4，4s屏幕过渡页处理

    //#import "sys/utsname.h"
    struct utsname systemInfo;
    uname(&systemInfo);
    NSString *deviceString = [NSString stringWithCString:systemInfo.machine encoding:NSUTF8StringEncoding];

    NSLog(@"%@, %@", deviceString, NSStringFromCGSize(self.view.bounds.size));

    imv = [[UIImageView alloc] initWithFrame:self.view.frame];

    NSRange ran = [deviceString rangeOfString:@"iPhone4"];
    NSRange ran1 = [deviceString rangeOfString:@"x86"];
    if(ran.location != NSNotFound || ran1.location != NSNotFound){
        imv.image = [UIImage imageNamed:@"ios640.png"];
    }else{
        imv.image = [UIImage imageNamed:@"wait"];
    }
    [self.view addSubview:imv];