ios9-NSLayoutAnchor和UILayoutGuide实现自动布局

@interface ViewController () { NSLayoutConstraint *yellowViewTopConstraint; NSLayoutConstraint *blueViewLeadConstraint; } @end

@implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; UILayoutGuide *view_Guide = self.view.layoutMarginsGuide; /** 左边黄色view */ UIView *yellow_View = [[UIView alloc]init]; yellow_View.backgroundColor = [UIColor yellowColor]; yellow_View.translatesAutoresizingMaskIntoConstraints = NO; [self.view addSubview:yellow_View]; //左边距约束
    NSLayoutConstraint *yellowView_Leading = [yellow_View.leadingAnchor constraintEqualToAnchor:view_Guide.leadingAnchor constant:10]; //顶部约束
    NSLayoutConstraint *yellowView_Top = [yellow_View.topAnchor constraintEqualToAnchor:view_Guide.topAnchor constant:84]; //宽度约束
    NSLayoutConstraint *yellowView_Width = [yellow_View.widthAnchor constraintEqualToConstant:100]; //高度约束
    NSLayoutConstraint *yellow_Height = [yellow_View.heightAnchor constraintEqualToConstant:100]; [NSLayoutConstraint activateConstraints:@[yellowView_Leading,yellowView_Top,yellow_Height,yellowView_Width]]; yellowViewTopConstraint = yellowView_Top; /** 居中的红色view */ UIView *middleView = [[UIView alloc]init]; middleView.backgroundColor = [UIColor redColor]; middleView.translatesAutoresizingMaskIntoConstraints = NO; [self.view addSubview:middleView]; //水平居中
    NSLayoutConstraint *middleView_CenterX = [middleView.centerXAnchor constraintEqualToAnchor:view_Guide.centerXAnchor]; //垂直居中
    NSLayoutConstraint *middleView_CenterY = [middleView.centerYAnchor constraintEqualToAnchor:view_Guide.centerYAnchor]; //宽度约束
    NSLayoutConstraint *middleView_Width = [middleView.widthAnchor constraintEqualToConstant:100]; //高度约束
    NSLayoutConstraint *middleView_Height = [middleView.heightAnchor constraintEqualToConstant:100]; [NSLayoutConstraint activateConstraints:@[middleView_CenterX,middleView_CenterY,middleView_Height,middleView_Width]]; /** * 创建一个与黄色view相聚10的蓝色view */ UIView *blueView = [[UIView alloc]init]; blueView.backgroundColor = [UIColor blueColor]; blueView.translatesAutoresizingMaskIntoConstraints = NO; [self.view addSubview:blueView]; //左边约束
    NSLayoutConstraint *blueView_Leading = [blueView.leadingAnchor constraintEqualToAnchor:yellow_View.trailingAnchor constant:10]; //顶部约束于黄色view顶部对齐
    NSLayoutConstraint *blueView_Top = [blueView.topAnchor constraintEqualToAnchor:yellow_View.topAnchor]; //宽度约束
    NSLayoutConstraint *blueView_Width = [blueView.widthAnchor constraintEqualToConstant:100]; //高度约束
    NSLayoutConstraint *blueView_Height = [blueView.heightAnchor constraintEqualToConstant:100]; [NSLayoutConstraint activateConstraints:@[blueView_Leading,blueView_Top,blueView_Width,blueView_Height]]; blueViewLeadConstraint = blueView_Leading; //创建一个执行动画按钮
 UIButton *btnAnimate = [UIButton buttonWithType:UIButtonTypeCustom]; [btnAnimate setBackgroundColor:[UIColor redColor]]; [btnAnimate setTitleColor:[UIColor blackColor] forState:UIControlStateNormal]; [btnAnimate setTitle:@"执行动画" forState:UIControlStateNormal]; [btnAnimate addTarget:self action:@selector(btnAnimateClick:) forControlEvents:UIControlEventTouchUpInside]; btnAnimate.translatesAutoresizingMaskIntoConstraints = NO; [self.view addSubview:btnAnimate]; //水平居中
    NSLayoutConstraint *btnAnimate_CenterX = [btnAnimate.centerXAnchor constraintEqualToAnchor:view_Guide.centerXAnchor]; //底部约束
    NSLayoutConstraint *btnAnimate_Bottom = [btnAnimate.bottomAnchor constraintEqualToAnchor:view_Guide.bottomAnchor constant:-20]; //宽度约束
    NSLayoutConstraint *btnAnimate_Width = [btnAnimate.widthAnchor constraintEqualToConstant:80]; //高度约束
    NSLayoutConstraint *btnAnimate_Height = [btnAnimate.heightAnchor constraintEqualToConstant:32]; [NSLayoutConstraint activateConstraints:@[btnAnimate_Height,btnAnimate_Width,btnAnimate_CenterX,btnAnimate_Bottom]]; } - (void)btnAnimateClick:(UIButton *)sender { [UIView animateKeyframesWithDuration:1 delay:0 options:UIViewKeyframeAnimationOptionRepeat animations:^{ yellowViewTopConstraint.constant += 10; blueViewLeadConstraint.constant += 10; [self.view layoutIfNeeded]; } completion:^(BOOL finished) { }]; }