Warning shows when i use Hash Map In android(Use new SparseArray)

Question

I am new to developing in android. In my android app I\'m using HashMap, but I\'m getting a warning:

**\"Use new SparseArray(...) ins         


        

Answer 1

Use new SparseArray(...) instead for better performance

You are getting this warning because of reason described here.

SparseArrays map integers to Objects. Unlike a normal array of Objects, there can be gaps in the indices. It is intended to be more efficient than using a HashMap to map Integers to Objects.

Now

how i use SparseArray ?

You can do it by below ways:

1. HashMap way:

   Map _bitmapCache = new HashMap();
   private void fillBitmapCache() {
        _bitmapCache.put(R.drawable.icon, BitmapFactory.decodeResource(getResources(), R.drawable.icon));
        _bitmapCache.put(R.drawable.abstrakt, BitmapFactory.decodeResource(getResources(), R.drawable.abstrakt));
        _bitmapCache.put(R.drawable.wallpaper, BitmapFactory.decodeResource(getResources(), R.drawable.wallpaper));
        _bitmapCache.put(R.drawable.scissors, BitmapFactory.decodeResource(getResources(), 
    }
   
   Bitmap bm = _bitmapCache.get(R.drawable.icon);
   

2. SparseArray way:

   SparseArray _bitmapCache = new SparseArray();
   private void fillBitmapCache() {
        _bitmapCache.put(R.drawable.icon, BitmapFactory.decodeResource(getResources(), R.drawable.icon));
        _bitmapCache.put(R.drawable.abstrakt, BitmapFactory.decodeResource(getResources(), R.drawable.abstrakt));
        _bitmapCache.put(R.drawable.wallpaper, BitmapFactory.decodeResource(getResources(), R.drawable.wallpaper));
        _bitmapCache.put(R.drawable.scissors, BitmapFactory.decodeResource(getResources(), 
    }
   
   Bitmap bm = _bitmapCache.get(R.drawable.icon);
   

Hope it Will Help.