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JavaScript AJAX Basics (retiring) AJAX and APIs Call the jQuery $.getJSON method

Justin Estrada
Justin Estrada
34,995 Points
Posted by Justin Estrada
Justin Estrada
34,995 Points

Can anybody see what's wrong with my jQuery ajax $.getJSON() code

Note sure what's wrong

weather.js 
$(document).ready(function() {

  var URL = 'http://api.openweathermap.org/data/2.5/weather';
  var data = {
    q : "Portland,OR",
    units : "metric"
  };
  function showWeather(weatherReport) {
    $('#temperature').text(weatherReport.main.temp);
  }
  jQuery.getJSON(URL, data, showWeather());
});
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>What's the Weather Like?</title>
  <script src="jquery.js"></script>
  <script src="weather.js"></script>
</head>
<body>
  <div id="main">
    <h1>Current temperature: <span id="temperature"></span>&deg;</h1>
  </div>
</body>
</html>

1 Answer

Marcus Parsons
Marcus Parsons
15,719 Points

Hiya Justin,

I'm not sure why you changed the variable names in the challenge, but you shouldn't do that because the challenges look for specific variable/function names. URL should be "weatherAPI". Also, when calling the function in getJSON, you don't use () because it's a reference to the function and the function isn't called unless successful. 

$(document).ready(function() {

  var weatherAPI = 'http://api.openweathermap.org/data/2.5/weather';
  var data = {
    q : "Portland,OR",
    units : "metric"
  };
  function showWeather(weatherReport) {
    $('#temperature').text(weatherReport.main.temp);
  }
  $.getJSON(weatherAPI, data, showWeather);
});
Justin Estrada
Justin Estrada
34,995 Points
Justin Estrada
Justin Estrada
34,995 Points

Perfect so the answer is that the function is turned into a keyword and passing it as an argument doesn't need the '()', thanks.

Marcus Parsons
Marcus Parsons
15,719 Points

Absolutely correct. Anytime the "()" are used in conjunction with a named function (or self invoking function), that function is called then and there. There are special cases, however, where you just want to reference the function so that only when an event fires off, the function will execute. If we were to put the "()" beside the callback function in the "getJSON" function, the parser would immediately call the function before there was a success message sent back from the server along with the applicable data retrieved, and thus, you would receive an error.