Make NSBezierPath to stay relative to the NSView on windowResize

Question

In my program I'm drawing some shapes inside an NSView using NSBezierPath. Everything works and looks great except when I resize the window.

Example

Initial drawing

Window resize

Does anyone know what I should use to prevent this square from being anchored to the initial position, but make it readjust relative the the initial scale.

Any help is appreciated!

Answer 1

If you are doing your drawing in drawRect: then the answer is NO. You will need to rebuild and reposition your path each time. What you can do is something along the following lines:

- (void) drawRect:(NSRect)dirtyRect
{
    // Assuming that _relPos with x and y having values bewteen 0 and 1.
    // To keep the square in the middle of the view you would set _relPos to
    // CGPointMake(0.5, 0.5).

    CGRect bounds = self.bounds;

    CGRect rect;
    rect.size.width  = 100;
    rect.size.height = 100;
    rect.origin.x = bounds.origin.x + bounds.size.width  * _relPos.x - rect.size.width /2;
    rect.origin.y = bounds.origin.y + bounds.size.height * _relPos.y - rect.size.height/2;

    NSBezierPath *path = [NSBezierPath bezierPathWithRect:rect];
    [[NSColor redColor] set];
    path.lineWidth = 2; 
    [path stroke];
}