How to call resources with string name in android?

Question

I'm now trying to call the resources( in my application they are mp3 files and images). For the mp3 file part, my code goes like this ( not working obviously!)

if(i==1)
{
hoho= MediaPlayer.create(getApplicationContext(), R.raw.univ_day1);
hoho.start();
}
else if (i==2)
{
hoho= MediaPlayer.create(getApplicationContext(), R.raw.univ_day2);
hoho.start();  
}

...

In my application, there are hundreds of mp3 file inside the application. So what I want to do is briefly summarize code into something like this.

hoho=MediaPlayer.crate(getApplicationContet(), R.raw.univ_day+"i"); //This also looks really awkward.

If I knew how to write down code just like above one. How can I handle the name of raw files and the form like "R.raw...."? If I can do, then I also can apply similar approach to the image resources.

put your audio files in the assets directory and setup arrays of strings/filename then traverse it `AssetFileDescriptor descriptor = contex.getAssets() .openFd(fileName + i);` `mp.setDataSource(descriptor.getFileDescriptor(), descriptor.getStartOffset(), descriptor.getLength());` `descriptor.close()` — Spurdow, Aug 09 '14 at 14:43
possible duplicate of [Android: How do I get string from resources using its name?](http://stackoverflow.com/questions/7493287/android-how-do-i-get-string-from-resources-using-its-name) — nhaarman, Aug 09 '14 at 14:43
No its not. Here question is about getting the list of media files from the res folder not the list all the string resources names. — Devendra B. Singh, Aug 09 '14 at 15:06

score 6 · Answer 1 · answered Aug 09 '14 at 15:13

6

You can get resource id by its name using public int getIdentifier (String name, String defType, String defPackage) method. For example:

int id = getResources().getIdentifier("univ_day"+i, "raw", getPackageName());
hoho = MediaPlayer.create(getApplicationContext(), id);

answered Aug 09 '14 at 15:13

dahec

466
5
10

Make sure to check if `id != 0`. Since resource id 0 means that the resource was not found. – Hassaan Aug 09 '14 at 15:27
Thanks! This is what I've been looking for!! :) – Sungpah Lee Aug 13 '14 at 01:01

Devendra B. Singh · Accepted Answer · 2014-08-09T15:03:47.017

We can list all the names of raw assets, which are basically the filenames without the extensions, we can do this as -

public void listRaw(){
    Field[] fields=R.raw.class.getFields();
    for(int count=0; count < fields.length; count++){
        Log.i("Raw Asset: ", fields[count].getName());
    }
}

Next you'll need to refer to them by the integer assigned to that resource name. You can get this integer as:

int resourceID=fields[count].getInt(fields[count]);

This is the same int which you'd get by referring to R.raw.yourRawFileName.

In your code you can use this like -

hoho= MediaPlayer.create(getApplicationContext(), resourceID);
hoho.start();

Next you can apply JAVA logic to play previous current and next media files. Please let know if you need help here also.

How to call resources with string name in android?

2 Answers2