The to-do list is done. You can now finally go and take a break. Just as you reach to turn off the desk lamp, the paw of the boss stops you. He has another little thing he wants you to do.
Meow! You need to program an instant messaging app. It must have the following functionality:
- The message template is in the template tag with the message-template ID.
- The new message is added to the end of the container with the chat-content class.
- To add a new message, you need to enter text in the input field (an element with the chat-form-input class) and click the “Submit” button (which sends data from the form with the chat-form class).
- The message block (with the chat-message class) must contain the message text, a delete button, and a username.
- To delete the message, you need to click the cross button (an element with the chat-message-button class). This button appears when you hover the mouse over a message.
If you can complete this assignment, then I will let you take a vacation!
When you are ready, press the Boss, here’s your program! button. Tests will be launched that verify your solution.
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</script><link rel="stylesheet" href="https://assets.htmlacademy.org/css/core.v284.css"><link rel="stylesheet" href="https://assets.htmlacademy.org/css/text.v104.css"><link rel="stylesheet" href="https://assets.htmlacademy.org/css/course-paywall.v6.css"><link rel="stylesheet" href="https://assets.htmlacademy.org/css/course-interface-light.v20.css"><link rel="stylesheet" href="https://assets.htmlacademy.org/css/course-interface-ru.v2.css"><link rel="stylesheet" href="/css/custom.css"><link rel="stylesheet" href="/css/cookies.css"><link rel="preload" as="script" href="https://assets.htmlacademy.org/js/general.v274.js"><title>The third program: “Instant messenger” — Working with DOM — HTML Academy</title><meta name="csrf-token" content=""><meta property="og:type" content="website"><meta property="og:site_name" content="HTML Academy"><meta name="twitter:url" property="og:url" content="https://htmlacademy.org"><meta name="twitter:title" property="og:title" content="Interactive online courses HTML Academy"><meta name="twitter:description" property="og:description" content="Together we’ll learn how to work with real code, solve true-to-life problems, use cutting edge technologies. Minimum of boring theory and lots of practical tasks."><meta name="twitter:image" property="og:image" content="https://htmlacademy.org/og/htmlacademy.png"><meta name="twitter:card" content="summary_large_image"><link rel="canonical" href="https://htmlacademy.org/courses/javascript-browser/dom/instant-messanger"><meta name="theme-color" content="#2f358f"></head><body class="course-interface course-interface--light" data-base="/assets/courses/31/"><header class="page-header page-header--course"><div class="page-header__inner"><div class="page-header__top"><a class="page-header__logo" href="/" aria-label="HTML Academy Home"><img src="https://assets.htmlacademy.org/img/logo--small.svg?cs=1218aec0be4a5f23db79ad29a14e30f7f9fb9a25" width="24" height="36" alt="HTML Academy"></a><nav class="main-nav main-nav--mini" role="navigation"><div class="main-nav__course-nav"><a class="main-nav__course-item main-nav__course-button main-nav__course-button--prev" href="/courses/javascript-browser/dom/summary">Summary of “Actions with DOM”</a><div class="main-nav__course-item main-nav__course-list main-nav__course-list--collapsed"><b class="main-nav__course-title">Working with DOM</b><span class="main-nav__course-stat">23/23</span><div class="main-nav__course-contents"><a class="main-nav__course-contents-link" href="/courses/javascript-browser/dom">Back to the list of tasks</a><ul class="main-nav__course-contents-list"><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/to-do-list">1. What are you planning to do?</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/change-event">2. The “change” event</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/change-event-2">3. How the “change” event works</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/delete-element">4. Deleting the element from the list</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/check-collection-length">5. How to check the collection length</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/debug-code">6. Debugging the code</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/static-live-collection">7. Static and live collections</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/display-message">8. Displaying the message on the page</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/submit-event">9. The “submit” event</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/cancel-form-submit">10. Cancelling the form submission</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/obtain-text-input">11. How to obtain text from the input field</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/template-tag">12. Templates