In Android, How can I display an application selector based on file type?

Question

Apologies if this has already been answered - if someone can point me to an already-answered question, that would be great...

Very simply, I would like to be able to pop up a list of applications which can process a file of a given type - for instance, if I have a music file (mp3, ogg, whatever), I'd like to be able to display a list of all loaded media applications that can process the file and allow the user to select one.

I've been playing around with creating an intent to do this as follows:

Intent myIntent = new Intent();
myIntent.setAction(Intent.ACTION_VIEW);
myIntent.addCategory("android.intent.category.LAUNCHER");
myIntent.setType("mp3");
startActivity(myIntent);

but I've obviously gotten it wrong, since it crashes every time. Should I be using ACTION_PICK or ACTION_CHOOSER instead of ACTION_VIEW?

More importantly, is it possible to easily define all media players by something other than the Intent.type? I believe type should be a proper MIME type, in lower case, but I'm not sure what to use in this instance...

Please be gentle :)

Answer 1

To get the applications that can successfully open a given intent you'll use the PackageManager. Simply construct the intent as above and then use this code to get the applications that can handle the intent.

Intent myIntent = new Intent();
myIntent.setAction(Intent.ACTION_VIEW);
myIntent.addCategory("android.intent.category.LAUNCHER");
myIntent.setType("mp3");    

PackageManager manager = getPackageManager();
List<ResolveInfo> info = manager.queryIntentActivities(
    myIntent, PackageManager.MATCH_DEFAULT_ONLY);

This will give you all the information on the programs that can handle the intent, including icon, and packagename. You can then create a dialog box with these options and save the option the user chooses.

Answer 2

I assume you want to see this chooser dialog if you do open a file (or URL) and there is more than one application registered to handle it? E.g. you open a youtube URL and can chose to use the youtube player or browser?

That is the kind of intent the system sends when I want to open an image (through the file browser):

File f = new File("/sdcard/IMG_0114.JPG");
Uri uri = Uri.fromFile(f);

Intent i = new Intent(Intent.ACTION_VIEW);
// use setDataAndType() - setData() and setType() cancel each other
i.setDataAndType(uri, "image/jpeg");
i.putExtra("preview", false);
i.putExtra("key_filename", "/sdcard/IMG_0114.JPG");
i.putExtra(Intent.EXTRA_STREAM, uri);
i.putExtra("sort_order", 0);

// It's one of the flag combinations:
i.setFlags(Intent.FLAG_DEBUG_LOG_RESOLUTION);

i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK |
        Intent.FLAG_ACTIVITY_SINGLE_TOP |
        Intent.FLAG_ACTIVITY_MULTIPLE_TASK |
        Intent.FLAG_DEBUG_LOG_RESOLUTION);

startActivity(i);

EDIT: corrected code to get a working (minimal) solution.

I am not sure which fields of the extra data has to be set - didn't find documentation for that.