center GUI-elements using the example of TextView

A GUI-element can be simply centered through the parameter „gravity“ in the definding XML-file:

<TextView  
   android:layout_width="fill_parent" 
   android:layout_height="fill_parent" 
   android:gravity="center_horizontal|center_vertical"
   android:text="Zentrierter Text"
/>

It is important to combine the centering with „fill_parent“.