This is the solution I came up with:
This function allows you to share to instagram, facebook or any other app if you know the package name. If the app is not installed it redirects to the Play Store. If you send "others" as parameters, you will display a list of apps that also support image sharing.
shareImageIntent(mActivity,"image/*", "/storage/emulated/0/Pictures/Instagram/IMG_20150120_095603.jpg", "Instagram Sharing test. #Josh","com.instagram.android"); // parameters - for facebook: "com.facebook.katana" , to display list of other apps you can share to: "others"
public void shareImageIntent(Activity a,String type, String mediaPath, String caption, String app){
Intent intent = mContext.getPackageManager().getLaunchIntentForPackage(app);
if ((intent != null)||(app.equals("others"))){
// Create the new Intent using the 'Send' action.
Intent share = new Intent(Intent.ACTION_SEND);
if(!app.equals("others"))
share.setPackage(app);
// Set the MIME type
share.setType(type);
// Create the URI from the media
File media = new File(mediaPath);
Uri uri = Uri.fromFile(media);
// Add the URI and the caption to the Intent.
share.putExtra(Intent.EXTRA_STREAM, uri);
share.putExtra(Intent.EXTRA_TEXT, caption);
// Broadcast the Intent.
//startActivity(Intent.createChooser(share, "Share to"));
a.startActivity(share);
}
else{
intent = new Intent(Intent.ACTION_VIEW);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
//intent.setData(Uri.parse("market://details?id="+"com.instagram.android"));
intent.setData(Uri.parse("market://details?id="+app));
a.startActivity(intent);
}
}