extendSelection method
Similar to setSelection, but will, if shift is held or the extending flag
is set, move the head of the selection while leaving the anchor at its
current place. to
is optional, and can be passed to ensure a region (for
example a word or paragraph) will end up selected (in addition to whatever
lies between that region and the current anchor). When multiple selections
are present, all but the primary selection will be dropped by this method.
Supports the same options as setSelection.
Implementation
void extendSelection(Position from, [Position? to, Map? options]) {
callArgs('extendSelection', [from.toProxy(), to?.toProxy(), options]);
}