When to use Sparse...

Here is a concise answer to the Android interview question "When to use SparseArray vs HashMap?":

SparseArray

Use SparseArray when:

• You need to store primitive integer keys and object values
• You want to optimize memory usage compared to HashMap
• You are working with a fixed set of keys that are integers

SparseArray is more memory efficient than HashMap for storing integer keys because it avoids the overhead of Integer wrapper objects. It's a good choice when you have a limited set of integer keys.

HashMap

Use HashMap when:

• You need to store arbitrary key-value pairs
• You want the f...