Implementing a Vertical TextView from Scratch and Related Techniques

on YouTube ↗50m

" summary

A hands-on Android implementation of a vertical (vertical-writing) TextView built from View, InputConnection, Editable and Bitmap is presented, showing that text input can be implemented without using TextView or String. The talk covers how TextView and IME work, pitfalls of InputConnection, how strings and fonts produce bitmaps (including OpenType and Unicode/emoji issues), cross-platform vertical TextView experience, recent Android font changes like Variable Fonts, and practical cautions for implementing vertical text.

AI-written summary · about

" chapters (8)

1. 0:00Vertical TextView intro
2. 6:16TextView display basics
3. 15:10Text to rendered images
4. 23:33Vertical writing specifics
5. 33:38Text editing and IME
6. 42:49Custom IME API
7. 44:17TextView optimizations
8. 49:02Vertical text challenges

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