setInt8 method
Sets the byte at the specified byteOffset in this object to the
two's complement binary representation of the specified value, which
must fit in a single byte.
In other words, value must be between -128 and 127, inclusive.
Throws RangeError if byteOffset is negative, or
greater than or equal to the length of this object.
Implementation
void setInt8(int byteOffset, int value);