<resources>
<style name="Theme.SoundRecorder" parent="@android:style/Theme.Holo.DialogWhenLarge">
<item name="android:windowCloseOnTouchOutside">false</item>
</style>
</resources>

YourActivity.this.setFinishOnTouchOutside(false);

@Override
public boolean onTouchEvent(MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_DOWN && isOutOfBounds(this, event)) {
return true;
}
return super.onTouchEvent(event);
}

private boolean isOutOfBounds(Activity context, MotionEvent event) {
final int x = (int) event.getX();
final int y = (int) event.getY();
final int slop = ViewConfiguration.get(context).getScaledWindowTouchSlop();
final View decorView = context.getWindow().getDecorView();
return (x < -slop) || (y < -slop)|| (x > (decorView.getWidth() + slop))|| (y > (decorView.getHeight() + slop));
}