Add swipe support

touch-support.js

@@ -0,0 +1,27 @@
+// Reference: https://www.delftstack.com/howto/javascript/detect-finger-swipe-events-in-javascript/
+
+window.addEventListener('load', () => {
+  document.body.addEventListener('touchstart', onTouchStart);
+  document.body.addEventListener('touchmove', onTouchMove);
+  document.body.addEventListener('touchend', onTouchEnd);
+})
+
+var startX, startY, moveX, moveY;
+
+function onTouchStart(e){
+  startX = e.touches[0].clientX;
+  startY = e.touches[0].clientY;
+}
+
+function onTouchMove(e){
+  moveX = e.touches[0].clientX;
+  moveY = e.touches[0].clientY;
+}
+
+function onTouchEnd(){
+  if (startY+100 < moveY){
+    goToPreviousSlide();
+  } else if (startY-100 > moveY){
+    goToNextSlide();
+  }
+}