Question

AdMob中的

指出：“可以通过修改所使用的属性和锚点，轻松地将这些技术用于约束安全区域的顶部。”我不确定要在此处更改哪些值，我知道它必须是属性和锚点，但是我不确定如何将其更改为对约束不熟悉

- (void)addBannerViewToView:(UIView *)bannerView {
  bannerView.translatesAutoresizingMaskIntoConstraints = NO;
  [self.view addSubview:bannerView];
  if (@available(ios 11.0, *)) {
    // In iOS 11, we need to constrain the view to the safe area.
    [self positionBannerViewFullWidthAtBottomOfSafeArea:bannerView];
  } else {
    // In lower iOS versions, safe area is not available so we use
    // bottom layout guide and view edges.
    [self positionBannerViewFullWidthAtBottomOfView:bannerView];
  }
}

#pragma mark - view positioning

- (void)positionBannerViewFullWidthAtBottomOfSafeArea:(UIView *_Nonnull)bannerView NS_AVAILABLE_IOS(11.0) {
  // Position the banner. Stick it to the bottom of the Safe Area.
  // Make it constrained to the edges of the safe area.
  UILayoutGuide *guide = self.view.safeAreaLayoutGuide;

  [NSLayoutConstraint activateConstraints:@[
    [guide.leftAnchor constraintEqualToAnchor:bannerView.leftAnchor],
    [guide.rightAnchor constraintEqualToAnchor:bannerView.rightAnchor],
    [guide.bottomAnchor constraintEqualToAnchor:bannerView.bottomAnchor]
  ]];
}

- (void)positionBannerViewFullWidthAtBottomOfView:(UIView *_Nonnull)bannerView {
  [self.view addConstraint:[NSLayoutConstraint constraintWithItem:bannerView
                                                        attribute:NSLayoutAttributeLeading
                                                        relatedBy:NSLayoutRelationEqual
                                                           toItem:self.view
                                                        attribute:NSLayoutAttributeLeading
                                                       multiplier:1
                                                         constant:0]];
  [self.view addConstraint:[NSLayoutConstraint constraintWithItem:bannerView
                                                        attribute:NSLayoutAttributeTrailing
                                                        relatedBy:NSLayoutRelationEqual
                                                           toItem:self.view
                                                        attribute:NSLayoutAttributeTrailing
                                                       multiplier:1
                                                         constant:0]];
  [self.view addConstraint:[NSLayoutConstraint constraintWithItem:bannerView
                                                        attribute:NSLayoutAttributeBottom
                                                        relatedBy:NSLayoutRelationEqual
                                                           toItem:self.bottomLayoutGuide
                                                        attribute:NSLayoutAttributeTop
                                                       multiplier:1
                                                         constant:0]];
}

Answer 1

由于iPhoneX随iOS 11.0及更高版本一起提供，您只需要修改 positionBannerViewFullWidthAtBottomOfSafeArea 函数。无需调整 positionBannerViewFullWidthAtBottomOfView 函数中的约束，该约束适用于11版之前的版本。

更改

[guide.bottomAnchor constraintEqualToAnchor:bannerView.bottomAnchor]

到

[guide.topAnchor constraintEqualToAnchor:bannerView.topAnchor]

这会将AdMob横幅的顶部锚定在指南的顶部。

优雅的解决方案

要缩短admob标准解决方案以在视图中添加横幅并设置所需的约束，以下代码段非常有用。

iOS 11与以前的版本之间的区别是11引入了安全区域。在11之前，iOS拥有LayoutMargins。我们添加了一个小函数来返回“安全区域指南”或布局边距，并通过以下方法摆脱整个 positionBannerViewFullWidthAtBottomOfView 函数：

- (void)addBannerViewToView:(UIView *)bannerView {
  bannerView.translatesAutoresizingMaskIntoConstraints = NO;
  [self.view addSubview:bannerView];

  [self positionBannerViewFullWidthAtBottomOfSafeAreaOrLayoutMargins:bannerView];
}

#pragma mark - view positioning

- (void)positionBannerViewFullWidthAtBottomOfSafeAreaOrLayoutMargins:(UIView *_Nonnull)bannerView {
  // Position the banner. Stick it to the bottom of the Safe Area or layout margins.
  // Make it constrained to the edges of the safe area or layout margins (iOS < 11).
  let guide = correctLayoutGuide

  [NSLayoutConstraint activateConstraints:@[
    [guide.leftAnchor constraintEqualToAnchor:bannerView.leftAnchor],
    [guide.rightAnchor constraintEqualToAnchor:bannerView.rightAnchor],
    [guide.bottomAnchor constraintEqualToAnchor:bannerView.bottomAnchor]
  ]];
}

//Sorry this is Swift code - I don't use ObjC.
//This function returns safeAreaLayoutGuide for iOS 11 and above
//and layoutMarginsGuide for iOS < 11.
var correctLayoutGuide: UILayoutGuide {
        if #available(iOS 11.0, *) {
            return view.safeAreaLayoutGuide
        } else {
            return view.layoutMarginsGuide
        }
    }

将AdMob标语放置在安全区域（iPhoneX）的顶部

1 个答案: