Android Tutorial - Android Raw Resources

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Android allows raw files in addition to arbitrary XML files. These resources, placed in /res/raw folder.

The raw files could be audio, video, or text files that require localization or references through resource IDs.

These files are not compiled but are moved to the application package as they are.

Each file has an identifier generated in R.java.

Example

If you were to place a text file at /res/raw/test.txt, you would be able to read that file using the following code.

String getStringFromRawFile(Activity activity)
throws IOException{
   Resources r = activity.getResources();
   InputStream is = r.openRawResource(R.raw.test);
   String myText = workOnInputStream(is);
   is.close();
   return myText;
}

File names with duplicate base names generate a build error.

Load and parse raw xml file

The following code shows how to Load and parse raw xml file.

Layout file

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="vertical"
  android:layout_width="fill_parent" 
  android:layout_height="fill_parent" >
  <TextView
    android:id="@+id/selection"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
  />
  <ListView
    android:id="@android:id/list"
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent"
    android:drawSelectorOnTop="false"
  />
</LinearLayout>

res/raw/words.xml

<words>
  <word value="lorem" />
  <word value="ipsum" />
  <word value="dolor" />
  <word value="sit" />
  <word value="amet" />
  <word value="consectetuer" />
  <word value="adipiscing" />
  <word value="elit" />
  <word value="morbi" />
  <word value="vel" />
  <word value="ligula" />
  <word value="vitae" />
  <word value="arcu" />
  <word value="aliquet" />
  <word value="mollis" />
  <word value="etiam" />
  <word value="vel" />
  <word value="erat" />
  <word value="placerat" />
  <word value="ante" />
  <word value="porttitor" />
  <word value="sodales" />
  <word value="pellentesque" />
  <word value="augue" />
  <word value="purus" />
</words>

Java code

import android.app.Activity;
import android.os.Bundle;
import android.app.ListActivity;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import java.io.InputStream;
import java.util.ArrayList;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
/*from   w ww . j  av a 2 s  .  c om*/
public class MainActivity extends ListActivity {
  TextView selection;
  ArrayList<String> items=new ArrayList<String>();
  
  @Override
  public void onCreate(Bundle icicle) {
    super.onCreate(icicle);
    setContentView(R.layout.main);
    selection=(TextView)findViewById(R.id.selection);
    
    try {
      InputStream in=getResources().openRawResource(R.raw.words);
      DocumentBuilder builder=DocumentBuilderFactory
                                .newInstance()
                                .newDocumentBuilder();
      Document doc=builder.parse(in, null);
      NodeList words=doc.getElementsByTagName("word");
      
      for (int i=0;i<words.getLength();i++) {
        items.add(((Element)words.item(i)).getAttribute("value"));
      }
      
      in.close();
    }
    catch (Throwable t) {
      Toast
        .makeText(this, "Exception: "+t.toString(), 2000)
        .show();
    }
    
    setListAdapter(new ArrayAdapter<String>(this,
                                  android.R.layout.simple_list_item_1,
                                  items));
  }
  
  public void onListItemClick(ListView parent, View v, int position,
                  long id) {
    selection.setText(items.get(position).toString());
  }
}
/***
  Copyright (c) 2008-2009 CommonsWare, LLC
  
  Licensed under the Apache License, Version 2.0 (the "License"); you may
  not use this file except in compliance with the License. You may obtain
  a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/

Static Resources

Here is the three steps to use static resource:

• Put files to your package's res/raw folder
• Use the getResources() method from the Activity class to return a Resources object
• Use its openRawResource() method to open the file contained in the res/raw folder

package com.java2s.myapplication3.app;
//from   w  ww . j a v a 2 s . co m
import android.app.Activity;
import android.os.Bundle;
import android.widget.EditText;
import android.widget.Toast;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

public class MainActivity extends Activity {
    EditText textBox;
    static final int READ_BLOCK_SIZE = 100;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        textBox = (EditText) findViewById(R.id.txtText1);

        InputStream is = this.getResources().openRawResource(R.raw.textfile);
        BufferedReader br = new BufferedReader(new InputStreamReader(is));
        String str = null;
        try {
            while ((str = br.readLine()) != null) {
                Toast.makeText(getBaseContext(),
                        str, Toast.LENGTH_SHORT).show();
            }
            is.close();
            br.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

The resource ID of the resource stored in the res/raw folder is named after its filename without its extension. For example, if the text file is textfile.txt, then its resource ID is R.raw.textfile.

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