iOS开发 autoResizingMask使用

时间:2021-03-07 20:31:07

autoResizingMask 是UIView的一个属性,在一些简单的布局中,使用autoResizingMask,可以实现子控件相对于父控件的自动布局。

autoResizingMask 是UIViewAutoresizing 类型的,其定义为:

@property(nonatomic) UIViewAutoresizing autoresizingMask;    // simple resize. default is UIViewAutoresizingNone

UIViewAutoresizing 是一个枚举类型,默认是 UIViewAutoresizingNone,其可以取得值有:

typedef NS_OPTIONS(NSUInteger, UIViewAutoresizing) {
UIViewAutoresizingNone = ,
UIViewAutoresizingFlexibleLeftMargin = << ,
UIViewAutoresizingFlexibleWidth = << ,
UIViewAutoresizingFlexibleRightMargin = << ,
UIViewAutoresizingFlexibleTopMargin = << ,
UIViewAutoresizingFlexibleHeight = << ,
UIViewAutoresizingFlexibleBottomMargin = <<
};

各属性解释:

UIViewAutoresizingNone

不会随父视图的改变而改变

UIViewAutoresizingFlexibleLeftMargin

自动调整view与父视图左边距,以保证右边距不变

UIViewAutoresizingFlexibleWidth

自动调整view的宽度,保证左边距和右边距不变

UIViewAutoresizingFlexibleRightMargin

自动调整view与父视图右边距,以保证左边距不变

UIViewAutoresizingFlexibleTopMargin

自动调整view与父视图上边距,以保证下边距不变

UIViewAutoresizingFlexibleHeight

自动调整view的高度,以保证上边距和下边距不变

UIViewAutoresizingFlexibleBottomMargin

自动调整view与父视图的下边距,以保证上边距不变

注意:autoResizingMask 既可以在代码中直接使用,也可以在UIStoryboard中使用。

一个代码中使用autoResizingMask的例子:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
UIViewController *viewController = [[UIViewController alloc] init];
self.window.rootViewController = viewController;
self.window.backgroundColor = [UIColor whiteColor]; UIView *view = [[UIView alloc] initWithFrame:CGRectMake(,,,)];
[view setBackgroundColor:[UIColor grayColor]];
[self.window addSubview:view]; UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(,,,)];
[button setBackgroundColor:[UIColor whiteColor]];
[view addSubview:button];
//距离父视图右边距不变
//button.autoresizingMask = UIViewAutoresizingFlexibleLeftMargin;
//距离父视图的左边距不变
//button.autoresizingMask = UIViewAutoresizingFlexibleRightMargin;
//距离父视图的左右边距不变,button大小会调整
//button.autoresizingMask = UIViewAutoresizingFlexibleWidth;
//view.frame = CGRectMake(20,100,300,100); //距离父视图的下边距不变
//button.autoresizingMask = UIViewAutoresizingFlexibleTopMargin;
//距离父视图的上边距不变
//button.autoresizingMask = UIViewAutoresizingFlexibleBottomMargin;
//距离父视图的上下边距不变,button大小会调整
button.autoresizingMask = UIViewAutoresizingFlexibleHeight;
view.frame = CGRectMake(,,,); [self.window makeKeyAndVisible];
return YES;
}

另外,autoResizingMask 可以组合使用。例如:

button.autoresizingMask = UIViewAutoresizingFlexibleBottomMargin | UIViewAutoresizingFlexibleLeftMargin;

表示的是,子控件相对于父控件的顶部和右侧的距离不变。