moveByOffset method
- double offset
Move forward or backward by a number of elements determined
by pixel offset
.
If offset
is negative, move backward; otherwise move forward.
Returns true and updates current if successful.
Implementation
bool moveByOffset(double offset) {
final Offset initialOffset = _currentOffset;
if (offset >= 0.0) {
while (_currentOffset.dy < initialOffset.dy + offset) {
if (!moveNext()) {
break;
}
}
} else {
while (_currentOffset.dy > initialOffset.dy + offset) {
if (!movePrevious()) {
break;
}
}
}
return initialOffset != _currentOffset;
}