Unity UI InputField can't type Chinese in iOS by speed dial type keyboard

Questions & Answers
1
  1. Create an UI Inputfield component, and choose the linetype to Singleline
  2. Build the game and install it to an iOS device (ex. iPhone)
  3. Set the iOS keyboard to Speed Dial type (9 buttons type) and use Chinese pinyin input
  4. Open the game, you cannot type Chinese characters into the inputfield.

But the other two line type or other kind of keyboard(ex. full keyboard) works fine.
Anyone can tell me why?
Thank you!

unity version: 5.3.4f1

2

Same issue founded in 5.3.4p1. Do you find a solution?