My simple understanding of XCode Objective-c Cocoa, xcodeobjective-c

My simple understanding of XCode Objective-c Cocoa, xcodeobjective-c
My brief understanding of XCode Objective-c Cocoa Xcode

Xcode is generally used to develop OS X and iOS applications.

If we want to be serious, Xcode is an integrated development tool (IDE) running on Mac OS X, developed by Apple. Xcode has a unified user interface design. coding, testing, and debugging are all completed in a simple window.

For an iOS developer, Xcode is a software that I learned from the first day of OC learning. In my opinion, he is very powerful. Why does he say this? As Xcode is updated, it is more and more convenient to use.

Below are some shortcut keys for Xocde to help save development time.

File
CMD + N: New File
CMD + SHIFT + N new project
CMD + O: Open
CMD + S: Save; CMD + SHIFT + S: Save
CMD + W: Close the window
CMD + SHIFT + W: Close the file
Edit
CMD + [: Left indent; CMD +]: Right indent
CMD + CTRL + LEFT: Fold
CMD + CTRL + RIGHT: unhide
CMD + CTRL + TOP: collapse all functions
CMD + CTRL + BOTTOM: cancel all function folding
CTRL + U: cancel all collapse
CMD + D: Add bookmarks
CMD +/: comment or cancel the comment
CTRL +.: parameter prompt
ESC: Automatic prompt list
Debugging
CMD +: set or cancel a breakpoint
CMD + OPT +: Allows or disables the current breakpoint
CMD + OPT + B: View All Breakpoints
CMD + RETURN: Compile and run (determine whether to enable breakpoint Based on settings)
CMD + R: Compile and run (do not trigger breakpoint)
CMD + Y: Compile and debug (trigger breakpoint)
CMD + SHIFT + RETURN: stops running or debugging
CMD + B: Compile
CMD + SHIFT + K: Clear

Objective-c

Objective-C is a tool for compiling the following applications:

• IOS operating system
• IOS Application
• Mac OS X operating system
• Applications on Mac OSX

The popularity of Objective-C is attributed to the success of the iPhone. The main programming language for writing iPhone applications is Objective-C.

OC is a very small Runtime Library written in C. It is fully compatible with standard c language (hyperset of C ). OC does not support multiple inheritance.
OC is dynamic.

Cocoa

Cocoa is a native object-oriented API created by Apple for Mac OS x. It is one of the five major APIs on Mac OS X (the other four are Carbon, POSIX, X11, and Java ).
Cocoa evolved from the programming environment NeXTSTEP and OPENSTEP developed by NeXT in the 1980 s.
Cocoa design follows strict MVC principles.
In most object-oriented programming languages, calling methods are implemented by directly calling a fixed piece of code in the memory. This method requires a predefined class for processing commands, which limits the program design. Generally, the responsibility chain mode is used as the design mode. Although Cocoa still adopts this method in most places, the dynamic binding feature of Objective-C adds more design freedom, KVC/KVO.
A feature of the Cocoa environment is that it can manage dynamically allocated memory.