Coding With Your Hands Tied

This session goes through the nuances on how Android libraries have to be developed in a restricted environment as they run inside other apps.

For example, while a majority of the apps use famous libraries like Retrofit or Volley to do their network calls, an SDK needs to either use AsyncTask or conjure up a trick using Threads and Handlers to ensure their networking is smooth. While apps use advanced DB libraries or frameworks like Room/Realm/greenDAO, Android libraries who cannot use these because it would mean that the apps into which they land up in would also have to add them as a dependency, have to make do with SQLite.

Once I mention the different types of problems faced by Libraries in terms of networking, database handling, UI components, handling images/GIFs/Video, efficient library size and also handling backward compatibility, I will provide my solutions which I have used in the CleverTap Android SDK as one of the possible solutions. I will also shed some light on the process of publishing libraries on JCenter or MavenCentral.

The aim of this session is to bring a wide range of app developers to the not so bright side of the development of Android Libraries and Frameworks and probably engage their minds into thinking the challenges faced by libraries and providing tried and tested solutions so that they can explore this niche world on their own.

Transcript

1. Darshan Pania CleverTap @i_m_Pania Coding With Your Hands Tied - A session on Android Library Development
2. Introduction
3. About Me Lead Android SDK Developer CleverTap https://github.com/CleverTap/clevertap-android-sdk Twitter - @i_m_Pania Darshan Pania
4. Helping marketing, product and growth teams at B2C companies retain their users for life. We enable this at scale, in real-time and with precision by providing a unique combination of: 1. A unified user data platform 2. Actionable insights and segmentation 3. Timely, personalized omni-channel engagement What does do?
5. What to expect from this session? • Interactive
6. What to expect from this session? • Interactive • Informative
7. What to expect from this session? • Interactive • Informative • Educative
8. Apps vs Libraries APP LIBRARY What is the difference?
9. Dependencies used by Apps • Networking ◦ Volley ◦ Retrofit • Image/GIFs ◦ Glide ◦ Picasso • Video ◦ ExoPlayer • Databases ◦ Room ◦ Realm ◦ greenDAO • Dependency Injection ◦ Dagger ◦ ButterKnife • UI Components ◦ Constraint Layout
10. This is how an App’s build.gradle file looks like -
11. Dependencies used by Libraries • Networking ◦ None • Image/GIFs ◦ None • Video ◦ None • Databases ◦ None • Dependency Injection ◦ None • UI Components ◦ None
12. Dependencies used by CleverTap SDK • Networking ◦ None • Image/GIFs ◦ Glide • Video ◦ ExoPlayer • Databases ◦ None • Dependency Injection ◦ None • UI Components ◦ None
13. This is how CleverTap SDK’s build.gradle file looks like -
14. Solutions for Libraries
15. How do Libraries handle Networking? • HTTPS Connection • A custom queueing mechanism
16. Setting up HTTPS connections
17. Setting up a queueing mechanism
18. How do Libraries handle Images/GIFs/Videos? • LRUCache • ExoPlayer is the best!
19. Initializing a LRUCache
20. Adding a Bitmap or GIF byte array data to the LRUCache
21. Using ExoPlayer to stream videos
22. Part I - Prepare the media to be shown
23. Part II - Play the media
24. How do Libraries handle Databases? • SQLite
25. Creating Tables, handling Database initialization and Database upgrade
26. How do Libraries handle Dependency Injection? • Good old findViewById
27. A simple XML Layout
28. Handling UI views in code
29. How do Libraries handle UI layouts? • Legacy is the only way for us...
30. XML Layout for our Inbox Activity
31. What can we do better?
32. How to publish Libraries? • Setup Bintray account • Setup your build.gradle • Package and Publish
33. Setup a Bintray Account
34. Bintray is your friend!
35. Add a New Repository!
36. Give your repository a name, select “Maven” as a type
37. Click the “Add New Package” button, fill in the data
38. Setup your build.gradle
39. Add your Bintray username and API key to local.properties In the build.gradle of your library module
40. implementation ‘com.darshan.logg:logg:1.0’
41. At the end of your build.gradle file, you need to add this
42. Package and Publish
43. Now run two Gradle commands on your Terminal/Android Studio
44. Add your library to JCenter
45. Q&A That’s all folks!
46. Darshan Pania, CleverTap @i_m_Pania Thank you!