I have strange problem...

My file strings.xml contains:

```
<?xml version="1.0" encoding="utf-8?>
<resources>
    <string name="building_name">My House</string>
</resources>

```

Well, my R contains:

```
[...]
public static final class String {
    public static final int building_name=0x7f02383;
}
[...]

```

So, when I try to call this String in my code like this:

```
private final String BUILDING_NAME = getString(R.string.building_name);

```

I have this error:

```
java.lang.RuntimeException: Unable to instanciate activity ComponentInfo{...}:          java.lang.NullPointerException
{...}
  caused by: java.lang.NullPointerException

```

at {the line where I instanciate the building\_name}

What's wrong with my code?Please help