iOS开发：点击导航栏按钮切换TableView分区表头的显示与隐藏

Hey there! Let's get that sticky, toggleable search bar sorted out for your iOS app. Here's a step-by-step solution tailored to your setup with Xcode 9.3 and Swift:

1. Declare Required Properties #

First, add these properties to your TableViewController class to manage the search bar and its visibility state:

import UIKit

class TableViewController: UITableViewController, UISearchBarDelegate { // Add delegate if you need search functionality
    
    private let searchBar = UISearchBar()
    private var isSearchBarVisible = false
    
    // Rest of your existing code...
}

2. Set Up Navigation Bar Toggle Button & Search Bar #

In viewDidLoad, configure the nav bar button to trigger the show/hide action and set up the search bar's initial state:

override func viewDidLoad() {
    super.viewDidLoad()
    
    // Add toggle button to navigation bar
    let toggleSearchButton = UIBarButtonItem(title: "Search", style: .plain, target: self, action: #selector(toggleSearchBarVisibility))
    navigationItem.rightBarButtonItem = toggleSearchButton
    
    // Configure search bar appearance and behavior
    searchBar.placeholder = "Search your items..."
    searchBar.sizeToFit()
    searchBar.delegate = self // Assign delegate if you need to handle search events
    
    // Initial state: hide the search bar
    searchBar.isHidden = true
}

3. Implement Toggle Functionality #

Add the selector method to switch the search bar's visibility and refresh the table view section to reflect the change:

@objc private func toggleSearchBarVisibility() {
    isSearchBarVisible.toggle()
    searchBar.isHidden = !isSearchBarVisible
    
    // Refresh the first section to update header height and visibility
    tableView.reloadSections(IndexSet(integer: 0), with: .automatic)
}

4. Make the Search Bar Sticky & Control Header Height #

Override these table view delegate methods to ensure the search bar stays visible during scrolling (works with plain-style table views) and adjusts the header height based on visibility:

override func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {
    // Return 0 height when search bar is hidden to avoid empty space
    return isSearchBarVisible ? searchBar.frame.height : 0
}

override func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
    // Return the search bar as the section header
    return searchBar
}

Key Notes #

• Sticky Header Requirement: Ensure your table view uses the Plain style (not Grouped) in the storyboard or via code (UITableView(frame: .zero, style: .plain)). Grouped table views don't support sticky section headers.
• Search Functionality: If you need to handle search queries, implement the UISearchBarDelegate methods like searchBar(_:textDidChange:) to filter your table data.
• Customization: You can adjust the search bar's style (e.g., searchBar.searchBarStyle = .minimal) or add a background view to the header for better visual integration.

内容的提问来源于stack exchange，提问作者TakeYourMark