Here is the list of conditions for tax filing obligation. As you can see that has nothing to do with being resident or not
http://www.cra-arc.gc.ca/tx/ndvdls/tpcs/ncm-tx/flng-blgtns/menu-eng.html
How much tax you owe and what you have to file depends on your residency.
If you have to file depends on if you owe Canadian taxes. If you made zero income in Canada and aren't residing in Canada, then you don't have to file taxes.
Being a permanent resident or a temporary resident for CIC purposes (= PR, Study Permit, Work Permit etc) is independent of being a resident for tax purposes. These are two different things. If you are not in Canada for the whole year and you don't have any Canadian income, you definitely aren't a resident for tax purposes. If one of these two conditions do not apply to you, then you might be a resident and things get more complicated.
How much tax you owe and what you have to file depends on your residency.
If you have to file depends on if you owe Canadian taxes. If you made zero income in Canada and aren't residing in Canada, then you don't have to file taxes.
Being a permanent resident or a temporary resident for CIC purposes (= PR, Study Permit, Work Permit etc) is independent of being a resident for tax purposes. These are two different things. If you are not in Canada for the whole year and you don't have any Canadian income, you definitely aren't a resident for tax purposes. If one of these two conditions do not apply to you, then you might be a resident and things get more complicated.