How to remove language change key button from keyboard in iOS Swift 3
You cannot remove a specific button from the keyboard unless you create a custom keyboard. There are third party custom keyboards available that you can use in your application. You can also control the behavior of custom keyboards.
Another alternative is to set the keyboard type to ASCII Capable.
You can also program the keyboard type:
Swift 4:
yourTextField.keyboardType = .asciiCapable
Swift 3:
yourTextField.keyboardType = UIKeyboardType.asciiCapable
Objective C
yourTextField.keyboardType = UIKeyboardTypeASCIICapable
:;
yourTextField.keyboardType = UIKeyboardTypeNumbersAndPunctuation
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