I'm creating a table displayed in HTML with Django. I want to change the number's color to red when the number is negative, and to green when the number is positive. I know I need to use JS for this but I could not make it work. Any help will be greatly appreciated !!
Here is my Django HTML template :
{% load static %}
<link rel="stylesheet" type="text/css" href="{% static 'WalletJournal/style.css' %}" />
<div id="container">
<h1>{{ Transaction.TransactionDateTime }}</h1>
<table>
<tr>
<th>TRANSACTION AMOUNT</th>
<th>BALANCE AFTER TRANSACTION</th>
<th>TRANSACTION COMMENT</th>
</tr><tr>
<div id="TransactionAmount"><td style="font-family:'Arial',serif;font-size:10pt">{{ Transaction.TransactionAmount }}</td></div>
<td style="font-family:'Arial',serif;font-size:10pt">{{ Transaction.BalanceAfterTransaction }}</td>
<td style="color:white">{{ Transaction.TransactionComment }}</td>
<script>
var el = document.getElementById('TransactionAmount');
if(el<0) {
el.addClass += "red";
} else {
el.addClass += "green";
}
</script>
</tr>
</table>
<h2>Feel free to contact me !</h2>
</div>
And the classes I created in my CSS :
.red {
color:#FF0000;
}
.green {
color:#33FF3C;
}
I tried creating some JS code from examples I found around the web but something must be wrong. My goal is to check if the number TransactionAmount is negative or positive, and adjust the color accordingly. I made the TransactionAmount div to be able to use it with getElementById...
<script>
var el = document.getElementById('TransactionAmount');
if(el<0) {
el.addClass += "red";
} else {
el.addClass += "green";
}
</script>
And my number is still gray....
You need to get the textContent of the element to test it's value. And you can use a single class that toggles if it's positive or not. And either use jquery's $.addClass() and $.removeClass() or javascript's classList.add() and classList.remove().
Also as Sujen K. pointed out, you have a tr > div > td for this element, and it should be tr > td > div instead.
var els = document.getElementsByClassName('TransactionAmount');
for (var i = 0; i < els.length; i++) {
var cell = els[i];
if (cell.textContent < 0) {
cell.classList.remove('green')
} else {
cell.classList.add('green');
}
}.TransactionAmount {
color: #FF0000;
}
.TransactionAmount.green {
color: #33FF3C;
}<table>
<tr>
<th>TRANSACTION AMOUNT</th>
<th>BALANCE AFTER TRANSACTION</th>
<th>TRANSACTION COMMENT</th>
</tr>
<tr>
<td style="font-family:'Arial',serif;font-size:10pt"><div class="TransactionAmount">-1</div></td>
<td style="font-family:'Arial',serif;font-size:10pt">{{ Transaction.BalanceAfterTransaction }}</td>
<td style="color:white">{{ Transaction.TransactionComment }}</td>
</tr>
<tr>
<td style="font-family:'Arial',serif;font-size:10pt"><div class="TransactionAmount">0</div></td>
<td style="font-family:'Arial',serif;font-size:10pt">{{ Transaction.BalanceAfterTransaction }}</td>
<td style="color:white">{{ Transaction.TransactionComment }}</td>
</tr>
<tr>
<td style="font-family:'Arial',serif;font-size:10pt"><div class="TransactionAmount">1</div></td>
<td style="font-family:'Arial',serif;font-size:10pt">{{ Transaction.BalanceAfterTransaction }}</td>
<td style="color:white">{{ Transaction.TransactionComment }}</td>
</tr>
</table>There are two problems. The HTML hierarchy should be table > tr > td, and you put div > td. The second problem is addClass. This is from the jQuery library, if you want to use plain JS its possible with className. Try this:
<div id="container">
<h1>{{ Transaction.TransactionDateTime }}</h1>
<table>
<tr>
<th>TRANSACTION AMOUNT</th>
<th>BALANCE AFTER TRANSACTION</th>
<th>TRANSACTION COMMENT</th>
</tr><tr>
<td style="font-family:'Arial',serif;font-size:10pt"><div id="TransactionAmount">{{ Transaction.TransactionAmount }}</div></td>
<td style="font-family:'Arial',serif;font-size:10pt">{{ Transaction.BalanceAfterTransaction }}</td>
<td style="color:white">{{ Transaction.TransactionComment }}</td>
<script>
var el = document.getElementById('TransactionAmount');
if(el<0) {
el.className += "red";
} else {
el.className += "green";
}
</script>
</tr>
</table>
<h2>Feel free to contact me !</h2>