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iOS

Posted by Chengyu Deng
Chengyu Deng
7,879 Points

How Xcode calls methods in view controller class when we are running the project?

I know we can write our code in the view did load method so that after the view finishes loading, our codes inside of viewDidLoad method can be executed. My question is how does Xcode know to call viewDidLoad method when the project is running? are there any specific built in codes to make Xcode running the project? I know if we run want to run project, we can simply press run button to run, but I am kinda curious about what's going behind the scene. Please help! Appreciate it!

1 Answer

Michael Hulet
Michael Hulet
47,913 Points

The viewDidLoad method is called as part of the "View Controller Lifecycle", which is a set of methods that you define that will be called automatically by iOS at key points in the life of your view controller. Other methods include viewWillAppear:, viewDidAppear:, viewWillDisappear:, viewDidDisappear:, and didRecieveMemoryWarning. These are all called automatically by iOS at certain important times during the life of your view controller

Chengyu Deng
Chengyu Deng
7,879 Points

Thanks!!