Android :: Launch Email Intent With Attached Image

I am trying to launch an email intent with an attached jpg. I did:

Intent intent4 = new Intent(Intent.ACTION_SENDTO,
Uri.fromParts("mailto", "testemail@gmail.com", null));
startActivity(intent4);
this launches the email activity.
But when I try to add DataAndType (my jpeg attachment). It fails with
android.content.ActivityNotFoundException: No Activity found to handle Intent { action=android.intent.action.SENDTO data=file:///data/data/com.mycompany.mypackage/files/temp-picture type=JPEG
Intent intent4 = new Intent(Intent.ACTION_SENDTO,
Uri.fromParts("mailto", "testemail@gmail.com", null));
intent4.setDataAndType(Uri.parse("file://"+ mTempFilePath),
Bitmap.CompressFormat.JPEG.name());
startActivity(intent4);