以编程方式在UIStackView中添加视图

堆栈视图使用内部内容大小，因此使用布局约束来定义视图的尺寸。

有一种简单的方法可以快速添加约束（示例）：

  [view1.heightAnchor constraintEqualToConstant：100] .active = true; 

完整代码：

  -（void）setup {//查看1 
  UIView * view1 = [[UIView alloc] init]; 
  view1.backgroundColor = [UIColor blueColor]; 
  [view1.heightAnchor constraintEqualToConstant：100] .active = true; 
  [view1.widthAnchor constraintEqualToConstant：120] .active = true; 
  //查看2 
  UIView * view2 = [[UIView alloc] init]; 
  view2.backgroundColor = [UIColor greenColor]; 
  [view2.heightAnchor constraintEqualToConstant：100] .active = true; 
  [view2.widthAnchor constraintEqualToConstant：70] .active = true;  //查看3 
  UIView * view3 = [[UIView alloc] init]; 
  view3.backgroundColor = [UIColor洋红色]; 
  [view3.heightAnchor constraintEqualToConstant：100] .active = true; 
  [view3.widthAnchor constraintEqualToConstant：180] .active = true;  //堆栈视图 
  UIStackView * stackView = [[UIStackView alloc] init];  stackView.axis = UILayoutConstraintAxisVertical; 
  stackView.distribution = UIStackViewDistributionEqualSpacing; 
  stackView.alignment = UIStackViewAlignmentCenter; 
  stackView.spacing = 30; 
  [stackView addArrangedSubview：view1]; 
  [stackView addArrangedSubview：view2]; 
  [stackView addArrangedSubview：view3];  stackView.translatesAutoresizingMaskIntoConstraints = false; 
  [self.view addSubview：stackView]; 
  //堆栈视图的布局 
  [stackView.centerXAnchor constraintEqualToAnchor：self.view.centerXAnchor] .active = true; 
  [stackView.centerYAnchor constraintEqualToAnchor：self.view.centerYAnchor] .active = true; 
  } 

注意：这已在iOS 9上进行了测试