Eclipse XML editor shows android1 not android and no auto-complete

I'm using eclipse for Android programming, Today when i open to resume my app development the xml editor did't know the android tag at all like android:layout_...., It's knows android1 and the auto complete not working and says "Element is unknown"!

Here's an example :

<TextView
    android1:id="@+id/textView1"
    android1:layout_width="wrap_content"
    android1:layout_height="wrap_content"
    android1:layout_alignRight="@+id/help"
    android1:textSize="20dp" />

Any ideas to solve it ?