How to launch application and bring it to front using Cocoa api?

Question

I\'m very new to a cocoa programming and I can\'t find the way to do the following:

• Start a particular application by name
• Do some work
• Later

Answer 1

For Swift2 version

Launch App:

let task = NSTask()
task.launchPath = "/usr/bin/env"
task.arguments = ["/Applications/TextEdit.app/Contents/MacOS/TextEdit"]
task.launch()

To get the app using bundle Identifier:

    var apps: [AnyObject] = NSRunningApplication.runningApplicationsWithBundleIdentifier("com.apple.TextEdit")
    var MyApp: [NSRunningApplication] = apps as! [NSRunningApplication]        
            for app in MyApp        
            {
            }

I am still trying to find the way to know "active", "hide" etc state of app, But not succeed till now.