153 lines
3.2 KiB
Markdown
153 lines
3.2 KiB
Markdown
---
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id: 587d7fad367417b2b2512be1
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title: Handle Click Events with JavaScript using the onclick property
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challengeType: 6
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forumTopicId: 301503
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---
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## Description
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<section id='description'>
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You want your code to execute only once your page has finished loading. For that purpose, you can attach a JavaScript event to the document called <code>DOMContentLoaded</code>. Here's the code that does this:
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```js
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document.addEventListener('DOMContentLoaded', function() {
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});
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```
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You can implement event handlers that go inside of the <code>DOMContentLoaded</code> function. You can implement an <code>onclick</code> event handler which triggers when the user clicks on the element with id <code>getMessage</code>, by adding the following code:
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```js
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document.getElementById('getMessage').onclick = function(){};
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```
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</section>
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## Instructions
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<section id='instructions'>
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Add a click event handler inside of the <code>DOMContentLoaded</code> function for the element with id of <code>getMessage</code>.
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: Your code should use the <code>document.getElementById</code> method to select the <code>getMessage</code> element.
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testString: assert(code.match(/document\s*\.getElementById\(\s*?('|")getMessage\1\s*?\)/g));
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- text: Your code should add an <code>onclick</code> event handler.
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testString: assert(typeof document.getElementById('getMessage').onclick === 'function');
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='html-seed'>
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```html
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<script>
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document.addEventListener('DOMContentLoaded', function(){
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// Add your code below this line
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// Add your code above this line
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});
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</script>
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<style>
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body {
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text-align: center;
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font-family: "Helvetica", sans-serif;
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}
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h1 {
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font-size: 2em;
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font-weight: bold;
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}
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.box {
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border-radius: 5px;
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background-color: #eee;
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padding: 20px 5px;
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}
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button {
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color: white;
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background-color: #4791d0;
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border-radius: 5px;
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border: 1px solid #4791d0;
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padding: 5px 10px 8px 10px;
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}
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button:hover {
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background-color: #0F5897;
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border: 1px solid #0F5897;
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}
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</style>
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<h1>Cat Photo Finder</h1>
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<p class="message box">
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The message will go here
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</p>
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<p>
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<button id="getMessage">
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Get Message
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</button>
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</p>
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```html
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<script>
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document.addEventListener('DOMContentLoaded', function(){
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// Add your code below this line
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document.getElementById('getMessage').onclick = function(){ };
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// Add your code above this line
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});
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</script>
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<style>
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body {
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text-align: center;
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font-family: "Helvetica", sans-serif;
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}
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h1 {
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font-size: 2em;
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font-weight: bold;
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}
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.box {
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border-radius: 5px;
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background-color: #eee;
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padding: 20px 5px;
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}
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button {
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color: white;
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background-color: #4791d0;
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border-radius: 5px;
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border: 1px solid #4791d0;
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padding: 5px 10px 8px 10px;
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}
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button:hover {
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background-color: #0F5897;
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border: 1px solid #0F5897;
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}
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</style>
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<h1>Cat Photo Finder</h1>
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<p class="message box">
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The message will go here
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</p>
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<p>
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<button id="getMessage">
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Get Message
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</button>
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</p>
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```
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</section>
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