android - 访问以编程方式获取资源

Question

是否可以在不引用资源类 R 的情况下以编程方式接收由 a 作为 int[] 保存的资源 ID？

<declare-styleable name="com_facebook_login_view">
    <attr name="confirm_logout" format="boolean"/>
    <attr name="fetch_user_info" format="boolean"/>
    <attr name="login_text" format="string"/>
    <attr name="logout_text" format="string"/>
</declare-styleable>

问题是我无法解析已定义的“declare-styleable”属性的 ID - 总是返回 0x00：

int id = context.getResources().getIdentifier( "com_facebook_login_view", "declare-styleable", context.getPackageName() ); 
int[] resourceIDs = context.getResources().getIntArray( id );

Answer 1

child-<attr>-tags这是以编程方式为定义的<declare-styleable>标签提供资源 ID 的解决方案：

/*********************************************************************************
*   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;
}

也许有一天这可以帮助某人。

Answer 2

稍微更有效的解决方案：

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;
    }

Answer 3

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;
}