Accessing resources programmatically

Question

Is it possible to receive the resource-ids being kept by a as an int[] programmatically without referring to the resource-class R?

Answer 1

Here is the solution that delivers the resource-IDs programmatically for the child-<attr>-tags defined for a <declare-styleable> tag:

/*********************************************************************************
*   Returns the resource-IDs for all attributes specified in the
*   given <declare-styleable>-resource tag as an int array.
*
*   @param  context     The current application context.
*   @param  name        The name of the <declare-styleable>-resource-tag to pick.
*   @return             All resource-IDs of the child-attributes for the given
*                       <declare-styleable>-resource or <code>null</code> if
*                       this tag could not be found or an error occured.
*********************************************************************************/
public static final int[] getResourceDeclareStyleableIntArray( Context context, String name )
{
    try
    {
        //use reflection to access the resource class
        Field[] fields2 = Class.forName( context.getPackageName() + ".R$styleable" ).getFields();

        //browse all fields
        for ( Field f : fields2 )
        {
            //pick matching field
            if ( f.getName().equals( name ) )
            {
                //return as int array
                int[] ret = (int[])f.get( null );
                return ret;
            }
        }
    }
    catch ( Throwable t )
    {
    }

    return null;
}

Maybe this could help somebody one day.

Answer 2

public static final int[] getResourceDeclareStyleableIntArray(String name) {
    int[] result = null;
    try {
        result = (int[]) R.styleable.class.getField(name).get(R.styleable.class);
    } catch (NoSuchFieldException e) {
        e.printStackTrace();
    } catch (IllegalAccessException e) {
        e.printStackTrace();
    }
    return result;
}

Answer 3

Slightly more efficient solution:

public static final int[] getResourceDeclareStyleableIntArray(String name) {
        Field[] allFields = R.styleable.class.getFields();
        for (Field field : allFields) {
            if (name.equals(field.getName())) {
                try {
                    return (int[]) field.get(R.styleable.class);
                } catch (IllegalAccessException ignore) {}
            }
        }

        return null;
    }