Thank you all, Thanks a lot.
Finally I found a trick,
First you should hide the Status Bar during launch. By just doing this Xcode -> project Targets -> summary Tab -> Status Bar -> check the visibility.
Then, set
[imgsplash setImage:[UIImage imageNamed:@"Default"]];
imgsplash.frame = CGRectMake([[UIScreen mainScreen] bounds].origin.x,
[[UIScreen mainScreen] bounds].origin.y,
[[UIScreen mainScreen] bounds].size.width,
[[UIScreen mainScreen] bounds].size.height);
imgsplash.autoresizingMask = UIViewAutoresizingFlexibleBottomMargin |
UIViewAutoresizingFlexibleTopMargin |
UIViewAutoresizingFlexibleLeftMargin |
UIViewAutoresizingFlexibleRightMargin;
by giving [UIImage imageNamed:@"Default"] let the imageNamed can choose right image.
Thanks.