iOS UIViewController 模态视图 根据内容显示Size

UICustomViewController *customvc = [UICustomViewController new];

UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:customvc];

nav.modalPresentationStyle = UIModalPresentationFormSheet;

[self presentViewController:customvc animated:YES completion:nil];

需要在UICustomViewController的 viewWillAppear: 方法中 设置 frame

• (void)viewWillAppear:(BOOL)animated{

  [super viewWillAppear:animated];

  GCFloat topY = 120;

  self.navigationController.view.superview.frame = CGRectMake(0, topY, SCREEN_WIDTH, SCREEN_HEIGHT - topY);

}

以上是可根据内容设置显示区域大小

还有一种是iOS15的显示半屏或者全屏的方法

控制器的 sheetPresentationController 属性

        UISheetPresentationController *sheet = self.sheetPresentationController;
        sheet.detents = @[UISheetPresentationControllerDetent.mediumDetent,
                          UISheetPresentationControllerDetent.largeDetent ];
        sheet.smallestUndimmedDetentIdentifier = UISheetPresentationControllerDetentIdentifierMedium;
        sheet.prefersScrollingExpandsWhenScrolledToEdge = false;
        sheet.prefersEdgeAttachedInCompactHeight = true;
        sheet.widthFollowsPreferredContentSizeWhenEdgeAttached = true;

类似于调取原生分享时的效果，可以半屏，往上拖动就是全屏