Xcode Read and Process Scheme Run Arguments

This tutorial demonstrates how to read and process command-line arguments passed to an iOS app through the Xcode scheme.

1. Create a new Swift project in Xcode.
2. Open the main.swift file and replace the existing code with the following code:

swiftCopy codeimport Foundation

// To view the arguments, you can
let arguments = ProcessInfo.processInfo.arguments

for any in arguments {
    print(any)
}

// To view a specific argument
let customKeyIndex = arguments.firstIndex(of: "-customKey")

// -> Set the app's environment to development, staging, or production, which could impact API endpoints, logging levels, or other settings
// -environment development

// -> Feature Flags
// -enableExperimentalFeature true

// -> Logging
// -verboseLogging true

// -> Preload test data or use actual data
// -preloadTestData true

3. Now, let’s add some custom launch arguments to the Xcode scheme. In the top navigation bar, click on the active scheme (next to the Run and Stop buttons).
4. Select “Edit Scheme…” from the dropdown menu.
5. In the scheme editor, select the “Run” action in the left sidebar.
6. Switch to the “Arguments” tab in the right pane.
7. Under the “Arguments Passed On Launch” section, click the “+” button to add a new launch argument.
8. Add some custom arguments like -customKey customValue, -environment development, -enableExperimentalFeature true, -verboseLogging true, and -preloadTestData true. Click “Close” to save the changes.
9. Run the app by clicking the Run button or pressing Cmd + R. The app will print the launch arguments in the console.
10. To process these arguments, you can add code to the main.swift file. For example, you can process the -environment argument like this:

swiftCopy codeif let environmentIndex = arguments.firstIndex(of: "-environment"), environmentIndex + 1 < arguments.count {
    let environmentValue = arguments[environmentIndex + 1]
    print("Environment: \(environmentValue)")
} else {
    print("No environment value found")
}

This code snippet searches for the -environment argument and prints its value if found. You can follow a similar approach to process the other custom arguments.

That’s it! This tutorial demonstrates how to read and process command-line arguments in an iOS app using Swift. You can use this approach to pass configuration values, enable or disable features, control logging, or preload test data.