This change brings iOS return key behaviour in line with current behaviour on
Android.
* Implements TextInputClient.performAction for iOS Adds FlutterTextInputAction
* enum Defaults return key to 'Done' Ends editing and hides the keyboard if
* 'Done' is pressed
Future work is planned to support configurable return/action key behaviour.
See: #9573, #9210, #8028.
Previously, it was a static. Doesn't have much effect in practice because we
only use this microtask queue for main isolates, which exist on a single
thread.
Ensure that both self.text and self.selectedTextRange are updated before
triggering textDidChange: or selectionDidChange: on the input delegate
(which then re-computes positions). This prevents inconsistencies in
selection vs text position/offset lookups triggered by didChange
notifications.
Ensure that rangeOfComposedCharacterSequenceAtIndex: is only ever called
for index values > 0 && < self.text.length. This prevents such calls for
position with index == self.text.length.
Also reduces unnecessary textDidChange/selectionDidChange notifications:
replaceRange:withText: and setMarkedText:selectedRange: are only ever
called by UIKit and methods called by UIKit (insertText,
deleteBackward), so notification is unnecessary.
textContentType was added in iOS 10, and we target iOS 8. Either way the
framework doesn't (yet) include support for this; keyboard type covers
most bases.
Supports:
* autocorrect, suggestions view/selection.
* Support for Chinese, Japanese, Korean and other languages using
multi-stage input with candidate selection.
* styling the composing (mark) region for multi-stage input
* key-repeat when backspace held down
* physical and soft keyboard support for arrow key cursor movement and
selection.
* improved third-party keyboard support
Does not yet support:
* force-touch drag cursor positioning
* auto-positioning the candidates view for multi-stage input methods
when used with a physical keyboard (e.g., iPad Pro) currently
positioned at 0,0.
* voice dictation
Ensure selection base is updated when deleting surrogates
This fixes a bug in which the selection base was not updated when
deleting at index of the trailing char of a Unicode surrogate,
introduced in 38664ac32223228476166b9050ab400c102fda05.
Minor refactor to consolidate logic around NSRange.
* Maintain FlutterTextInputView text in NSMutableString
We were converting from/to NSString at the interface of
FlutterTextInputView; instead use NSMutableString to maintain the
internal buffer.
Eliminates nsstring_utils.{h,mm} which no longer has any users.
