Swift 4 - UIActivityViewController for Outlook

Question

I am trying to use UIActivityViewController for outlook only...I was able to get my UIActivityViewController working like so:

//Define HTML String

        var htmlString = ""

        //Add the headings to HTML String table

        htmlString += "<table border = '1' cellspacing='0' align = 'center'><tr><th>Job #</th><th>Task</th><th>Date</th></tr>"

        //For each item in punch list data array

        for i in 0..<punchListData.count {

            //If the item is selected

            if punchListData[i].cellSelected {

                //Add data to the HTML String

                htmlString += "<tr><td>" + jobList[i % jobList.count] + "</td><td align = 'center'>" + taskData[i / jobList.count] + "</td><td>" + (punchListData[i].stringData)! + "</td></tr>"
            }
        }

        //Close the HTML table in the HTML String

        htmlString += "</table><h5>Please contact me if you have any questions <br /> Thank you.</h5>"

        let activityViewController = UIActivityViewController(activityItems : [htmlString], applicationActivities: nil)

        activityViewController.setValue("Schedule for Community", forKey: "Subject")

        activityViewController.popoverPresentationController?.barButtonItem = self.shareButton

        self.present(activityViewController, animated: true, completion: nil)

But I have a few issues:

1. The subject line is not working, I did some research and apparently setValue will not work for Outlook and that the first line can be the subject line, but I have no idea how to do that.

2. Is there away to exclude all activities except for Outlook?

3. Previously I was just using MFMailComposeViewController to compose an email, is there away of doing this for Outlook? Without UIActivityViewController?

Thanks,

Answer 1

You can build your own UI and present it as you like, then convert arguments to a deeplink URL and pass it to the outlook app:

// MARK: - Errors
enum MailComposeError: Error {
    case emptySubject
    case emptyBody
    case unexpectedError
}

// MARK: - Helper function
func outlookDeepLink(subject: String, body: String, recipients: [String]) throws -> URL {
    guard !subject.isEmpty else { throw MailComposeError.emptySubject }
    guard !body.isEmpty else { throw MailComposeError.emptyBody }
    
    let emailTo = recipients.joined(separator: ";")
    
    var components = URLComponents()
    components.scheme = "ms-outlook"
    components.host = "compose"
    components.queryItems = [
        URLQueryItem(name: "to", value: emailTo),
        URLQueryItem(name: "subject", value: subject),
        URLQueryItem(name: "body", value: body),
    ]
    
    guard let deepURL = components.url else { throw MailComposeError.unexpectedError }
    return deepURL
}

Usage

try! UIApplication.shared.open(
    outlookDeepLink(
        subject: "subject",
        body: "body",
        recipients: ["example@email.com", "example2@email.com"]
    )
)

At last, Note that:

1. Don't forget to tell iOS you are going to call ms-outlook . (Add it to LSApplicationQueriesSchemes in info.plist , Otherwise, You will get an clear error message in console if you forget it)

2. Also don't forget to check if the app actually exists before trying to open the url. ( canOpenURL is here to help)