Modern Chrome Web Browser Device (Part 4/4)

This is the final post in a 4-post series about looking inside Chrome and exploring how it parses our code to render a website. In the previous post, we looked at * the renderer process and learned about * the compositor thread. In this post, we'll take a look at how * compose flow provides a smooth user experience for user input.





Part 1

Part 2

Part 3

Part 4 (current)



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document.body.addEventListener('touchstart', event => {
    if (event.target === area) {
        event.preventDefault();
    }
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        event.preventDefault()
    }
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5: -



document.body.addEventListener('pointermove', event => {
    if (event.cancelable) {
        event.preventDefault(); //   
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    }
}, {passive: true});


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#area {
  touch-action: pan-x;
}




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window.addEventListener('pointermove', event => {
    const events = event.getCoalescedEvents();
    for (let event of events) {
        const x = event.pageX;
        const y = event.pageY;
        /*     x  y */
    }
});




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Many thanks to everyone who reviewed early projects in this series, including (but not limited to) Alex Russell , Paul Irish , Meggin Kearney , Eric Bidelman , Mathias Bynens , Addy Osmani , Kinuko Yasuda , Nasko Oskov , and Charlie Reis.



Did you like this episode? If you have any questions or suggestions for future posts, I would love to hear from you in the comments section below or from me on twitter @kosamari .



Part 1

Part 2

Part 3

Part 4 (current)




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