Access string.xml Resource File from Java Android Code

Well you can get String using,

getString(R.string.app_name);

And, you can get string-array using

String arr[] = getResources().getStringArray(R.array.planet);
for (int i = 0; i < arr.length; i++) {
        Toast.makeText(getBaseContext(),arr[i], Toast.LENGTH_LONG).show();  
}

If getString(R.string.app_name); isn't working for you, you can pass context like this:

context.getString(R.string.app_name);

Put this code in res/values/string.xml

<string-array name="planet"> 
    <item>Mercury</item>
    <item>Venus</item>
    <item>Earth</item>
    <item>Mars</item>
</string-array>

This code to be placed in res/layout/main.xml and remove default widgets present in main.xml.

<ListView android:id="@+id/planet"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:entries="@array/planet"/>
</LinearLayout>

strings.xml:

<string name="some_text">Some Text</string>

Activity:

getString(R.string.some_text);