Flutter plugin that downloads images on the Internet and saves them on device.
This will keep Exif(DateTimeOriginal) and GPS(Latitude, Longitude).

For Android, image is saved in Environment.DIRECTORY_DOWNLOADS.
For ios, image is saved in Photo Library.

Add the following keys to your Info.plist file, located in /ios/Runner/Info.plist:

• NSPhotoLibraryUsageDescription - Specifies the reason for your app to access the user’s photo library. This is called Privacy - Photo Library Usage Description in the visual editor.
• NSPhotoLibraryAddUsageDescription - Specifies the reason for your app to get write-only access to the user’s photo library. This is called Privacy - Photo Library Additions Usage Description in the visual editor.

Add this permission in AndroidManifest.xml. (If you call AndroidDestinationType#inExternalFilesDir(), This setting is not necessary.)

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

try {
  // Saved with this method.
  var imageId = await ImageDownloader.downloadImage("https://raw.githubusercontent.com/wiki/ko2ic/image_downloader/images/flutter.png");
  if (imageId == null) {
    return;
  }

  // Below is a method of obtaining saved image information.
  var fileName = await ImageDownloader.findName(imageId);
  var path = await ImageDownloader.findPath(imageId);
  var size = await ImageDownloader.findByteSize(imageId);
  var mimeType = await ImageDownloader.findMimeType(imageId);
} on PlatformException catch (error) {
  print(error)
}

The return value is as follows.

• imageId of the saved image if saving succeeded.
• null if not been granted permission.
• Otherwise it is a PlatformException.

You can specify the storage location.
(Currently, external storage is only supported on Android.)

Three directories by default are provided.

• AndroidDestinationType.directoryDownloads -> Environment.DIRECTORY_DOWNLOADS on Android
• AndroidDestinationType.directoryPictures -> Environment.DIRECTORY_PICTURES on Android
• AndroidDestinationType.directoryDCIM -> Environment.DIRECTORY_DCIM on Android

In addition, there is also custom.

For example, the following sources is stored in /storage/emulated/0/sample/custom/sample.gif.
(Depends on the device.)

await ImageDownloader.downloadImage(url,
                                    destination: AndroidDestinationType.custom('sample')                                  
                                    ..subDirectory("custom/sample.gif"),
        );

For example, the following sources is stored in /storage/emulated/0/Android/data/<applicationId>/files/sample/custom/sample.gifby calling inExternalFilesDir() .
(Depends on the device.)

 await ImageDownloader.downloadImage(url,
                                     destination: AndroidDestinationType.custom('sample')
                                     ..inExternalFilesDir()
                                     ..subDirectory("custom/sample.gif"),
         );

Note: inExternalFilesDir() will not require WRITE_EXTERNAL_STORAGE permission, but downloaded images will also be deleted when uninstalling.

https://github.com/ko2ic/image_downloader/wiki#trouble-shooting