Join Scott Gardner for an in-depth discussion in this video Use final, part of Swift 3 Essential Training: Beyond the Basics.
- [Instructor] There will be times when you want…to prevent subclasses from overriding properties or methods.…To do that begin the definition with a key word final.…I have two classes, a ClassA base class…with a print greeting method,…and Class B that inherits from Class A…and overrides its print greeting method.…To prevent ClassB from being able…to override the print greeting method,…I'll write the final key word…at the beginning of the definition of ClassA.…And now the error on ClassB's print greeting…indicates that I'm trying to override a final method.…
I'll comment that out.…To prevent a class from being subclass all together,…write the final key word before the class definition.…I'll mark ClassB as final.…And now I'll define a ClassC…that attempts to subclass ClassB.…And I'll get a similar error as before,…indicating that I'm trying to inherit…from a final class this time.…I'll comment that out too.…Using final, wherever property, method, or whole class…is not going to overwritten or subclass…can also significantly improve compiler performance.…
- Adding source files, resources, links, and literals
- Adding pages to a playground
- Using overflow operators and bitwise operators
- Using ranges with strings
- Creating complex sequences
- Chaining higher-order functions
- Defining lazy properties
- Using failable initializers
- Mutating methods
- Working with singletons
- Nesting function types
- Creating error types and recursive enumerations
- Extending concrete types
- Referencing selectors and key paths
- Working with protocol-oriented programming
- Defining class-only protocols and optional protocols
- Using option sets, type checking, and casting operators
Skill Level Intermediate
Core Data for iOS and macOS Enterprise Developerswith Jon Bott1h 46m Intermediate
Distributing Your iOS App for Testing with TestFlightwith Ron Buencamino35m 10s Intermediate
iOS App Development: Test-Driven Developmentwith Harrison Ferrone2h 14m Intermediate
3. Strings and Characters
4. Sequences and Collections
5. Control Flow
6. Value and Reference Types
9. Access Control
Understand access control3m 47s
Next steps1m 2s
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