Objective c 如何添加UIView并覆盖整个屏幕

我试图添加一个灰色的uiview覆盖使用自动布局，以便当你旋转设备时，它仍然自动覆盖整个屏幕。如何通过编程实现这一点？

试试以下方法：

UIView *greyView = [UIView new];
[self.view addSubview:greyView];
greyView.translatesAutoresizingMaskIntoConstraints = NO;
NSDictionary *viewDictionary = @{@“greyView”:greyView};

[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-0-[myView]-0-|“ options:0 metrics:nil views:viewDictionary]];

[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@“H:|-0-[myView0]-0-|” options:0 metrics:nil views:viewDictionary]];

试试这个：

UIView *greyView = [UIView new];
[self.view addSubview:greyView];
greyView.translatesAutoresizingMaskIntoConstraints = NO;
NSDictionary *viewDictionary = @{@“greyView”:greyView};

[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-0-[myView]-0-|“ options:0 metrics:nil views:viewDictionary]];

[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@“H:|-0-[myView0]-0-|” options:0 metrics:nil views:viewDictionary]];

---

这很简单，您需要4个约束条件才能做到这一点-顶部、底部、左侧和右侧：

NSLayoutConstraint *topConstraint = [NSLayoutConstraint constraintWithItem:view attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:superview attribute:NSLayoutAttributeTop multiplier:1.0f constant:0.0f];
NSLayoutConstraint *bottomConstraint = [NSLayoutConstraint constraintWithItem:view attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:superview attribute:NSLayoutAttributeBottom multiplier:1.0f constant:0.0f];
NSLayoutConstraint *leftConstraint = [NSLayoutConstraint constraintWithItem:view attribute:NSLayoutAttributeLeft relatedBy:NSLayoutRelationEqual toItem:superview attribute:NSLayoutAttributeLeft multiplier:1.0f constant:0.0f];
NSLayoutConstraint *rightConstraint = [NSLayoutConstraint constraintWithItem:view attribute:NSLayoutAttributeRight relatedBy:NSLayoutRelationEqual toItem:superview attribute:NSLayoutAttributeRight multiplier:1.0f constant:0.0f];

---

这很简单，您需要4个约束条件才能做到这一点-顶部、底部、左侧和右侧：

NSLayoutConstraint *topConstraint = [NSLayoutConstraint constraintWithItem:view attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:superview attribute:NSLayoutAttributeTop multiplier:1.0f constant:0.0f];
NSLayoutConstraint *bottomConstraint = [NSLayoutConstraint constraintWithItem:view attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:superview attribute:NSLayoutAttributeBottom multiplier:1.0f constant:0.0f];
NSLayoutConstraint *leftConstraint = [NSLayoutConstraint constraintWithItem:view attribute:NSLayoutAttributeLeft relatedBy:NSLayoutRelationEqual toItem:superview attribute:NSLayoutAttributeLeft multiplier:1.0f constant:0.0f];
NSLayoutConstraint *rightConstraint = [NSLayoutConstraint constraintWithItem:view attribute:NSLayoutAttributeRight relatedBy:NSLayoutRelationEqual toItem:superview attribute:NSLayoutAttributeRight multiplier:1.0f constant:0.0f];