HELP:problem in android xml code at eclipse 3.7

in one of my android app,all xml file not give me attribute prompt ,for example android: ,if i write as android: ,the eclipse not give me prompt ,i donot know why,my xml in other pc eclipse is all right,and xml file of my eclipse other android app can give me attribute prompt,i restart pc and eclipse but no use,why? my eclipse is 3.7 edit: i reinstall eclipse not help

 <?xml version="1.0" encoding="utf-8"?>

<RelativeLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
    android:background="@null" 
    android:id="@+id/add">
  <LinearLayout  android:layout_alignParentTop="true" 
              android:layout_width="fill_parent"
              android:layout_height="fill_parent"
              android:gravity="center" 
              android:id="@+id/liangdu"
              android:layout_marginTop="5dip"
              android:layout_marginBottom="90dip" >   
    <ImageView  android:layout_width="wrap_content"
            android:id="@+id/sv"
            android:layout_height="wrap_content"
           />

    <LinearLayout   android:layout_alignParentBottom="true"
                    android:layout_above="@id/liangdu"
                    android:id="@+id/bottom" 
                    android:orientation="vertical"
                    android:layout_width="fill_parent"
                    android:layout_height="100dip"
                    android:visibility="invisible"
                    android:background="@drawable/edit_xuanzhuan" >
       <RelativeLayout  android:layout_width="fill_parent"
                        android:layout开发者_如何学运维_height="50dip"
                        >

            <TextView android:layout_width="wrap_content"
                      android:layout_height="20dip"
                      android:layout_marginLeft="20dip"
                      android:layout_marginTop="20dip"
                      android:id="@+id/tv"
                      android:gravity="right"
                      android:text="亮    度"
                      android:textColor="#ffffff"/>
            <SeekBar

                      android:layout_marginTop="20dip"
                      android:layout_toRightOf="@id/tv"
                      android:id="@+id/liangduSeekBar"
                      android:layout_width="210dip" 

                      android:layout_height="wrap_content" 
                      android:minHeight="6dip"
                      android:maxHeight="6dip"
                      android:paddingLeft="15px"
                      android:paddingRight="5px"
                      android:max="100"
                      android:progress="50"
                      android:thumbOffset="3px"
                      android:progressDrawable="@drawable/seekbar_progress"
                      android:thumb="@drawable/seekbarthumb"/>

       </RelativeLayout>
       <RelativeLayout  android:layout_width="fill_parent"
                        android:layout_height="50dip"
                        >

            <TextView android:layout_width="wrap_content"
                      android:layout_height="20dip"
                      android:layout_marginLeft="20dip"
                      android:layout_marginTop="10dip"
                      android:id="@+id/tv"
                      android:text="对比度"
                      android:gravity="right"
                      android:textColor="#ffffff"/>
            <SeekBar

                      android:layout_marginTop="10dip"
                      android:layout_toRightOf="@id/tv"
                      android:id="@+id/duibiSeekBar"
                      android:layout_width="210dip" 

                      android:layout_height="wrap_content" 
                      android:minHeight="6dip"
                      android:maxHeight="6dip"
                      android:paddingLeft="15px"
                      android:paddingRight="5px"
                      android:max="100"
                      android:progress="50"
                      android:thumbOffset="3px"
                      android:progressDrawable="@drawable/seekbar_progress"
                      android:thumb="@drawable/seekbarthumb"/>

       </RelativeLayout>

    </LinearLayout>

If you press STR+SPACE, does the auto-complete dialog show up? If so, you might want to reduce the delay to 0.

Otherwise, restoring the Editors defaults might also help.

If nothing else works, you can create a new Workspace and import your old projects.