Access Expansion File Globally

Question

I need to access a lot of images from the expansion file throughout a lot of activities.

Doing the:

expansionFile = APKExpansionSupport.getAPKExpansionZipFile(context, 8, -1);
fileStream = expansionFile.getInputStream("drawables/drawable-hdpi/" + image);
Drawable drawable = Drawable.createFromStream(fileStream, null);

for every activity is very slow, in some activities I need to load 4 ou more images at the same time.

So what do you think if I create a new class that abstracts this code in every activity?

Answer 1

So I created a class ExpansionFileRetriever, that retrieves the expansion file:

public class ExpansionFileRetriever{

private static ExpansionFileRetriever instance;

public static ExpansionFileRetriever get() {
   if(instance == null) instance = getSync();
   return instance;
}

private static synchronized ExpansionFileRetriever getSync() {
   if(instance == null) instance = new ExpansionFileRetriever();
   return instance;
}

public ExpansionFileRetriever(){
   // here you can directly access the Application context calling
   Context c = App.get();
   try {
        expansionFile = APKExpansionSupport.getAPKExpansionZipFile(c, 20, -1);
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

ZipResourceFile expansionFile;

public Drawable getDrawable(String path, String resource) {
    InputStream fileStream = null;
    String file = path + resource;
    try {
        fileStream = expansionFile.getInputStream(file);
        Drawable drawable = Drawable.createFromStream(fileStream, null);
        return drawable;
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        return null;
    }   
}

}

and whenever I need to access files for the expansion file

I just use

ExpansionFileRetriever expFile = ExpansionFileRetriever.get();

and to get, say a Drawable all I do is:

expFile.getDrawable(path, name)