Objective-C is a high-level, object-oriented programming language that is primarily used for developing applications on Apple's platforms, such as iOS, macOS, watchOS, and tvOS. It is a superset of the C programming language and adds object-oriented capabilities and dynamic runtime features. Objective-C was the primary language used for iOS and macOS development before the introduction of Swift.
Objective-C syntax is based on Smalltalk, another object-oriented language. It uses square brackets to send messages to objects and follows a syntax similar to C for control flow and variable declarations. Here is an example of a simple Objective-C class:
#import <Foundation/Foundation.h>
@interface Person : NSObject
@property NSString *name;
- (void)introduce;
@end
@implementation Person
- (void)introduce {
NSLog(@"Hello, my name is %@", self.name);
}
@end
int main() {
Person *person = [[Person alloc] init];
person.name = @"Alice";
[person introduce];
return 0;
}
Developers can write Objective-C code using Apple's Xcode IDE, which provides a full suite of tools for building, testing, and debugging applications. Xcode includes a code editor, interface builder, and performance analysis tools. Objective-C code is typically compiled using the Clang compiler, which is included with Xcode. The resulting binary can then be run on Apple's platforms using the iOS Simulator or by deploying it to a physical device for testing.