IOS常用API

1.弹窗

UIAlertView *alert = [[UIAlertView alloc] 

                          initWithTitle:@"Error getting Location" 

                          message:errorType 

                          delegate:nil 

                          cancelButtonTitle:@"Okay" 

                          otherButtonTitles:nil];

    [alert show];

    [alert release];

UIAlertView *alert = [[UIAlertView alloc] init];

        [alert setTitle:@"Error"];

        [alert setMessage:@"This device is not support camera!"];

        [alert setDelegate:self];

        [alert addButtonWithTitle:@"Colse"];

        [alert show];

        [alert release];

2.调用嘀嗒数

CFAbsoluteTimeGetCurrent()

3. 随机数

u_int32_t arc4random(void); 在stdlib.h 文件中