Graphics Reference
In-Depth Information
LISTING 4-4
Continued
target
:
self
selector
:
@selector
(legTwo:)
userInfo
:
nil
repeats
:
NO
];
[
NSTimer scheduledTimerWithTimeInterval
:6.0
target
:
self
selector
:
@selector
(legThree:)
userInfo
:
nil
repeats
:
NO
];
[
NSTimer scheduledTimerWithTimeInterval
:8.0
target
:
self
selector
:
@selector
(legFour:)
userInfo
:
nil
repeats
:
NO
];
[
NSTimer scheduledTimerWithTimeInterval
:10.0
target
:
self
selector
:
@selector
(legFive:)
userInfo
:
nil
repeats
:
NO
];
// Tell the root layer to call drawLayer
[[[window
contentView
]
layer
]
setNeedsDisplay
];
}
As each time is reached, another point is added to the
starPath
path, and the root layer
updates its display, as shown in Listing 4-5. The final call,
legFive
, closes the path.
LISTING 4-5
Selector Methods for Each Timer Add a New Point to the Path
- (
void
)legOne:(
id
)sender
{
CGPathAddLineToPoint
(starPath,
NULL
, 181.0, 99.0);
[[[window
contentView
]
layer
]
setNeedsDisplay
];
}
- (
void
)legTwo:(
id
)sender
{
CGPathAddLineToPoint
(starPath,
NULL
, 335.0, 210.0);
[[[window contentView] layer] setNeedsDisplay];
}
