Swift4开发：iOS10下返回页面后TableView出现上下偏移问题求助

Hey there, fellow Swift 4 newbie! I’ve run into this exact weird TableView jump issue before on iOS 10 devices, so let’s break down why it’s happening and how to fix it.

Why This Happens #

The root cause boils down to a difference in how iOS 10 and iOS 11 handle scroll view insets:

• On iOS 10 and earlier, view controllers use the automaticallyAdjustsScrollViewInsets property (default is true) to automatically tweak scroll view insets based on navigation bars, tab bars, or layout guides. Since you’ve reserved a custom top bar area, this automatic adjustment gets confused when navigating back, causing the TableView to jump up and down.
• iOS 11 replaced this property with UIScrollView.contentInsetAdjustmentBehavior, which has smarter default logic—hence why you don’t see the issue in the iOS 11 simulator.

Step-by-Step Fixes #

1. Disable Automatic Inset Adjustment & Set Manual Insets

First, turn off the automatic inset adjustment for your view controller, then manually set the TableView’s insets to account for your custom top bar:

override func viewDidLoad() {
    super.viewDidLoad()
    
    // Disable automatic inset adjustment
    self.automaticallyAdjustsScrollViewInsets = false
    
    // Replace with your actual custom top bar height
    let customTopBarHeight: CGFloat = 60.0 
    tableView.contentInset = UIEdgeInsets(top: customTopBarHeight, left: 0, bottom: 0, right: 0)
    tableView.scrollIndicatorInsets = tableView.contentInset
}

2. Verify TableView Constraints

Double-check your TableView’s constraints to ensure they’re tied correctly to your custom top bar, not the view controller’s default layout guides:

• Set the TableView’s top constraint to the bottom of your custom label bar instead of topLayoutGuide.bottom. This avoids unexpected system-driven layout shifts when navigating back.

3. Preserve Content Offset (If Needed)

If the jump still lingers after the above steps, manually save and restore the TableView’s scroll position when navigating:

// Store the last scroll offset before leaving the view
private var lastTableViewOffset: CGPoint = .zero

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)
    lastTableViewOffset = tableView.contentOffset
}

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    // Restore the offset without animation to prevent jumping
    tableView.setContentOffset(lastTableViewOffset, animated: false)
}

Testing Tip #

Since this issue only pops up on your iOS 10 iPhone SE (not the iOS 11 simulator), make sure to test directly on that physical device after applying the fixes—simulators can sometimes behave differently with layout logic.

内容的提问来源于stack exchange，提问作者CamiloR