getResourceId method of TypedArray

Question

I am reading docs about getResourceId() method. It says that:

Retrieves the resource identifier for the attribute at index. Note that attribute resource as resolved when the overall TypedArray object is retrieved. As a result, this function will return the resource identifier of the final resource value that was found, not necessarily the original resource that was specified by the attribute.

So

• the first paragraph is clear:

Retrieves the resource identifier for the attribute at index.

• the second is clear too:

Note that attribute resource as resolved when the overall TypedArray object is retrieved.

• but what means the 3 paragraph? why it could return not necessarily the original resource id?

As a result, this function will return the resource identifier of the final resource value that was found, not necessarily the original resource that was specified by the attribute.

Answer 1

From the documentation:

TypedArray obtainStyledAttributes (AttributeSet set, 
                int[] attrs, 
                int defStyleAttr, 
                int defStyleRes)

....

When determining the final value of a particular attribute, there are four inputs that come into play:

1. Any attribute values in the given AttributeSet.
2. The style resource specified in the AttributeSet (named "style").
3. The default style specified by defStyleAttr and defStyleRes
4. The base values in this theme.