# web dev **URL:** https://forum.kirupa.com/c/programming/web-dev/42.md?page=34 [Latest](https://forum.kirupa.com/latest.md) · [Categories](https://forum.kirupa.com/categories.md) **Page:** 35 --- ## [JS Tip of the Day: Optional Chaining](https://forum.kirupa.com/t/js-tip-of-the-day-optional-chaining/643182)
**Author:** [@senocular](https://forum.kirupa.com/u/senocular)\ **Replies:** 0\ **Last updated:** [February 14, 2020, 10:10pm UTC](https://forum.kirupa.com/t/js-tip-of-the-day-optional-chaining/643182 "2020-02-14T22:10:20Z")
--- ## [JavaScript Tips of the Day](https://forum.kirupa.com/t/javascript-tips-of-the-day/641803)
**Author:** [@senocular](https://forum.kirupa.com/u/senocular)\ **Replies:** 0\ **Last updated:** [February 14, 2020, 10:08pm UTC](https://forum.kirupa.com/t/javascript-tips-of-the-day/641803 "2020-02-14T22:08:43Z")
Here, you’ll find tips posted daily relating to JavaScript: its features, how its used, and anything else related to the language and developing with it. Tips Latest ES2021 Preview Async Generators The Long Arrow Oper… --- ## [Pulsing Circles (CSS Animation)](https://forum.kirupa.com/t/pulsing-circles-css-animation/638202)
**Author:** [@kirupa](https://forum.kirupa.com/u/kirupa)\ **Replies:** 6\ **Last updated:** [February 13, 2020, 9:16pm UTC](https://forum.kirupa.com/t/pulsing-circles-css-animation/638202 "2020-02-13T21:16:02Z")
Just a little example I created to highlight a pulsing effect: https://www.kirupa.com/animations/examples/pulsing\_circle.html The full markup looks as follows: \ \ \ \ **Author:** [@HILAL\_KEKEC](https://forum.kirupa.com/u/HILAL_KEKEC)\ **Replies:** 0\ **Last updated:** [January 17, 2020, 6:51am UTC](https://forum.kirupa.com/t/dragging-items-between-lists/641615 "2020-01-17T06:51:41Z") --- ## [Pure CSS Galley Carousel with Keypress?](https://forum.kirupa.com/t/pure-css-galley-carousel-with-keypress/641469)
**Author:** [@4a0g1kfa54](https://forum.kirupa.com/u/4a0g1kfa54)\ **Replies:** 1\ **Last updated:** [December 30, 2019, 5:12pm UTC](https://forum.kirupa.com/t/pure-css-galley-carousel-with-keypress/641469 "2019-12-30T17:12:35Z")
Hi I have a pure css carousel lightbox which is working fine. However, I would like to do three things: -when i press ESC it simulates clicking the close button; -when pressing left and right it simulates clicking the… --- ## [Parallax](https://forum.kirupa.com/t/parallax/634974)
**Author:** [@VaiFanatic](https://forum.kirupa.com/u/VaiFanatic)\ **Replies:** 8\ **Last updated:** [July 29, 2016, 5:24am UTC](https://forum.kirupa.com/t/parallax/634974 "2016-07-29T05:24:19Z")
I'm creating a parallax website (using an older standard of jQuery to perform the sliding animation from the nav bar) and I'm having an issue setting the first "slide" to be max height regardless of resolution. Here's … --- ## [How to make an object face the mouse in Canvas?](https://forum.kirupa.com/t/how-to-make-an-object-face-the-mouse-in-canvas/641330)
**Author:** [@brilliant](https://forum.kirupa.com/u/brilliant)\ **Replies:** 5\ **Last updated:** [December 17, 2019, 10:41am UTC](https://forum.kirupa.com/t/how-to-make-an-object-face-the-mouse-in-canvas/641330 "2019-12-17T10:41:51Z")
Hello there. I am wondering how to make an object rotate to face the current position of the mouse in a canvas. I am not sure if this is a question yet but I am keen to knowing how to do this. For example, in agar.io, y… --- ## [PEBKACC Time!](https://forum.kirupa.com/t/pebkacc-time/641268)
**Author:** [@kirupa](https://forum.kirupa.com/u/kirupa)\ **Replies:** 3\ **Last updated:** [December 8, 2019, 4:02pm UTC](https://forum.kirupa.com/t/pebkacc-time/641268 "2019-12-08T16:02:54Z")
PEBKAC is now…PEBKACC: Problem exists between keyboard, cat, and chair! :stuck\_out\_tongue: --- ## [XML/XSL for view& print -- pro or con?](https://forum.kirupa.com/t/xml-xsl-for-view-print-pro-or-con/641230)
