Native Cross-Platform

A better way to build native apps with J2Objc, RoboVM, Xamarin or Djinni?

Transcript

1. Native Cross-Platform Wolfgang Frank | arconsis IT-Solutions GmbH A better way to build native apps?
2. Cross-Platform development? Reuse as much code & components as possible between different "mobile" platforms
3. It is hard! → Develop several native apps ("reuse concepts", mobile GW) → HTML5/JS based hybrid apps (e.g. Cordova, Appcelerator)
4. Other choices → MDSD/MDA model driven approach (e.g. iphonical, applause) → JavaScript to native bridge (e.g. Transit) → Commonly used C/C++ libraries (with NDK)
5. But, can I run Java/C# on any platform?
6. Yes, absolutely! * Transpile code: J2Objc, XMLVM * Cross-compile code: Xamarin (C#), RoboVM (Java)
8. J2Objc
9. Look at J2Objc → Transpiler: Java source code to Objc source code → Open source project from Google → Write non-UI (i.e. data access, application logic) in Java
10. J2ObjC supports "most" Java language and runtime features → exceptions → inner & anonymous classes → generic types → threads → reflection
11. https://github.com/google/j2objc
12. J2ObjC is currently in beta ... ...but used in production - like Google Drive
13. Examples $ j2objc HelloWorld.java translating HelloWorld.java Translated 1 file: 0 errors, 0 warnings => HelloWorld.m, HelloWorld.h
14. Compile translated file $ j2objcc -c HelloWorld.m Build an executable $ j2objcc -o hello HelloWorld.o $ ./hello HelloWorld hello, world
15. How to integrate in development? 1. External build 2. Xcode build rule
16. Pros & Cons
17. ! Pros → fast to get started (low learning curve) → "readable" runtime code → relatively easy to integrate and debug
18. ! Cons → need all source code → okay, but not great to read code → Objective-C in a Swift world
19. Look at some examples (demo)
20. RoboVM
21. Our mission is to bring Java to iOS and to do it properly. We empower the Java developer. — RoboVM
22. Look at RoboVM → Cross-compiler: Java bytecode to native ARM / x86 → Now closed source aquired by Xamarin/Microsoft → Build complete iOS/Android Apps using native UI’s & full hardware access → Build dynamic frameworks for iOS (NEW)
23. RoboVM features → Currently based on Android Java Runtime → Eclipse integration (Plugin) → RoboVM Studio (IntelliJ based IDE) → Create App Store ready apps → Dynamic frameworks
24. http://www.robovm.com
25. RoboVm production ready and used successfully (e.g. libGDX games, ...)
26. Eclipse plugin available in market http://download.robovm.org/eclipse/ RoboVM Studio https://robovm.com/download/
27. Examples $ <PATH_TO_ROBOVM>/bin/robovm -verbose -cp bin/ HelloWorld => *.o file created plus executable
28. Pros & Cons
29. ! Pros → "easier" for Java developers to get started with iOS → Dynamic Frameworks => best of both worlds → Nice IDE support with gradle and RoboVM studio → Great if Android & iOS are only platforms → Based on Bytecode!!! => Kotlin :)
30. ! Cons → slower build process (turnaround) → Debugging for Dynamic Frameworks missing → No Windows support → Future after Microsoft aquisition unclear → Expensive
31. Look at some examples (demo)
33. Xamarin
34. Look at Xamarin → Cross-compiler: C# to native ARM / x86 → Aquired by Microsoft → Build complete iOS/Android/Windows Apps using native UI’s & full hardware access
35. Xamarin features → Currently based on .NET/Mono → Xamarin Studio → Visual Studio (plus Build-Host for iOS) → Create App Store ready apps → "Ahead of Time" compile on iOS → Mono Runtime on Android
36. http://www.xamarin.com
37. Xamarin production ready and used successfully (e.g. LMZ/medialesson Lernraum)
38. Architecture → PCL (Portable Class Libraries) → MVVM / VIPER → Principles also apply to RoboVM
40. Pros & Cons
41. ! Pros → "easier" for C# developers to get started → Very mature → iOS + Android + Windows → powerful/modern language C# → Good documentation
42. ! Cons → slower build process (turnaround) → Xamarin Studio IDE / Visual Studio → Learning curve for non-C# developers → Expensive
43. Look at some examples (demo)
44. Djinni
45. Look at Djinni → Dropbox framework (Mailbox, Dropbox, ...) → Create native bindings to C++ (Shared code) → Objective-C++ / Android NDK → Textual DSL -> Generator
46. Features → Generates interface code -> bidirectional calls between C++ and Java (with JNI) or Objective-C (with Objective-C++)
47. Enums my_enum = enum { option1; option2; option3; }
48. Basic data structures my_record = record { id: i32; info: string; store: set<string>; hash: map<string, i32>; values: list<another_record>; # Comments can also be put here # Constants can be included const string_const: string = "Constants can be put here"; const min_value: another_record = { key1 = 0, key2 = "" }; } another_record = record { key1: i32; key2: string; } deriving (eq, ord)
49. Interfaces / Services # This interface will be implemented in C++ and can be called from any language. my_cpp_interface = interface +c { method_returning_nothing(value: i32); method_returning_some_type(key: string): another_record; static get_version(): i32; # Interfaces can also have constants const version: i32 = 1; } # This interface will be implemented in Java and ObjC and can be called from C++. my_client_interface = interface +j +o { log_string(str: string): bool; }
50. How to run src/run \ --java-out JAVA_OUTPUT_FOLDER \ --java-package com.example.jnigenpackage \ --java-cpp-exception DbxException \ # Choose between a customized C++ exception in Java and # java.lang.RuntimeException (the default). --ident-java-field mFooBar \ # Optional, this adds an "m" in front of Java field names \ --cpp-out CPP_OUTPUT_FOLDER \ \ --jni-out JNI_OUTPUT_FOLDER \ --ident-jni-class NativeFooBar \ # This adds a "Native" prefix to JNI class \ --objc-out OBJC_OUTPUT_FOLDER \ --objc-type-prefix DB \ # Apple suggests Objective-C classes have a prefix for each defined type. \ --objcpp-out OBJC_OUTPUT_FOLDER \ \ --idl MY_PROJECT.djinni
51. https://github.com/dropbox/djinni
52. Look at some examples (demo)
53. Thank you! wolfgang.frank@arconsis.com @wolfgangfrank
54. arconsis?
55. www.arconsis.com Mobile Enterprise & Adaptive Enterprise
56. arconsis - services → iOS & Android trainings (arconsis academy) → Mobile development (native + cross-platform + mobile web) → Mobile Gateway / MBaaS (Red Hat Mobile Application Platform) → Mobile strategy & mobile UX → Agile coaching (Scrum, Lean, TDD, ...)