drawRect not called on PDFView subclass - cocoa

Question

I have a custom PDFView subclass and have overridden -mouseDown, -mouseDragged etc to draw a rectangle over the view. Here is the code I am using:
#implementation MyPDFView {
NSPoint clickLocation;
NSRect selection;
}
- (void)mouseDown:(NSEvent *)theEvent {
NSPoint clickLocationOnWindow = [self.window mouseLocationOutsideOfEventStream];
clickLocation = [self convertPoint:clickLocationOnWindow fromView:nil];
NSLog(#"%#", NSStringFromPoint(clickLocation));
}
- (void)mouseDragged:(NSEvent *)theEvent {
NSPoint mouseLocationOnWindow = [self.window mouseLocationOutsideOfEventStream];
NSPoint currentLocation = [self convertPoint:mouseLocationOnWindow fromView:nil];
CGFloat lowerX = fmin(clickLocation.x, currentLocation.x);
CGFloat lowerY = fmin(clickLocation.y, currentLocation.y);
CGFloat upperX = fmax(clickLocation.x, currentLocation.x);
CGFloat upperY = fmax(clickLocation.y, currentLocation.y);
selection = NSMakeRect(lowerX, lowerY, upperX-lowerX, upperY-lowerY);
[self setNeedsDisplay:YES];
NSLog(#"%#", NSStringFromRect(selection));
}
- (void)drawRect:(NSRect)dirtyRect
{
// Drawing code here.
NSLog(#"drawRect");
NSBezierPath *bp = [NSBezierPath bezierPathWithRect:selection];
[[NSColor blueColor] set];
[bp fill];
}
#end
The NSRect is calculated correctly, but when I call [self setNeedsDisplay], -drawRect is never called, and the rectangle is never drawn.
Is there any reason why -drawRect is never called on a PDFView subclass?

Answer 1

I have a similar use case. According to the docs, override PDFView's drawPage method instead. Continue to call setNeedsDisplay on the PDFView. It works, but it's a little slow. Working on overlaying a view right now instead.