Solving the Infamous “Assertion failure in -[UIApplication _performAfterCATransactionCommitsWithLegacyRunloopObserverBasedTiming:block:]” Error: A Step-by-Step Guide

Are you tired of seeing the dreaded “Assertion failure in -[UIApplication _performAfterCATransactionCommitsWithLegacyRunloopObserverBasedTiming:block:]” error message every time you try to load a WebView in your app? You’re not alone! This frustrating issue has been plaguing developers for years, but fear not, dear reader, for today we’ll embark on a mission to conquer it once and for all.

What’s causing the error?

Before we dive into the solution, let’s take a step back and understand what’s causing this error. The “Assertion failure in -[UIApplication _performAfterCATransactionCommitsWithLegacyRunloopObserverBasedTiming:block:]” error typically occurs when your app attempts to load a WebView, but something goes wrong during the loading process. This can be due to a variety of reasons, including:

• Improperly configured WebView settings
• Conflicting third-party libraries
• Incompatible OS versions
• Memory issues or leaks

In this article, we’ll explore each of these potential causes and provide you with practical solutions to overcome them.

Step 1: Check your WebView settings

The first step in resolving this error is to ensure that your WebView settings are properly configured. Here are some key things to check:

// Make sure you're using the correct WebView framework
import UIKit
import WebKit

class ViewController: UIViewController, WKUIDelegate {

    // Create a WKWebView instance
    let webView: WKWebView = {
        let webView = WKWebView(frame: .zero)
        webView.uiDelegate = self
        return webView
    }()

    // Load your WebView
    override func viewDidLoad() {
        super.viewDidLoad()
        webView.loadHTMLString("This is a test page.", baseURL: nil)
    }
}

In the code snippet above, we’re creating a WKWebView instance and setting its UI delegate to the current view controller. We’re then loading a simple HTML string into the WebView. If you’re using a third-party library to handle your WebView, ensure that it’s properly integrated and configured.

Step 2: Investigate conflicting third-party libraries

Sometimes, conflicting third-party libraries can cause issues with your WebView. To identify if this is the case, try the following:

1. Disable all third-party libraries in your project
2. Try loading your WebView again
3. If the error persists, re-enable each library one by one to identify the culprit

Some common offenders include libraries like React Native, PhoneGap, or Ionic. If you’re using one of these libraries, try updating to the latest version or seeking guidance from their respective communities.

Step 3: Check for OS version compatibility

It’s essential to ensure that your app is compatible with the target OS version. Make sure you’re:

• Testing on a physical device or simulator with the same OS version as your target audience
• Using the correct SDK and deployment targets in your Xcode project

If you’re targeting an older OS version, try updating your project to use the latest SDK and deployment targets. This might resolve any compatibility issues that could be causing the error.

Step 4: Debug memory issues and leaks

Memory issues or leaks can cause your WebView to crash, resulting in the “Assertion failure in -[UIApplication _performAfterCATransactionCommitsWithLegacyRunloopObserverBasedTiming:block:]” error. To identify and resolve memory-related issues:

• Use Instruments to profile your app’s memory usage
• Check for any suspicious memory allocations or leaks
• Implement proper memory management practices in your code

In Instruments, you can use the Allocations and Leaks templates to identify memory issues. By fixing these problems, you might resolve the underlying cause of the error.

Additional troubleshooting steps

If the above steps don’t resolve the issue, try the following:

• Clear your app’s cache and data
• Check for any JavaScript errors in your WebView’s content
• Verify that your WebView is not being deallocated prematurely
• Test your app on different devices or simulators to isolate the problem

By following these steps, you should be able to identify and resolve the underlying cause of the “Assertion failure in -[UIApplication _performAfterCATransactionCommitsWithLegacyRunloopObserverBasedTiming:block:]” error.

Conclusion

Solving the “Assertion failure in -[UIApplication _performAfterCATransactionCommitsWithLegacyRunloopObserverBasedTiming:block:]” error requires patience, persistence, and a systematic approach to debugging. By following the steps outlined in this article, you should be able to identify and resolve the root cause of the issue, ensuring that your app’s WebView loads successfully and provides a seamless user experience.

Causes	Solutions
Improperly configured WebView settings	Check WebView settings and configuration
Conflicting third-party libraries	Identify and resolve library conflicts
Incompatible OS versions	Ensure compatibility with target OS version
Memory issues or leaks	Debug and resolve memory-related issues

Remember, debugging is an art that requires creativity, persistence, and a willingness to learn. Don’t be afraid to experiment, try new approaches, and seek guidance from online communities and forums. With these tools and techniques at your disposal, you’ll be well-equipped to tackle the “Assertion failure in -[UIApplication _performAfterCATransactionCommitsWithLegacyRunloopObserverBasedTiming:block:]” error and provide a seamless user experience for your app’s users.

Frequently Asked Question

Stuck on the annoying “App Crashes loading webview” error? Don’t worry, we’ve got the answers to get you back on track!