ACTION_SEND, the Chooser, and ClipData

Roderick Gadellaa pointed out an interesting problem with the ���share sheet���.In Android 10+, the share sheet can show a preview of your content. In particular,it can show a preview of an image that you are sharing. The catch is that theshare sheet needs to know what image that is��� and whether it does depends on howyou are sharing it.

Sharing content involves ACTION_SEND, and if we use EXTRA_STREAM to supplya Uri, we need to add FLAG_GRANT_READ_URI_PERMISSION and/or FLAG_GRANT_WRITE_URI_PERMISSIONon the Intent:

val intent = Intent(Intent.ACTION_SEND).apply { putExtra(Intent.EXTRA_STREAM, uri) type = "image/webp" addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)}

Frequently, when using ACTION_SEND, we wrap it in a chooser Intent, suchas via Intent.createChooser(). So, we pass our Intent to createChooser() androll from there:

val intent = Intent(Intent.ACTION_SEND).apply { putExtra(Intent.EXTRA_STREAM, uri) type = "image/webp" addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)}startActivity(Intent.createChooser(intent, null))

And, if you try this, you will not get a preview in the share sheet.

This, however, works:

val intent = Intent(Intent.ACTION_SEND).apply { clipData = ClipData.newRawUri(null, uri) putExtra(Intent.EXTRA_STREAM, uri) type = "image/webp" addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)}startActivity(Intent.createChooser(intent, null))

The reason is that the framework copies the ClipData out of the ACTION_SENDand puts it in the ACTION_CHOOSER Intent created by createChooser().It does not copy any EXTRA_STREAM value, though.

There is also the possibility that you are using ShareCompat.IntentBuilder:

ShareCompat.IntentBuilder.from(this) .setType("image/webp") .addStream(uri) .startChooser()

This too fails��� for now. cketti filed an issue for that one,and while it is fixed, I do not believe that fix has shipped yet.

Ideally, you use setClipData() on an ACTION_SEND Intent or that repaired versionof ShareCompat.IntentBuilder, so your shared images are able to be previewedproperly.