First Quartz 2D program giving errors... What's the mistake?

I am trying to make my first Quartz 2D app for MAC. I just have my app delegate and a myView class which is as below -

mydrawAppDelegate.h --

#import <Cocoa/Cocoa.h>

@class myView;

@interface mydrawAppDelegate : NSObject <NSApplicationDelegate> {
NSWindow *window;

myView* view;
}

@property (assign) IBOutlet NSWindow *window;

@end

mydrawAppDelegate.m -

#import "mydrawAppDelegate.h"
#import "myView.h"

@implementation开发者_如何学C mydrawAppDelegate

@synthesize window;

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification {
// Insert code here to initialize your application 

view = [[myView alloc] initWithFrame:CGRectMake(0.0, 0.0, 300.0, 480.0) ];
[[self.window contentView] addSubview:view];
}   
@end

myView.h -

#import <Cocoa/Cocoa.h>
#import <Quartz/Quartz.h>
#import <AppKit/AppKit.h>

@interface myView : NSView {

}

@end

myView.m -

#import "myView.h"

@implementation myView

- (id)initWithFrame:(NSRect)frame {
self = [super initWithFrame:frame];
if (self) {
    // Initialization code here.

    NSLog(@"initwithframeeeeeee");
}
return self;
}

- (void)drawRect:(NSRect)dirtyRect {
  // Drawing code here.
NSLog(@"drawrect called");
CGContextRef context = [[NSGraphicsContext currentContext] graphicsPort];

CGContextSetLineWidth(context, 2.0);
CGContextSetStrokeColorWithColor(context, [NSColor redColor]);
CGContextMoveToPoint(context, 100.0f, 100.0f);
CGContextAddLineToPoint(context, 300.0f, 300.0f);
CGContextStrokePath(context);
}

@end

It builds but gives "EXC_BAD_ACCESS" while running. And a compile time warning: "passing argument 2 of 'CGContextSetStrokeColorWithColor' from incompatible pointer type "

Also I am not using any nib file. Do we use nib file when we draw using quartz or not? Kindly help. Thanks...

---

Got the problem. NSColor cannot be directly converted to CGColor. commented the line

     CGContextSetStrokeColorWithColor(context, [NSColor redColor]);

and it works fine. Further changed color to red color using cgcreatecolor. :)