_cmd的详细用法

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//比如需要打印当前被调用的方法，可以在一个方法中添加：

NSLog(@"%@
call",NSStringFromSelector(_cmd));

//会输出类似

//2013-01-10
11:25:46.902 TDDataViewer[855:303] applicationDidFinishLaunching: call

//这样的内容。

//在cocos2d中，_cmd通常用于定时调用某个函数（schedule）

//比如下面方法利用_cmd能够不定时地调用某个函数

-(void)
scheduleUpdates {

    //
schedule the first update as usual

    [self

schedule:@selector(irregularUpdate:)

interval:1];


}

-(void)

irregularUpdate:(ccTime)delta
{

    //
unschedule the method first [self unschedule:_cmd];

    //
I assume you’d have some kind of logic other than random to determine

    //
the next time the method should be called

    float

nextUpdate = CCRANDOM_0_1()
* 10;

    //
then re-schedule it with the new interval using _cmd as the selector

    [self

schedule:_cmd

interval:nextUpdate];


}