From 6c3856c841b90efa77a0554851456613d8a7ddd5 Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Sat, 16 Sep 2017 13:05:01 +0200
Subject: [PATCH] Ignore 'change' events that didn't originate in the viewer
 (issue 8915)

Rather that registering a 'change' event listener on the `window`, which will thus (unnecessarily) fire in *a number* of other situations such as e.g. when the user changes the pageNumber or the current search term, we could/should just register it directly on the dynamically created `fileInput` DOM element instead.
I can see no really compelling reason why we actually need to listen for `file` changes on the `window` itself, and this way we're also able to keep the `fileInput` related code confined to one part of the code which should aid readability.
Furthermore, in custom deployments, there's less risk that we're going to interfere with "outside" code this way.

Finally, preprocessor guards were added to the `webViewerOpenFile` function, since that code doesn't make sense in e.g. the extension builds.
---
 web/app.js | 32 ++++++++++++++------------------
 1 file changed, 14 insertions(+), 18 deletions(-)

diff --git a/web/app.js b/web/app.js
index 3c5ebca60..dc3c6044b 100644
--- a/web/app.js
+++ b/web/app.js
@@ -1330,18 +1330,6 @@ let PDFViewerApplication = {
     window.addEventListener('hashchange', _boundEvents.windowHashChange);
     window.addEventListener('beforeprint', _boundEvents.windowBeforePrint);
     window.addEventListener('afterprint', _boundEvents.windowAfterPrint);
-    if (typeof PDFJSDev === 'undefined' || PDFJSDev.test('GENERIC')) {
-      _boundEvents.windowChange = (evt) => {
-        let files = evt.target.files;
-        if (!files || files.length === 0) {
-          return;
-        }
-        eventBus.dispatch('fileinputchange', {
-          fileInput: evt.target,
-        });
-      };
-      window.addEventListener('change', _boundEvents.windowChange);
-    }
   },
 
   unbindEvents() {
@@ -1396,10 +1384,6 @@ let PDFViewerApplication = {
     window.removeEventListener('hashchange', _boundEvents.windowHashChange);
     window.removeEventListener('beforeprint', _boundEvents.windowBeforePrint);
     window.removeEventListener('afterprint', _boundEvents.windowAfterPrint);
-    if (typeof PDFJSDev === 'undefined' || PDFJSDev.test('GENERIC')) {
-      window.removeEventListener('change', _boundEvents.windowChange);
-      _boundEvents.windowChange = null;
-    }
 
     _boundEvents.windowResize = null;
     _boundEvents.windowHashChange = null;
@@ -1492,6 +1476,16 @@ function webViewerInitialized() {
     } else {
       fileInput.value = null;
     }
+
+    fileInput.addEventListener('change', function(evt) {
+      let files = evt.target.files;
+      if (!files || files.length === 0) {
+        return;
+      }
+      PDFViewerApplication.eventBus.dispatch('fileinputchange', {
+        fileInput: evt.target,
+      });
+    });
   } else {
     appConfig.toolbar.openFile.setAttribute('hidden', 'true');
     appConfig.secondaryToolbar.openFileButton.setAttribute('hidden', 'true');
@@ -1859,8 +1853,10 @@ function webViewerPresentationMode() {
   PDFViewerApplication.requestPresentationMode();
 }
 function webViewerOpenFile() {
-  let openFileInputName = PDFViewerApplication.appConfig.openFileInputName;
-  document.getElementById(openFileInputName).click();
+  if (typeof PDFJSDev === 'undefined' || PDFJSDev.test('GENERIC')) {
+    let openFileInputName = PDFViewerApplication.appConfig.openFileInputName;
+    document.getElementById(openFileInputName).click();
+  }
 }
 function webViewerPrint() {
   window.print();