**Author:** [@gNeandr](https://forum.kirupa.com/u/gNeandr)\ **Replies:** 3\ **Last updated:** [December 8, 2019, 8:13am UTC](https://forum.kirupa.com/t/xml-xsl-for-view-print-pro-or-con/641230 "2019-12-08T08:13:20Z")
What is the experience to use XML/XSL as View & Print Generator? Is the use of XSLTProcessor future-proof? The main focus is the use in Firefox/Chrome. --- ## [I made an open-source toolkit for developing with HTML, CSS, and JS.](https://forum.kirupa.com/t/i-made-an-open-source-toolkit-for-developing-with-html-css-and-js/640996)
**Author:** [@grayshift](https://forum.kirupa.com/u/grayshift)\ **Replies:** 1\ **Last updated:** [December 7, 2019, 11:35am UTC](https://forum.kirupa.com/t/i-made-an-open-source-toolkit-for-developing-with-html-css-and-js/640996 "2019-12-07T11:35:47Z")
Hi guys, I made an open-source toolkit for developing with HTML, CSS, and JS that I would like to share with you. Components GitHub repository --- ## [I keep getting an error while using react router, please anyone guide me what's the possible solution for this](https://forum.kirupa.com/t/i-keep-getting-an-error-while-using-react-router-please-anyone-guide-me-whats-the-possible-solution-for-this/641236)
**Author:** [@Ghouse\_Shaik](https://forum.kirupa.com/u/Ghouse_Shaik)\ **Replies:** 1\ **Last updated:** [December 7, 2019, 11:27am UTC](https://forum.kirupa.com/t/i-keep-getting-an-error-while-using-react-router-please-anyone-guide-me-whats-the-possible-solution-for-this/641236 "2019-12-07T11:27:04Z")
react.js:20478 Warning: React.createElement: type should not be null, undefined, boolean, or number. It should be a string (for DOM elements) or a ReactClass (for composite components). printWarning @ react.js:20478 wa… --- ## [Learning React - urls in chapter 11 donlt work](https://forum.kirupa.com/t/learning-react-urls-in-chapter-11-donlt-work/641091)
**Author:** [@grobbins](https://forum.kirupa.com/u/grobbins)\ **Replies:** 2\ **Last updated:** [November 17, 2019, 10:48pm UTC](https://forum.kirupa.com/t/learning-react-urls-in-chapter-11-donlt-work/641091 "2019-11-17T22:48:17Z")
The following urls in the second editoin of the Learning React book in chapter 11 do not work https://www.kirupa.com/react/ lifecycle\_example.htm Please provide the correct URLS --- ## [Codes not working](https://forum.kirupa.com/t/codes-not-working/640070)
**Author:** [@Ramzy\_Phailin](https://forum.kirupa.com/u/Ramzy_Phailin)\ **Replies:** 3\ **Last updated:** [November 12, 2019, 8:49pm UTC](https://forum.kirupa.com/t/codes-not-working/640070 "2019-11-12T20:49:19Z")
Hi I’ve been practised from the Learn React: Hands-On Guide to Building Web Applications Using React and Redux (2nd Edition). I am currently viewing the chapter 3 on the component. When I try to follow through and see t… --- ## [Using the Cache Api with only a web worker](https://forum.kirupa.com/t/using-the-cache-api-with-only-a-web-worker/640979)
**Author:** [@bstagy](https://forum.kirupa.com/u/bstagy)\ **Replies:** 3\ **Last updated:** [November 8, 2019, 4:31am UTC](https://forum.kirupa.com/t/using-the-cache-api-with-only-a-web-worker/640979 "2019-11-08T04:31:15Z")
Hi, I’m new to PWA’s and am working on my first one. I’m at the point where decisions have to be made on storage. I understand to use a service worker in say, Heroku, you have to have an SSL certificate. And to have a… --- ## [Hiding File Input UI](https://forum.kirupa.com/t/hiding-file-input-ui/640953)
**Author:** [@clo](https://forum.kirupa.com/u/clo)\ **Replies:** 1\ **Last updated:** [October 29, 2019, 12:51pm UTC](https://forum.kirupa.com/t/hiding-file-input-ui/640953 "2019-10-29T12:51:26Z")
I wanted to overwrite the typical “Choose file” button of the \ and got the below code to hide the standard and replace it with a Semantic-UI \. However, I realised in hiding the original input button, I als… --- ## [how to make nth-child include a range (eg. 0-19)](https://forum.kirupa.com/t/how-to-make-nth-child-include-a-range-eg-0-19/640927)
