I have a single entry visa to Schengen countries(type c). I will be traveling to Norway from Toronto, Canada. I will stay for a week, then I will travel to Germany. My flight from Norway to Germany will have a transit in London. Will this be a problem with my Single Entry Visa? Will I be able to enter Germany even if I have a transit in London?
No, that will not work
When you depart from Norway towards a non-Schengen country, such as the UK, you will go through Schengen exit formalities. Norway will stamp you out. You'll then fly to London, to do which you'll need to show the airline in question that you're eligible to transit without a visa, which not all nationalities are. See Is there a way to find out if I need a transit visa for a layover in the UK? for details. Then, you'd arrive in Germany as a non-Schengen arrival, and would need to present yourself to German immigration. Your single-entry Schengen visa would not be valid, so they wouldn't let you in. Except, the chances are, you wouldn't be allowed to board the flight from London, as they'd check and spot that
A single-entry Schengen visa is only valid for, as the name suggests, a single entry to the Schengen zone. You can move around within the Schengen zone on it, within the limits of the time allowed on the visa, but when you leave that's it. You'll need to re-book your flights to either be direct, or to have a transit somewhere else in the Schengen zone on the way.