UIInputViewController
In viewDidLoad method, set a custom height.
Printed log display height is already customized(in viewDidLoad and viewWillAppear)
But
in viewDidAppear, the system reset it to default: 215 .
When the keyboard pops up, the height reset animation causes the page to flash.(Height changed more than once)
Under the same system version, there's this problem on the iPhone 6 ,there is no problem on the iPhone X. Other devices have not been tested.
