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downloads.getFileIcon()

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The getFileIcon() function of the downloads API retrieves an icon for the specified download.

For new downloads, file icons are available after the downloads.onCreated event has been received. The image returned by this function while a download is in progress may be different from the image returned after the download is complete.

Icon retrieval is done by querying the underlying platform. The icon that is returned will therefore depend on a number of factors including state of the download, platform, registered file types and visual theme.

If a file icon cannot be determined, runtime.lastError will be set with an appropriate error message.

Syntax

chrome.downloads.getFileIcon(
  downloadId,             // integer
  options,                // optional object
  function(iconURL) {...} // function
)

This API is also available as browser.downloads.getFileIcon() in a version that returns a promise.

Parameters

downloadId
An integer representing the ID of the download.
optionsOptional
An options object representing preferences for the icon to be retrieved. It can take the following properties:
sizeOptional
An integer representing the size of the icon. The returned icon's size will be the provided size squared (in pixels). If omitted, the default size for the icon is 32x32 pixels.
function
A callback function invoked when the icon has been fetched. The function is passed the following arguments:
iconURLOptional
A string representing the absolute URL of the icon.

Browser compatibility

Chrome Edge Firefox Firefox for Android Opera
Basic support Yes No No No 33

Examples

The following snippet fetches the DownloadItem  for the most recent download. If there is one, it attempts to retrieve the item's icon using getFileIcon().

The callback function updateIconUrl() displays the icon in an <img> element if the call was successful or handles the error case.

function updateIconUrl(iconUrl) {
  if (chrome.runtime.lastError) {
    console.error(chrome.runtime.lastError);
    iconUrl = "";
  }
  var downloadIcon = document.querySelector("#icon");
  downloadIcon.setAttribute("src", iconUrl);
}

function getIconForDownload(downloadItems) {
  if (downloadItems.length > 0) {
    latestDownloadId = downloadItems[0].id;
    chrome.downloads.getFileIcon(latestDownloadId, updateIconUrl);
  }
}

chrome.downloads.search({
  limit: 1,
  orderBy: ["-startTime"]
}, getIconForDownload);

Example add-ons

Acknowledgements

This API is based on Chromium's chrome.downloads API.

Microsoft Edge compatibility data is supplied by Microsoft Corporation and is included here under the Creative Commons Attribution 3.0 United States License.

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