**Author:** [@4a0g1kfa54](https://forum.kirupa.com/u/4a0g1kfa54)\ **Replies:** 10\ **Last updated:** [October 28, 2019, 1:26pm UTC](https://forum.kirupa.com/t/how-to-make-nth-child-include-a-range-eg-0-19/640927 "2019-10-28T13:26:42Z")
hi all, I have a bit of css code and each div child needs to have a property. Hence it looks like this. It goes from 0 all the way to 19. div:nth-child(0) { transform: translate3D(0%, 0%, calc(var(--itemZ) \* var(--cam… --- ## [Research survey in web development](https://forum.kirupa.com/t/research-survey-in-web-development/640877)
**Author:** [@iResearch](https://forum.kirupa.com/u/iResearch)\ **Replies:** 2\ **Last updated:** [October 28, 2019, 12:32pm UTC](https://forum.kirupa.com/t/research-survey-in-web-development/640877 "2019-10-28T12:32:40Z")
Hi, At the Information Security and Privacy Lab at the University of Lausanne (https://isplab.unil.ch), we are conducting research on web development practices. This survey is for web developers. Completing the survey… --- ## [Wordpress plugin revslider issue to update the PHP Version](https://forum.kirupa.com/t/wordpress-plugin-revslider-issue-to-update-the-php-version/640885)
**Author:** [@nuzzledot](https://forum.kirupa.com/u/nuzzledot)\ **Replies:** 0\ **Last updated:** [October 18, 2019, 11:40am UTC](https://forum.kirupa.com/t/wordpress-plugin-revslider-issue-to-update-the-php-version/640885 "2019-10-18T11:40:48Z")
Hello my site run on the PHP version 5.6 but when i have update the PHP version 7.0 the site is not working it will be showing white page only. I have enable debug log and check that revslider plugin not working in the… --- ## [List Items Vertically Spaced Evenly Within a Flexbox Container](https://forum.kirupa.com/t/list-items-vertically-spaced-evenly-within-a-flexbox-container/640131)
**Author:** [@AurturoJane](https://forum.kirupa.com/u/AurturoJane)\ **Replies:** 1\ **Last updated:** [August 6, 2019, 1:44pm UTC](https://forum.kirupa.com/t/list-items-vertically-spaced-evenly-within-a-flexbox-container/640131 "2019-08-06T13:44:30Z")
Alright guys, I’m learning CSS right now, and I’m kind of stumped as to why I can’t get it to do what I want it to do. It’s probably something extremely simple that I’m overlooking. I’m wanting to have an unordered list… --- ## [loading page issues](https://forum.kirupa.com/t/loading-page-issues/640580)
**Author:** [@fpiera](https://forum.kirupa.com/u/fpiera)\ **Replies:** 1\ **Last updated:** [September 22, 2019, 2:21pm UTC](https://forum.kirupa.com/t/loading-page-issues/640580 "2019-09-22T14:21:25Z")
Hi, I hope you can help with this issue. Iam not full skilled with JS. Recently I followed the video “Creating a Smooth Sliding Menu” and every seems to work fine until the page is reloaded. The “sliding menu” is always… --- ## [Picking Random Item in a Multi-dimensional Array](https://forum.kirupa.com/t/picking-random-item-in-a-multi-dimensional-array/640802)
**Author:** [@v\_vendetta](https://forum.kirupa.com/u/v_vendetta)\ **Replies:** 5\ **Last updated:** [October 10, 2019, 5:35pm UTC](https://forum.kirupa.com/t/picking-random-item-in-a-multi-dimensional-array/640802 "2019-10-10T17:35:50Z")
--- ## [Style with js](https://forum.kirupa.com/t/style-with-js/640823)
**Author:** [@Rajesh\_Pardhan](https://forum.kirupa.com/u/Rajesh_Pardhan)\ **Replies:** 0\ **Last updated:** [October 12, 2019, 3:22pm UTC](https://forum.kirupa.com/t/style-with-js/640823 "2019-10-12T15:22:23Z")
Dear jeeks please convert following css to js. And… / or… how to use css var in this code? @keyframes example { from { transform: rotate(var(--rotateDeg)); } to { transform: rotate(360deg); } --- ## [Help me improve my site](https://forum.kirupa.com/t/help-me-improve-my-site/640471)
**Author:** [@DianeLeanne](https://forum.kirupa.com/u/DianeLeanne)\ **Replies:** 2\ **Last updated:** [September 13, 2019, 5:07am UTC](https://forum.kirupa.com/t/help-me-improve-my-site/640471 "2019-09-13T05:07:53Z")
Hello everyone! I am new to this community so I would like to apologize on my question. I am an entrepreneur as of the moment, but because technology evolves I am now learning web development. Horay! I am working with a… --- ## [Nested Modals. Issue with Closing Modals.](https://forum.kirupa.com/t/nested-modals-issue-with-closing-modals/640684)
