如何通过编程调用TextView中的「查找建议」（Siri搜索建议）功能？

Hey there! Great question—this is totally doable on iOS using Apple's native APIs. I've implemented something similar before, so let me walk you through how to pull it off:

前提说明 #

First off, this is an iOS-specific system feature, so all examples below use Swift and iOS SDK APIs.

Step 1: Capture the Selected Text #

First, you need to grab the highlighted text from your UITextView—either what the user has selected, or a range you programmatically set:

guard let selectedRange = textView.selectedTextRange,
      let lookupText = textView.text(in: selectedRange) else {
    // No text selected, exit early
    return
}

Step 2: Trigger the System "Look Up" Interface #

There are two solid ways to launch the native look-up experience (including Siri search suggestions, dictionary definitions, and web results):

Option 1: Use UIReferenceLibraryViewController (Official, Public API)

This is Apple's recommended way to show the system look-up UI. It handles dictionary definitions first, and falls back to broader search if needed:

let lookupVC = UIReferenceLibraryViewController(term: lookupText)

// Check if the term has a dictionary definition first
if UIReferenceLibraryViewController.dictionaryHasDefinition(forTerm: lookupText) {
    present(lookupVC, animated: true)
} else {
    // If no dictionary entry exists, trigger system-wide search via URL scheme
    guard let encodedText = lookupText.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed),
          let searchURL = URL(string: "x-apple-data-detectors://?type=look-up&query=\(encodedText)") else {
        return
    }
    
    if UIApplication.shared.canOpenURL(searchURL) {
        UIApplication.shared.open(searchURL, options: [:], completionHandler: nil)
    }
}

Option 2: Add a Custom "Look Up" Menu Item

If you want to replicate the exact flow where users highlight text and tap a "Look Up" option (just like the native TextView), you can add a custom menu item to the text view's interaction menu:

override func viewDidLoad() {
    super.viewDidLoad()
    
    // Create and add the custom menu item
    let lookUpItem = UIMenuItem(title: "Look Up", action: #selector(handleLookUpTapped))
    UIMenuController.shared.menuItems = [lookUpItem]
    
    // Ensure the text view can accept user interaction
    textView.isUserInteractionEnabled = true
    textView.becomeFirstResponder()
}

@objc private func handleLookUpTapped() {
    // Reuse the text capture and lookup logic from Step 1 & Option 1
    guard let selectedRange = textView.selectedTextRange,
          let lookupText = textView.text(in: selectedRange) else {
        return
    }
    
    let lookupVC = UIReferenceLibraryViewController(term: lookupText)
    if UIReferenceLibraryViewController.dictionaryHasDefinition(forTerm: lookupText) {
        present(lookupVC, animated: true)
    } else {
        guard let encodedText = lookupText.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed),
              let searchURL = URL(string: "x-apple-data-detectors://?type=look-up&query=\(encodedText)") else {
            return
        }
        
        if UIApplication.shared.canOpenURL(searchURL) {
            UIApplication.shared.open(searchURL, options: [:], completionHandler: nil)
        }
    }
}

Key Notes #

• The x-apple-data-detectors URL scheme is a native iOS way to trigger system-wide look-up, which includes Siri's search suggestions for non-dictionary terms.
• Make sure your app has network access enabled if you want to load online results (like web suggestions or Siri data)—most apps already have this enabled by default.
• For macOS with NSTextView, the logic is similar but uses NSReferenceLibraryViewController instead.

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