問題描述

我正在調(diào)整詳細(xì)視圖控制器的狀態(tài)，就在它被推送到 navigationController 之前:

I am adjusting a detail view controller's state, just before it is pushed on a navigationController:

[self.detailViewController detailsForObject:someObject];
[self.navigationController pushViewController:self.detailViewController
                                     animated:YES];

在 DetailViewController 中有一個滾動視圖.我根據(jù)傳遞的對象調(diào)整了哪些內(nèi)容的大小:

In the DetailViewController a scrollView resides. Which content I resize based on the passed object:

- (void)detailsForObject:(id)someObject {
    // set some textView's content here
    self.contentView.frame = <rect with new calculated size>;

    self.scrollView.contentSize = self.contentView.frame.size;
    self.scrollView.contentOffset = CGPointZero;
}

現(xiàn)在，這一切正常，但是在 navigationController 的滑入動畫期間，scrollView 會調(diào)整它的 contentOffset.contentOffset 將設(shè)置為最后一個 contentSize 和新計(jì)算的值之間的差異.這意味著第二次打開 detailsView 時，詳細(xì)信息將滾動到某個不需要的位置.即使我將 contentOffset 明確設(shè)置為 CGPointZero.

Now, this all works, but the scrollView adjusts it's contentOffset during the navigationController's slide-in animation. The contentOffset will be set to the difference between the last contentSize and the new calculated one. This means that the second time you open the detailsView, the details will scroll to some unwanted location. Even though I'm setting the contentOffset to CGPointZero explicitly.

我發(fā)現(xiàn)在-viewWillAppear中重置contentOffset沒有效果.我能想到的最好辦法是重置 viewDidAppear 中的 contentOffset，導(dǎo)致內(nèi)容明顯上下移動:

I found that resetting the contentOffset in - viewWillAppear has no effect. The best I could come up with is resetting the contentOffset in viewDidAppear, causing a noticeable up and down movement of the content:

- (void)viewDidAppear:(BOOL)animated {
    self.scrollView.contentOffset = CGPointZero;
}

有沒有辦法防止 UIScrollView 在其 contentSize 更改時調(diào)整其 contentOffset?

Is there a way to prevent a UIScrollView from adjusting its contentOffset when its contentSize is changed?

推薦答案

在使用 UINavigationController 推送包含 UIScrollView 的 UIViewController 時發(fā)生.

Occurs when pushing a UIViewController containing a UIScrollView using a UINavigationController.

iOS 11+

解決方案 1(Swift 代碼):

scrollView.contentInsetAdjustmentBehavior = .never

解決方案 2(故事板)

iOS 7

解決方案 1(代碼)

設(shè)置 @property(nonatomic, assign) BOOL automaticallyAdjustsScrollViewInsets 到 NO.

解決方案 2(故事板)

取消選中調(diào)整滾動視圖插圖

iOS 6

解決方案(代碼)

在viewWillLayoutSubviews中設(shè)置UIScrollView的屬性contentOffset和contentInset.示例代碼:

Set the UIScrollView's property contentOffset and contentInset in viewWillLayoutSubviews. Sample code:

- (void)viewWillLayoutSubviews{
  [super viewWillLayoutSubviews];
  self.scrollView.contentOffset = CGPointZero;
  self.scrollView.contentInset = UIEdgeInsetsZero;
}

這篇關(guān)于UIScrollView 在 contentSize 改變時調(diào)整 contentOffset的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網(wǎng)！