NSRect on main screen without window

Question

I was wondering if it is possible to create an NSRect with maybe an NSMakeRect to make a simple square that will display on the screen without a window or any view behind it, just made all in code.

This is what I have as an example

-(void)drawRect
{
   NSRect myNewRect
   myNewRect = NSMakeRect(100, 100, 50, 50);
}

Thats just a simple starting point but it will not show up on the screen by itself. what do i need to add?

Thanks

To display an NSRect you have to draw it somewhere. – sch Feb 18 '12 at 22:19 — sch, Feb 18 '12 at 22:19

score 2 · Accepted Answer · answered Feb 18 '12 at 22:22

2

Every drawing operation on Mac OS X requires some window of sort. So no, you cannot draw a rect without a window. But you can create a transparent window without any borders to draw into.

answered Feb 18 '12 at 22:22

DarkDust

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score 1 · Answer 2 · answered Feb 18 '12 at 22:21

First of all, you can't "display on the screen without a window or any view behind it".

You will always be drawing on some layer-backed object (UIView, etc).

And UIViews must eventually be part of some UIWindow hierarchy to display them.

So you can't "[draw] on main screen without window" at all. That's not how Core Graphics works.

However, I believe this is what you're trying to do:

-(void)drawRect
{
   CGRect myNewRect = CGRectMake(100, 100, 50, 50);

   CGContextRef ctx = UIGraphicsGetCurrentContext();
   CGContextSetFillColorWithColor(ctx, [[UIColor redColor] CGColor]);
   CGContextFillRect(ctx, myNewRect);
}

Which draws a rectangle in the UIView implementing the above drawRect method.

NSRect on main screen without window

2 Answers2