Question

I noticed myself constantly typing:

someVar = getResources().getString(R.string.someString);

I have several XML files that I am parsing and building and in order to make sure that the files stay consistent, I have placed the tag names in the res/values/strings.xml file. The same handles are used throughout several activities, and some of those activities extend ListActivity while others do not so creating a simple super class which houses these variables ( ex:

public class thisClass extends thatClass 
{...}

public class thatClass 
{
    package String someTag = "this";
    package String otherTag = "that"; 
}

I would assume that all of these calls to getResources() could get pretty taxing and was wondering if it is beneficial to instead create an R-type file where I can store these types of commonly used variables statically ex:

public final class globalVars 
{
    public static final class XML_TAGS 
    {
        static final String someTag = "this";
        static final String otherTag = "that";
    }
}

and to reference these variables like such:

serializer.startTag("", globalVars.XML_TAGS.someTag);

instead of

serializer.startTag("", getResources().getString(R.string.someTag));

Thanks for the input!

Answer 1

OK, after looking into the source code of android.content.res.resources and some other classes, it is evident that using Resources and getting resources through getResources() is costly compared to a static class.

Indeed, the instance of Resources returned is not a static container but rather an object that gets resources by executing a couple of statements (whether a string or drawable or any other form).

However, using getResources() has its advantages:

• It helps you externalize your resources.
• For any type of resource, you can specify default and multiple alternative resources depending maybe on Locale, Screen Depth/Resolution…

A static container might provide a less costly alternative than using resources but remember: any later attempt at localization would be relatively extremely costly.