1 files changed, 13 insertions, 16 deletions

diff --git a/beamer/viewer/viewer.js b/beamer/viewer/viewer.js
index d8d7668..a10e6de 100644
--- a/beamer/viewer/viewer.js
+++ b/beamer/viewer/viewer.js
@@ -35,10 +35,9 @@ class Viewer {
   }
 
   _preparePresentation(source) {
-    const self = this;
-    pdfjsLib.getDocument(source).then(function(pdf) {
-      self.presentation = new Presentation(pdf);
-    }).catch(function(error) {
+    pdfjsLib.getDocument(source).then(pdf => {
+      this.presentation = new Presentation(pdf);
+    }).catch(error => {
       console.error(error);
       window.alert("Error while loading presentation:\n\n" + error.message);
       window.location.href = window.location.pathname; // reload without "?file=..."
@@ -46,9 +45,8 @@ class Viewer {
   }
 
   _readFile(file) {
-    const self = this;
-    this.fileReader.onload = function() {
-      self._setPresentation(new Uint8Array(this.result));
+    this.fileReader.onload = () => {
+      this._setPresentation(new Uint8Array(this.result));
     }
 
     this.fileReader.abort();
@@ -72,25 +70,24 @@ class Viewer {
   }
 
   _listenForInput() {
-    const self = this;
-    fileInput.addEventListener("change", function(event) {
-      self._readFile(event.target.files[0]);
+    fileInput.addEventListener("change", event => {
+      this._readFile(event.target.files[0]);
     });
 
-    startButton.addEventListener("click", function(event) {
+    startButton.addEventListener("click", event => {
       event.preventDefault();
       event.stopPropagation();
-      self.presentation.start();
+      this.presentation.start();
     });
 
-    document.body.addEventListener("drop", function(event) {
+    document.body.addEventListener("drop", event => {
       event.preventDefault();
       event.stopPropagation();
-      self.fileInput.files = event.dataTransfer.files;
-      self._readFile(event.dataTransfer.files[0]);
+      this.fileInput.files = event.dataTransfer.files;
+      this._readFile(event.dataTransfer.files[0]);
     });
 
-    document.body.addEventListener("dragover", function(event) {
+    document.body.addEventListener("dragover", event => {
       event.preventDefault();
       event.stopPropagation();
     });