainingURLs)
                }
            }
        }
    }
}

#Preview {
    List {
        Button {
            MastodonHandler(instance: "social.coop", user: "eb").openMastodonLink()
        } label:  {
            Label("Follow my Mastodon", systemImage: "pawprint")
        }.foregroundStyle(Color(hex: "6364FF").gradient)
        Button {
            if MFMailComposeViewController.canSendMail() {
                isShowingMailView.toggle()
            } else {
                openURL(URL(string: "mailto:evan (you know what goes here) boehs.org")!)
            }
        } label: {
            Label("Contact me", systemImage: "at")
        }.foregroundStyle(.green.gradient)
    }
}