Practice Set, Week 9, Event Handling and Bubbling
by rachelmc_
HTML
<h3>Practice Set, Week 9, Event Handling and Bubbling</h3>
<p>This page contains two buttons, each with an event handler that causes the button, when clicked to echo its text to the page.</p>
<p>Your task is to rewrite the event handling code so that there is only one event handling function. That function should be called when a user clicks on <i>either</i> button. The output should remain identical. </p>
<p>You'll want to consider attaching a single event handler to a node further up the DOM tree, and checking there for which element was actually clicked (using a conditional). </p>
<p>Hint: this is exactly the process that's demonstrated in the video in Week 9 Lesson 2</p>
<div id="container">
<h4 id="output"></h4>
<button id="happyBtn">Coding can be fun!</button>
<button id="gloomyBtn">Coding can be maddening!</button>
</div>
CSS
.button {
text-indent:0;
border:1px solid #eda933;
display:inline-block;
color:#ffffff;
font-family:Arial;
font-size:15px;
font-weight:bold;
font-style:normal;
height:65px;
line-height:65px;
padding: .5 em;
text-decoration:none;
text-align:center;
text-shadow:1px 1px 0px #cd8a15;
background-color:#f6b33d;
}
JavaScript
//This button will give you the link to
var happy = document.getElementById("happyBtn");
happy.addEventListener("click", function(evt){
logMessage(evt.currentTarget.innerHTML);
});
var gloomy = document.getElementById("gloomyBtn");
gloomy.addEventListener("click", function(evt){
logMessage(evt.currentTarget.innerHTML);
});
// Utility function for logging convenience
// Logs msg to the element with given id
// If id is undefined, logs to #output
function logMessage(msg, id){
if (!id){
id="output";
}
document.getElementById(id).innerHTML += msg + "<br>";
}