这是我第一次尝试使用 typedef。诚然，我对正在发生的事情没有一个非常清楚的想法，但我的理解是 typedef 中的值被分配了从 0 开始的整数。我尝试将它们用作整数，但我得到了各种警告和错误。其中之一是“[NSCFNumber objectForKey:]: unrecognized selector sent to instance”。我不知道如何解决这个问题。我也没有写太多动态 getter/setter，所以我的方法可能是错误的。请帮忙。
// MyView.h
typedef enum
{
STYLE_A,
STYLE_B,
STYLE_C,
STYLE_D
} MyShapeStyle;
@interface MyView : UIView
{
MyShapeStyle shapeStyle;
CALayer *myLayer;
MyLayerDelegate *myLayerDelegate;
}
@property (nonatomic) MyShapeStyle shapeStyle;
@property (nonatomic, retain) CALayer *myLayer;
@property (nonatomic, retain) MyLayerDelegate *myLayerDelegate;
@end
// MyView.m
#import "MyView.h"
@implementation MyView
@dynamic shapeStyle;
@synthesize myLayer;
@synthesize myLayerDelegate;
- (id)initWithFrame:(CGRect)frame
{
if ((self = [super initWithFrame:frame]))
{
// Initialization code
MyLayerDelegate *delegate = [[MyLayerDelegate alloc] init];
self.myLayerDelegate = delegate;
CALayer *myLayer = [CALayer layer];
[myLayer setDelegate:delegate];
[self.layer addSublayer:myLayer];
self.myLayer = myLayer;
self.shapeStyle = STYLE_C;
[delegate release];
}
return self;
}
-(MyShapeStyle)shapeStyle
{
return [[self.myLayer valueForKey:@"style"] integerValue];
}
- (void)setShapeStyle:(MyShapeStyle)style
{
[self.myLayer setValue:[NSNumber numberWithInt:style] forKey:@"style"];
}
// MyLayerDelegate.m
-(void)drawLayer:(CALayer *)theLayer inContext:(CGContextRef)theContext
{
int id = [[theLayer valueForKey:@"style"] integerValue];
if( id == STYLE_A )
{
}else if ( id == STYLE_B ){
}
}