<Button
android:id="@+id/button3"   //定義了一個Button取名為button3 
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:text="@string/the_button3" /> //引入string檔案中的the_button3(the_button3在string檔案中已經被定義過啦
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="@id/button3"    //讓button1處於button3 的above
android:layout_toLeftOf="@id/button3" <span style="font-family: Arial, Helvetica, sans-serif;">//讓button1處於button3 的toLeftOf</span>
android:text="@string/the_button1" />  <span style="font-family: Arial, Helvetica, sans-serif;">//引入string檔案中的the_button1(the_button1在string檔案中                                                                                                     //已經被定義過啦