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Issue Info

Issue Description and Steps

When an SDAnimatedImagePlayer creates a SDDisplayLink in -[SDAnimatedImagePlayer displayLink] the SDDisplayLink is not released when the SDAnimatedImagePlayer is deallocated. This results in a proliferation of CVDisplayLink threads.

The current implementation of '-[SDAnimatedImagePlayer dealloc]' is:

- (void)dealloc {
    // Dereference the frame pool, when zero the frame pool for provider will dealloc
    [SDImageFramePool unregisterProvider:self.animatedProvider];
}

And I se nothing that would suggest that the SDDisplayLink is stopped or removed from the RunLoop. When I change the code to something link:

- (void)dealloc {
    // Dereference the frame pool, when zero the frame pool for provider will dealloc
    [SDImageFramePool unregisterProvider:self.animatedProvider];
    [_displayLink stop];
    [_displayLink removeFromRunLoop:[NSRunLoop mainRunLoop] forMode:_runLoopMode];
}

Then I no longer see a proliferation of CVDisplayLink threads (as seen in Xcode):

It is unclear if this is the correct solution to prevent the leak or if a better solution is available.