智能横幅广告是一种广告单元，可在任何屏幕上呈现与屏幕等宽的横幅广告 以任意屏幕方向呈现广告的尺寸智能横幅广告可以检测设备处于当前屏幕方向时的宽度，并据此创建与之等宽的广告视图。
在 iPhone 上，智能横幅广告在纵向模式下的高度为 50 点，在 iPhone 屏幕中的高度为 32 点。 横向图片。在 iPad 上，智能横幅广告高度在屏幕为纵向和横向时均为 90 点。
当图片广告不足以占据分配的整个空间时， 图片将居中放置，并填充两侧的空白区域。
要使用智能横幅，只需指定 kGADAdSizeSmartBannerPortrait
（适用于纵向屏幕）或 kGADAdSizeSmartBannerLandscape（适用于横向屏幕）
尺寸：
Swift
let bannerView = GADBannerView(adSize: kGADAdSizeSmartBannerPortrait)
Objective-C
GADBannerView *bannerView = [[GADBannerView alloc] initWithAdSize:kGADAdSizeSmartBannerPortrait];
由于 iOS 11 增加了安全区域，因此对于全宽横幅广告， 也应该对横幅广告的边缘添加约束条件 安全区域以下代码段展示了如何执行此操作：
Swift
func addBannerViewToView(_ bannerView: GADBannerView) { bannerView.translatesAutoresizingMaskIntoConstraints = false view.addSubview(bannerView) if #available(iOS 11.0, *) { // In iOS 11, we need to constrain the view to the safe area. positionBannerViewFullWidthAtBottomOfSafeArea(bannerView) } else { // In lower iOS versions, safe area is not available so we use // bottom layout guide and view edges. positionBannerViewFullWidthAtBottomOfView(bannerView) } } // MARK: - view positioning @available (iOS 11, *) func positionBannerViewFullWidthAtBottomOfSafeArea(_ bannerView: UIView) { // Position the banner. Stick it to the bottom of the Safe Area. // Make it constrained to the edges of the safe area. let guide = view.safeAreaLayoutGuide NSLayoutConstraint.activate([ guide.leftAnchor.constraint(equalTo: bannerView.leftAnchor), guide.rightAnchor.constraint(equalTo: bannerView.rightAnchor), guide.bottomAnchor.constraint(equalTo: bannerView.bottomAnchor) ]) } func positionBannerViewFullWidthAtBottomOfView(_ bannerView: UIView) { view.addConstraint(NSLayoutConstraint(item: bannerView, attribute: .leading, relatedBy: .equal, toItem: view, attribute: .leading, multiplier: 1, constant: 0)) view.addConstraint(NSLayoutConstraint(item: bannerView, attribute: .trailing, relatedBy: .equal, toItem: view, attribute: .trailing, multiplier: 1, constant: 0)) view.addConstraint(NSLayoutConstraint(item: bannerView, attribute: .bottom, relatedBy: .equal, toItem: bottomLayoutGuide, attribute: .top, multiplier: 1, constant: 0)) }
Objective-C
- (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]]; }