restoreOffset method
Called by context to restore the scroll offset to the provided value.
The provided value has previously been provided to the context by calling ScrollContext.saveOffset, e.g. from saveOffset.
This method may be called right after the scroll position is created
before layout has occurred. In that case, initialRestore
is set to true
and the viewport dimensions will not be known yet. If the context
doesn't have any information to restore the scroll offset this method is
not called.
The method may be called multiple times in the lifecycle of a ScrollPosition to restore it to different scroll offsets.
Implementation
@override
void restoreOffset(double offset, {bool initialRestore = false}) {
assert(initialRestore != null);
assert(offset != null);
if (initialRestore) {
_pageToUseOnStartup = offset;
} else {
jumpTo(getPixelsFromPage(offset));
}
}