Basic Animations - Core Animation - page 34

14. In the MainMenu.xib , Control-click on AppDelegate and drag the connection to the
Window object. Select window in the ensuing context menu.
15. Save the xib file and return to Xcode.
The project is now set up. In the preceding steps, we created an application delegate that
we use to provide control to our layer, window, and view.
Add the Animation Layer to the Root Layer
To add a layer that we will be animating, do the following:
1. Open AppDelegate.h and add a CALayer instance variable:
@interface AppDelegate : NSObject
{
IBOutlet NSWindow *window;
CALayer *layer;
}
2. Open AppDelegate.m and add the layer initialization code in -awakeFromNib :
@implementation AppDelegate
- ( void )awakeFromNib;
{
[[window contentView ] setWantsLayer: YES ];
layer = [ CALayer layer ];
[layer setBounds:CGRectMake(0.0, 0.0, 100.0, 100.0)];
// Center the animation layer
[layer setPosition : CGPointMake ([[window contentView ]
frame ]. size.width /2,
[[window contentView ]
frame ]. size . height /2)];
CGColorRef color = CGColorCreateGenericRGB (0.4, 0.3, 0.2, 1);
[layer setBackgroundColor :color];
CFRelease (color);
[layer setOpacity :0.75];
[layer setBorderWidth :5.0f];
[[[window contentView ] layer ] addSublayer :layer];
}
@end