?
UIView *blueView = [[UIView alloc] init];
??? [self.view addSubview:blueView];
??? blueView.backgroundColor = [UIColor blueColor];
???
??? blueView.center = self.view.center;
??? blueView.bounds = CGRectMake(0, 0, 150, 150);
??? self.blueView = blueView;
???
??? /*
???? Flexible 灵活的,自由的
????
???? typedef NS_OPTIONS(NSUInteger, UIViewAutoresizing) {
???? UIViewAutoresizingNone ??????????????? = 0,
???? UIViewAutoresizingFlexibleLeftMargin ? = 1 << 0,
// ? 左边是自由的,右边是固定的(与storyboard中相反)
???? UIViewAutoresizingFlexibleWidth??????? = 1 << 1,
// ? 宽度是可拉伸的
????
???? UIViewAutoresizingFlexibleRightMargin? = 1 << 2,
//??? 右边是自由的,左边是固定的(与storyboard中相反)
???? UIViewAutoresizingFlexibleTopMargin??? = 1 << 3,
//??? 顶部是自由的,底部是固定的(与storyboard中相反)
???? UIViewAutoresizingFlexibleHeight ????? = 1 << 4,
// ? 高度是自由的(高度是可拉伸的)
???? UIViewAutoresizingFlexibleBottomMargin = 1 << 5
//??? 底部是自由的,顶部是固定的(与storyboard中相反)
???? };
????
????
???? */
//? 四周固定,中间灵活
//??? redView.autoresizingMask? = ? UIViewAutoresizingFlexibleWidth|UIViewAutoresizingFlexibleHeight;
//? 四周灵活,中间固定
//? 多个通过 "|" 进行连接
? ? blueView.autoresizingMask = UIViewAutoresizingFlexibleLeftMargin|UIViewAutoresizingFlexibleTopMargin|UIViewAutoresizingFlexibleRightMargin|UIViewAutoresizingFlexibleBottomMargin;
? ?
IOS中级篇 —— Autoresizing
原文：http://www.cnblogs.com/deng1989/p/4595294.html
