Fix pause_soundfile example in Safari by calling getAudioContext().resume() on user interaction before any other audio code

Author: oshoham

examples/pause_soundfile/sketch.js

@@ -1,8 +1,10 @@
 // ====================
 // DEMO: pause sound when the user presses a key, resume on release
 // ====================
+'use strict';
 
 var soundFile;
+var audioContextStarted = false;
 
 function preload() {
   // create a SoundFile
@@ -14,16 +16,26 @@ function setup() {
   createCanvas(400, 400);
   background(0, 255, 0);
 
-  soundFile.loop();
+  userStartAudio().then(function() {
+    soundFile.loop();
+    audioContextStarted = true;
+  });
+
   createP('Press any key to pause. Resume when the key is released')
 }
 
 function keyTyped() {
-    soundFile.pause();
-    background(255, 0, 0);
+  if (!audioContextStarted) {
+    return;
+  }
+  soundFile.pause();
+  background(255, 0, 0);
 }
 
 function keyReleased() {
-    soundFile.play();
-    background(0, 255, 0);
+  if (!audioContextStarted) {
+    return;
+  }
+  soundFile.play();
+  background(0, 255, 0);
 }