Overlap between life cycle method and push method

Hello,
I have two methods in my component.
the first one is
ionViewDidLeave()
{
// i do some calculation here
}
it will save some objects.
the second one
is
goToDetailsPage($event, object)
{
this.navCtrl.push(DetailsPage, object);
}

if i press the button to go to details page it works. but if i go back i check that my calculation was corrupted.
so i am asking if i can block or not trigger the ionViewDidLeave method if i am going to details page.
if not what should i do

thank you in advance.

I solve the problem
i use ngOnDestroy instead of ionViewDidLeave