Problem
I am making a Chrome extension that downloads files and adds links to these downloaded files to a webpage. When these links are clicked, I would like to relay the click as a "user gesture" to my background script so that the file opens without prompting. Looking at the docs on the relevant method, chrome.downloads.open, there is no discussion of user gestures.
Essentially, I want to get rid of this =>
using the idea in this comment.
Background
It seems like this is possible because
- This post on what constitutes a user gesture lists click as one of the types of user gestures
- The spec, which says clicks will generate a user gesture
- In the code below, logging the
eventresults in a MouseEvent, with typeclickandisTrustedset to true. [downloads.open] can only run in a code initiated by a user action, like a click on a button. It cannot be executed from non-user events. - Xan, comment for How to open a downloaded file?
Code below aims to be an MCVE.
Content Script
// Add an event listener for every download link
function addDownloadListeners() {
const pathElems = document.getElementsByClassName('pathClass');
for (path of pathElems) {
path.addEventListener('click', openDownload);
}
}
// Send a message with the download ID to the background script
function openDownload(event) {
const selector = '#' + event.currentTarget.id;
const downloadId = parseInt($(selector).attr('download_id'));
chrome.runtime.sendMessage({
'downloadId': downloadId,
}, function(response) {
if (response !== undefined) {
resolve(response.response);
} else {
reject(new Error(response.response));
}
});
}
manifest.json
{
"background": {
"scripts": ["js/background.js"]
},
"content_scripts": [
{
"js": [
"js/content_script.js"
],
"matches": ["*://*.website.com/*/urlpath*"],
"run_at": "document_end"
}
],
"permissions": [
"downloads",
"downloads.open"
],
"manifest_version": 2,
}
Background Script
chrome.runtime.onMessage.addListener(
function(request, sender, sendResponse) {
try {
chrome.downloads.open(request.downloadId);
} catch (e) {
sendResponse({response: 'Error opening file with download id ' +
request.downloadId + ' getting error ' + e.toString()
});
}
}
)
Question
How can I get a click to open a download without creating an additional prompt?
