A.用CCFuncBlock可以不用传参数,代码简洁高效,函数内临时变量如果不retain,不存在跳出函数使用域后被回收情况(推荐)
//用CCCallBlock的block方式 CGPoint convertedLocation = [self convertTouchToNodeSpace:touch]; CCCallBlock *block = [CCCallBlock actionWithBlock:^{ //回调方法在一个函数循环内3个好处:
1.不用传递(void *)参数,所以convertedLocation不需要封装,
2.传递指针类型变量(非alloc或copy)也不需要retain,
3.alloc或copy方式产生的参数,函数内释放,省去函数外手动释放的麻烦。
[self flightBezier:convertedLocation];
}];
[flight runAction:[CCSequence actions:[CCMoveTo actionWithDuration:1 position:ccp(convertedLocation.x,convertedLocation.y)], block, nil]];
B.使用CCFuncND传递参数(void *)类型,若想传递CGPoint等非指针类型参数,,有两种方法:
1.传递参数地址,注意参数必须为静态变量,否则参数地址一出循环即被系统回收。
-(void) ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event { UITouch *touch = [touches anyObject]; static _startPos; CGPoint convertedLocation = [self convertTouchToNodeSpace:touch]; _startPos = converedLocation; //传递&_startPos id call = [CCCallFuncND actionWithTarget:self selector:@selector(call:data:) data:(void *)&_startPos]; [flight runAction:[CCSequence actions:[CCMoveTo actionWithDuration:1 position:ccp(convertedLocation.x,convertedLocation.y)], call, nil]]; return; }
回调:
- (void)call:(id)sender data:(void *)point {
//sender即为flight指针 //传递&_startPos; CGPoint p = *(CGPoint *) point; [self flightBezier:p]; }
2.如果想传递CGPoint等非指针类型变量, 可以封装成NSValue再传递
-(void) ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event { UITouch *touch = [touches anyObject]; static _startPos; CGPoint convertedLocation = [self convertTouchToNodeSpace:touch]; _startPos =converedLocation; //传递nsvalue封装的cgpoint NSValue *va = [[NSValuevalueWithCGPoint:convertedLocation]retain];//这里不能加autorease id call1 = [CCCallFuncND actionWithTarget:self selector:@selector(call:data:) data:(void *)va]; [flight runAction:[CCSequence actions:[CCMoveTo actionWithDuration:1 position:ccp(convertedLocation.x,convertedLocation.y)], call1, nil]]; return; }
回调:
- (void)call:(id)sender data:(void *)point { //传递nsvalue CGPoint p = [((NSValue *)point) CGPointValue];
//父变量,子释放,比较忌讳,但是没找到好的解决办法先凑合用 [(NSValue *)point release]; point = nil; [self flightBezier:p]; }