handleBack method
Implementation
LmBackResult handleBack({
LmNavigationSource source = LmNavigationSource.systemBack,
}) {
assert(
source == LmNavigationSource.systemBack ||
source == LmNavigationSource.gestureBack ||
source == LmNavigationSource.programmaticPop,
'Back handling should use a back-like navigation source.',
);
return pop() ? LmBackResult.handled : LmBackResult.allowSystem;
}