and the <template> tag</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/document-fragment">13. The contents of the <template> tag, document-fragment</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/clone-element">14. Cloning and inserting elements, part 1</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/clone-element-2">15. Cloning and inserting elements, part 2</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/clone-element-3">16. Cloning and inserting elements, part 3</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/clone-element-4">17. Cloning and inserting elements, part 4</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/clone-element-5">18. How to clone elements</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/add-new-element">19. Adding a new element to a list</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/delete-new-task">20. Deleting a new task in the list</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/clear-input">21. Clearing the input field</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-browser/dom/summary">22. Summary of “Actions with DOM”</a></li><li class="main-nav__course-contents-item main-nav__course-contents-item--current"><a href="/courses/javascript-browser/dom/instant-messanger">23. The third program: “Instant messenger”</a></li></ul></div></div><a class="main-nav__course-item main-nav__course-button main-nav__course-button--next" href="/courses/javascript-browser/dom">List of tasks</a></div><ul class="main-nav__list main-nav__list--user main-nav__list--user-guest"><li class="main-nav__item" itemprop="name"><a class="main-nav__link" href="/signup?redirect_url=%2Fcourses%2Fjavascript-browser%2Fdom%2Finstant-messanger" title="Sign up" data-modal="open" data-value="register" itemprop="url"><span class="main-nav__icon" aria-hidden="true"><svg aria-hidden="true"><use xlink:href="/img/sprites/general.svg#user"></use></svg></span>Sign up</a></li><li class="main-nav__item main-nav__item--login" itemprop="name"><a class="main-nav__link" href="/login?redirect_url=%2Fcourses%2Fjavascript-browser%2Fdom%2Finstant-messanger" title="Log in" data-modal="open" data-value="login" itemprop="url"><span class="main-nav__icon" aria-hidden="true"><svg aria-hidden="true"><use xlink:href="/img/sprites/general.svg#login"></use></svg></span>Log in</a></li></ul></nav></div></div></header><main class="course-container course-interface__content js-course"><div class="course-container__inner"><article class="course-layout"><div class="course-layout__sidebar course-theory"><div class="course-theory__inner course-theory__inner--left-stub"><button class="course-theory__close icon-close icon-close--light" type="button" title="Close">Close</button><ul class="course-tabs course-tabs--non-interactive course-layout__theory-heading"><li class="course-tabs__item course-tabs__item--external course-tab course-tab--centered"><span class="course-tab__icon"><svg aria-hidden="true"><use xlink:href="courses#icon-theory"></use></svg></span><span class="course-tab__title">Theory</span></li><li class="course-tabs__item course-tabs__item--internal course-tab course-tab--centered course-tab--active"><span class="course-tab__icon"><svg aria-hidden="true"><use xlink:href="courses#icon-theory"></use></svg></span><span class="course-tab__title">Theory</span></li></ul><section class="course-theory__content"><div class="course-theory__content-inner"><h1 class="course-theory__content-heading">The third program: “Instant messenger”</h1><div class="course-theory__content-text"><p>The to-do list is done. You can now finally go and take a break. Just as you reach to turn off the desk lamp, the paw of the boss stops you. He has another little thing he wants you to do.</p><blockquote><p>Meow! You need to program an instant messaging app. It must have the following functionality:</p><ul><li>The message template is in the <code>template</code> tag with the <code class="nowrap">message-template</code> ID.</li><li>The new message is added to the end of the container with the <code class="nowrap">chat-content</code> class.</li><li>To add a new message, you need to enter text in the input field (an element with the <code class="nowrap">chat-form-input</code> class) and click the “Submit” button (which sends data from the form with the <code class="nowrap">chat-form</code> class).</li><li>The message block (with the <code class="nowrap">chat-message</code> class) must contain the message text, a delete button, and a username.</li><li>To delete the message, you need to click the cross button (an element with the <code class="nowrap">chat-message-button</code> class). This button appears when you hover the mouse over a message.</li></ul><p>If you can complete this assignment, then I will let you take a vacation!</p></blockquote><p>When you are ready, press the <span class="course-theory__example-button">Boss, here’s your program!</span> button. 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