How do I call a function that is defined inside of require() outside of the require()?

I am using ArcGIS API for Javascript 3.21. I have a function inside of the require(). I want the function to be called when a button is clicked, but the button is outside the require().

<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" href="//js.arcgis.com/3.7/js/esri/css/esri.css">
<style>
    html, body, #map {
    height: 100%;
    width: 100%;
    margin: 1;
    padding: 1; 
    }
</style>

<script src="//js.arcgis.com/3.7/"></script>
<script>

    var map;

    require([
      "esri/map", 
      "esri/geometry/Point",
      "esri/symbols/SimpleMarkerSymbol",
      "esri/graphic", 
      "esri/layers/GraphicsLayer",
      "dojo/domReady!"
    ], function(
      Map, Point, SimpleMarkerSymbol, Graphic, GraphicsLayer
    ) {
      map = new Map("map", {
      basemap: "gray",
      center: [10,10],
      zoom: 3
    });

    map.on("load", function() {
      var graphicslayer = new GraphicsLayer();
      map.addLayer(graphicslayer);
    });

   function hello(){
      alert("hello,world!");
   }   

});



</script>
</head>
<body>

    <button type="submit"class="searchButton"onclick="hello()">Search</button>
    <div id="map"></div>

</body>
</html>

I can't call hello() in onclick="hello()" because hello() is inside the require().

Solution

Your hello function is scoped to the require function. You want to scope it to the global object, which is the window object in your case. So either:

function hello(){
    alert("hello,world!");
}   
window.hello = hello;

or directly

window.hello = function(){
    alert("hello,world!");
}

But you could also bind your hello function to the click event of your object directly in javascript; you don't have to widen the scope of your function. There is likely methods to do so in the dojo library. A direct javascript way could be something like

var myButton = document.querySelectorAll("button.searchButton")[0];
if (myButton) {
    myButton.addEventListener("click", hello);
}