How to use QML Extras ExifInfo & FileInfo classes?

Question

As part of a QML QtQuick app I'm working on, I want to retrieve certain photo file metadata: latitude, longitude, and file-create date. To this end, I've tried to use the ExifInfo class in ArcGISExtras 1.1. However, it doesn't seem to be working for me.

When I set ExifInfo.filePath, the resulting ExifInfo.isExifValid is always false, and the gpsLongitude and gpsLatitude properties are always NaN. Not even the undocumented refresh() method seems to do anything. I have verified that the filePath and url properties do change properly after this. I've tried this on Windows 10 and Android 9.

Do you have a sample that might show how to set the file and retrieve its EXIF properties? The doc page sample is lacking a little context.
ExifInfo QML Type | ArcGIS for Developers

Thanks.

[Edit]

A little trial and error showed me that it works to set ExifInfo.filePath with a value like "c:/photos/photo1.jpg" rather than using a url-style value such as "file:///c:/photos/photo1.jpg", and that setting the url property doesn't work.

LucasDanzinger · Accepted Answer

I gave this a try with a photo from my iPhone (attached) and it seems to work for me. Here is what I had (just copied from the API doc pretty much): // Copyright 2016 ESRI // // All rights reserved under the copyright laws of the United States // and applicable international laws, treaties, and conventions. // // You may freely redistribute and use this sample code, with or // without modification, provided you include the original copyright // notice and use restrictions. // // See the Sample code usage restrictions document for further information. // import QtQuick 2.6 import QtQuick.Controls 2.2 import Esri.ArcGISExtras 1.1 ApplicationWindow { id: appWindow width: 800 height: 600 title: "Untitled16" ExifInfo { id: exif1 filePath: "C:/temp/IMG_2776.jpg" function logExifMetadata() { console.log( " File: " + exif1.filePath + " Created: " + exif1.created + " Is Exif valid? " + exif1.isExifValid + " Exif version: " + exif1.extendedValue(0x9000) + " Camera manuf: " + exif1.imageValue(0x010F) + " Camera model: " + exif1.imageValue(0x0110) + " GPS latitude: " + exif1.gpsLatitude + " GPS longitude: " + exif1.gpsLongitude + " GPS altitude: " + exif1.gpsAltitude + " GPS speed: " + exif1.gpsValue(0x000D) + " All image tags: " + exif1.imageTags + " All extended tags: " + exif1.extendedTags + " All GPS tags: " + exif1.gpsTags); } } Button { onClicked: exif1.logExifMetadata() } } ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ And here is the output: File: C:/temp/IMG_2776.jpg Created: Wed Jan 23 14:42:26 2019 GMT-0600 Is Exif valid? true Exif version: Camera manuf: Apple Camera model: iPhone XR GPS latitude: 19.699025 GPS longitude: -155.46133333333333 GPS altitude: 34.08290480371253 GPS speed: 0 All image tags: 271,272,274,282,283,296,305,306,322,323 All extended tags: 33434,33437,34850,34855,36864,36867,36868,37121,37377,37378,37379,37380,37383,37385,37386,37396,37500,37521,37522,40960,40962,40963,41495,41729,41986,41987,41989,41990,42034,42035,42036 All GPS tags: 1,2,3,4,5,6,7,12,13,16,17,23,24,29,31‍‍‍‍‍‍‍‍‍‍‍‍‍ Perhaps there is something up with the images you are using, or maybe the formats being used aren't working correctly with the ExifInfo class. FYI, we missed in the doc that this class inherits FileInfo, so we will be fixing that up. All properties/methods on FileInfo are therefore also available on ExifInfo