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Popstate on page's load in Chrome

javascript
prompt-engineering
best-practices
state-management
Nikita BarsukovbyNikita BarsukovยทOct 2, 2024
โšกTLDR

Circumvent Chrome's unexpected popstate event firing on page load, by using a simple flag to differentiate between a user-initiated navigation and an automated one. Nest this logic within window event listeners for load and popstate. Here's a short example which encapsulates our approach:

let userNavigated = false; window.addEventListener('load', () => { // Update the URL without reloading, because we're cool like that ๐Ÿ˜Ž history.pushState(null, null, window.location.href); }); window.addEventListener('popstate', () => { if (userNavigated) { // Your popstate logic here // ๐ŸŽ‰ It's a party every time the user navigates! ๐ŸŽ‰ console.log('User navigated!'); } userNavigated = true; // Give Chrome a high-five after its first popstate! });

Note: We initially set userNavigated as false and switch it to true only after Chrome's first popstate event. This guarantees that your popstate code runs purely for legitimate navigation events.

Decoding Browser Differences

Working with popstate event typically opens a Pandora's box of deviant behaviors. Let's walk through the aberrations:

Firefox's Discipline: In a disciplined contrast to Chrome, Firefox doesn't fire the popstate event right at page load.

Chrome's Whims: Chrome's unpredictable behavior with popstate also films a chronicle of evolution. For example, starting from Chrome 19, an additional check window.history.state !== null needs to be issued to handle the initial page load correctly.

Multi-Browser Validation: A comprehensive cross-browser testing isn't optional. Make sure to test your solution against all major browsers.

Navigation vs. Refresh: A simple flag variable like userNavigated can help to differentiate between page reloads and actual user navigation.

Embracing Timing: Particularly when using setTimeout as a workaround, take a deep dive into understanding the timing of content loading in order to ensure user experience isn't compromised.

Making Browsers Play Ball

To tackle the popstate quirks, you might consider the following strategies:

Initialising the Ground Rule

Populate the history state object on page load so it's not null. This helps to make a correct call when popstate is triggered.

if (!('state' in window.history) || window.history.state === null) { window.history.replaceState({}, document.title, window.location.href); }

Taming Popstate's Enthusiasm

Implement conditional checks to ignore popstate event on initial page load, effectively making Chrome dance to Firefox's tunes.

Upholding User Navigation

Using setTimeout as a workaround to delay the popstate event's trigger, we can call dibs on acceptable navigation.

setTimeout(() => { window.addEventListener('popstate', () => { /* ... */ }); }, 0);

Libraries: Less is More

While History.js is a great tool to simplify working with the History API, it's sometimes better to adopt specific and minimal solutions for popstate management, effectively cutting down dependency woes.

Let's delve into a practical approach of managing the popstate event's idiosyncrasies:

Strategy to the Rescue

history.pushState(): Modify the browser's location bar without triggering a page reload, but be cautious to avoid firing unnecessary popstate events.

history.replaceState(): Use this method to update the state object without adding to the history stack, thereby preventing onload popstate events.

Browser Button Handling: Rein in the inconsistent behaviors while ensuring that the browser navigation buttons don't bear the brunt of these workarounds.

Proceed with Caution

Blocked Events: Avoid blocking the popstate event beyond the initial load as this can hinder expected browser behaviors.

The Timing Tangle: Time is of the essence, especially when the setTimeout workaround is in play. Consider its impact on user experience.

Beyond Popstate

AJAX + History API: Merge AJAX techniques with the History API to experience seamless page transitions without triggering page reloads.

State Management: How state data, passed into history.pushState() or history.replaceState(), impacts your popstate logic is crucial for efficient state management.