title: What method gets executed when the application resumes from the background
body: <p>I need to know the method that gets executed when;</p>
  
  <p>1.) the application resumes from the background (if we send the application to the background, and later when we resume the application from background)</p>
  
  <p>2.) while using the application, the screen gets locked, and then we have to slide the lock screen slider to get in to the app. What is the method executed then.</p>