Why does not an app resize to fit the screen with large screen, 160dpi?

It is a simple test app which displays the sentence based on the screen si开发者_运维知识库ze and density. If I start an emulator with WVGA800 skin with 160dpi resolution the app does not fill the whole screen but just a smaller square. Look at the image please.

As most of LARGE and XLARGE devices use this 160dpi resolution, what should I do to make app fill the screen as it fills it in other screen sizes and resolutions? Or this is just an issue with the emulator and the real device resize the app to fit its screen?!

Do you have something like this in your manifest:

<uses-sdk android:minSdkVersion="4" />