Add dropdown to select which LED to toggle

www/page2.html

@@ -30,19 +30,37 @@
 <H2>This is the second page</H2>
 <p>This page is just to demonstrate linking to other local pages, and to test JavaScript stuff.
 <p align='center'>
-    <button type='button' class='btn' align='center' style='height:30px; width:70px' onclick='toggleLED()'>Toggle</button>
+    <select id="ledNumber">
+      <option value=1>1</option>
+      <option value=2>2</option>
+      <option value=3>3</option>
+      <option value=4>4</option>
+    </select>
+    <button id="ledToggleBtn" type='button' class='btn' align='center' style='height:30px; width:70px' onclick="toggleLED(parseInt(document.getElementById('ledNumber').value, 10))">Toggle</button>
 </p>
+<p id='statusMsg' align='center'>______</p>
+<p align='center'>
+    <button id="getSwitchBtn" type='button' class='btn' align='center' style='height:30px; width:110px' onclick="getSwitch()">Get Switch</button>
+</p>
+<p id='switchMsg' align='center'>______</p>
 <BR><BR><BR>
 Send questions to <a href="mailto:supporrt@emacinc.com">support@emacinc.com</a>.
 <HR>
 <a href="index.html">Home</a>
 <script>
-  function toggleLED() {
+  function toggleLED(led_num) {
     var xhr = new XMLHttpRequest();
     xhr.open("POST", "/led_control", true);
     xhr.setRequestHeader('Content-Type', 'application/json');
+    xhr.onreadystatechange = function() {
+      if (this.readyState == XMLHttpRequest.DONE && this.status == 200) {
+        var data = xhr.responseText;
+        var jsonResponse = JSON.parse(data);
+        document.getElementById("statusMsg").innerHTML = jsonResponse['status'];
+      }
+    }
     xhr.send(JSON.stringify({
-      number: 1,
+      number: led_num,
       action: 'toggle'
     }));
   };