How do I get a Uri to an image in my Assets that will work for the SearchManager.SUGGEST_COLUMN_ICON_1 column?

Question

I have successfully integrated my app\'s country search into the global search facility and now I am trying to display each country\'s flag next to the search suggestions.

Answer 1

Sadly after much searching around I have reached the conclusion that you cannot return a uri to an image asset to the search facility. What I did instead was move my flag images to the resources (so they do not clutter up my app's resources I created a library for the flag images) and use resource uri's. So, in my provider I have code that looks like this in the loop that maps database results to search results:

            if (requestedColumns[index].compareTo (SearchManager.SUGGEST_COLUMN_ICON_1) == 0)  {
                //  Translate the country code into a flag icon uri
                String countryCode = dbResults.getString (
                        dbResults.getColumnIndexOrThrow (queryMappedColumns[index]));

                int flagImageID = FlagLookup.smallFlagResourceID (countryCode);
                String flagUriStr = "android.resource://com.lesliesoftware.worldinfo/" + flagImageID;
                columnValues.add (flagUriStr);
            }  

and look up code that looks like this:

static public int smallFlagResourceID (String countryCode)  {
    if (countryCode == null || countryCode.length () == 0)
        return R.drawable.flag_small_none;

    if (countryCode.equalsIgnoreCase ("aa"))
        return R.drawable.flag_small_aa;
    else if (countryCode.equalsIgnoreCase ("ac"))
        return R.drawable.flag_small_ac;
    else if (countryCode.equalsIgnoreCase ("ae"))
        return R.drawable.flag_small_ae;
    ...

I will just have to make sure I create a test that verifies that all countries that have flags returns the expected results.

Answer 2

Just wanted to add to vidstige's answer: I wanted to serve files that I had downloaded to my temporary cache directory earlier, so I can serve external image thumbnails to the SearchView suggestions from URLs in my search ContentProvider. I used this function instead:

@Override
public AssetFileDescriptor openAssetFile(Uri uri, String mode) throws FileNotFoundException {
        String filename = uri.getLastPathSegment();

        try {
            File file = new File(getContext().getCacheDir(), filename);

            // image downloading has to be done in the search results provider, since it's not on the UI thread like this guy.
            //downloadAndSaveFile("http://urdomain/urfile.png", filename);

            AssetFileDescriptor afd = new AssetFileDescriptor(
                        ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY | ParcelFileDescriptor.MODE_WORLD_READABLE),
                    0, AssetFileDescriptor.UNKNOWN_LENGTH);

            return afd;
        } catch (IOException e) {
            throw new FileNotFoundException("No asset found: " + uri);
        }
    }

Answer 3

You first create an AssetProvider. We will later create uris that will be handled by this class.

public class AssetsProvider extends ContentProvider {

    private AssetManager assetManager;
    public static final Uri CONTENT_URI = 
            Uri.parse("content://com.example.assets");

    @Override
    public int delete(Uri arg0, String arg1, String[] arg2) { return 0; }

    @Override
    public String getType(Uri uri) { return null; }

    @Override
    public Uri insert(Uri uri, ContentValues values) { return null; }

    @Override
    public boolean onCreate() {
        assetManager = getContext().getAssets();
        return true;
    }

    @Override
    public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { return null; }

    @Override
    public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) { return 0; }

    @Override
    public AssetFileDescriptor openAssetFile(Uri uri, String mode) throws FileNotFoundException {
        String path = uri.getPath().substring(1);
        try {
            AssetFileDescriptor afd = assetManager.openFd(path);
            return afd;
        } catch (IOException e) {
            throw new FileNotFoundException("No asset found: " + uri, e);
        }
    }
}

Lot's of boilerplate in there. The essential method is of course the openAssetFile that justs translates the path of the uri passed to it into a AssetFileDescriptor. In order for Android to be able to pass URIs to this provider, remember to include this in your AndroidManifest.xml file inside the application-tag:

    <provider
        android:name=".AssetsProvider"
        android:authorities="com.example.assets" />

Now, in your search provider you can create an URI like this:

content://com.example.assets/my_folder_inside_assets/myfile.png

Answer 4

I was able to refer images from drawable in SearchRecentSuggestionsProvider using following uri,

"android.resource://your.package.here/drawable/image_name