**Author:** [@4a0g1kfa54](https://forum.kirupa.com/u/4a0g1kfa54)\ **Replies:** 5\ **Last updated:** [October 8, 2019, 4:59am UTC](https://forum.kirupa.com/t/nested-modals-issue-with-closing-modals/640684 "2019-10-08T04:59:08Z")
Hi all, I am trying to add some functionality to this setup. As you will see, it is an attempt to make a nested modal setup, that on every click on a modal link, it recedes and blurs everything behind the modal. I hav… --- ## [JavaScript's global object is now "globalThis"](https://forum.kirupa.com/t/javascripts-global-object-is-now-globalthis/638917)
**Author:** [@senocular](https://forum.kirupa.com/u/senocular)\ **Replies:** 8\ **Last updated:** [October 5, 2019, 1:31am UTC](https://forum.kirupa.com/t/javascripts-global-object-is-now-globalthis/638917 "2019-10-05T01:31:54Z")
Just noticed the name change today. Too much breaking the web :roll\_eyes: by using just global so we’re left with globalThis (still stage 3 but almost there). My first impression on the naming… --- ## [Adding Search function to Isotope's "hideReveal" plugin](https://forum.kirupa.com/t/adding-search-function-to-isotopes-hidereveal-plugin/640664)
**Author:** [@4a0g1kfa54](https://forum.kirupa.com/u/4a0g1kfa54)\ **Replies:** 2\ **Last updated:** [September 29, 2019, 4:12pm UTC](https://forum.kirupa.com/t/adding-search-function-to-isotopes-hidereveal-plugin/640664 "2019-09-29T16:12:28Z")
Hi all, I’ve adapted some code from Desandro’s “hideReveal” plugin for Isotope: https://codepen.io/desandro/pen/drpJK/ But I am trying to add a search functionality to it, and I am having some trouble. Could someone he… --- ## [Moving function from outside to inside](https://forum.kirupa.com/t/moving-function-from-outside-to-inside/640440)
**Author:** [@clo](https://forum.kirupa.com/u/clo)\ **Replies:** 2\ **Last updated:** [September 9, 2019, 9:08pm UTC](https://forum.kirupa.com/t/moving-function-from-outside-to-inside/640440 "2019-09-09T21:08:01Z")
I have this function working outside of the class App extends Component, but I want to move it inside since I can’t call an inner function from the outside: function moveToSelection(selected){ for(let indexPat… --- ## [Button onclick disables draggable ??](https://forum.kirupa.com/t/button-onclick-disables-draggable/640149)
**Author:** [@vmars316](https://forum.kirupa.com/u/vmars316)\ **Replies:** 5\ **Last updated:** [August 8, 2019, 11:34pm UTC](https://forum.kirupa.com/t/button-onclick-disables-draggable/640149 "2019-08-08T23:34:18Z")
Hello & Thanks :slight\_smile: In the code below: Draggable works great until I click the Button . Then ’ elmnt.cloneNode ’ doesn’t work and then draggable stops working . I tried to run code in DeveloperTools , but … --- ## [Yet another grid in IE conundrum](https://forum.kirupa.com/t/yet-another-grid-in-ie-conundrum/640221)
**Author:** [@rcsflangton](https://forum.kirupa.com/u/rcsflangton)\ **Replies:** 2\ **Last updated:** [August 20, 2019, 2:55pm UTC](https://forum.kirupa.com/t/yet-another-grid-in-ie-conundrum/640221 "2019-08-20T14:55:52Z")
Greetings. I am taking this question to this forum because 1) there seem to be some Windows smarts here, and 2) Kirupa’s advice on handling CSS has been among the most cogent I’ve found on the Web, recently. The questi… --- ## [XMLHttpRequest() .status code 429](https://forum.kirupa.com/t/xmlhttprequest-status-code-429/640055)
**Author:** [@sirgil2009](https://forum.kirupa.com/u/sirgil2009)\ **Replies:** 5\ **Last updated:** [August 16, 2019, 4:36pm UTC](https://forum.kirupa.com/t/xmlhttprequest-status-code-429/640055 "2019-08-16T16:36:47Z")
I have written some React code that makes a single Http request to a site. I keep getting a 429 response code indicating my code is sending too many requests to the server. The code is only making one XMLHttpRequest;… [Previous page](https://forum.kirupa.com/c/programming/web-dev/42.md?page=33) [Next page](https://forum.kirupa.com/c/programming/web-dev/42.md?page=35)