frameLayout后边的按钮及文本框都不显示？为什么呢？

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout android:orientation="vertical" 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent"
  xmlns:android="http://schemas.android.com/apk/res/android">
  
    <FrameLayout android:id="@+id/relativeLayout1" 
                    android:layout_width="300dip" 
                    android:layout_height="300dip">
       
          <com.ckc.ckccamera.CameraView 
                android:id="@+id/CameraView"
                android:layout_width="300dip" 
                android:layout_height="300dip" 
                android:layout_centerInParent="true" 
                />             <com.ckc.ckccamera.DrawFaceData 
                android:id="@+id/DrawFaceData" 
                android:layout_width="300dip" 
                android:layout_height="300dip" 
                android:layout_centerInParent="true" />
                 </FrameLayout>
       
         <LinearLayout android:orientation="horizontal" 
            android:id="@+id/linearLayout2" 
            android:background="#ff000000" 
            android:visibility="visible" 
            android:layout_width="fill_parent" 
            android:layout_height="wrap_content" 
            android:layout_alignParentBottom="true">
            <Button android:id="@+id/AddButton" 
                android:visibility="visible" 
                android:layout_width="0.0px" 
                android:layout_height="wrap_content" 
                android:text="Add" 
                android:layout_weight="1.0" 
                android:onClick="clickAddButton" />
        <Button android:id="@+id/ResetButton" 
                android:visibility="visible" 
                android:layout_width="0.0px" 
                android:layout_height="wrap_content" 
                android:text="Reset" 
                android:layout_weight="1.0"  />
             <TextView android:id="@+id/FaceData" 
            android:background="#ff000000" 
            android:visibility="visible" 
            android:layout_width="200dip" 
            android:layout_height="200dip" 
            android:singleLine="false" />
        </LinearLayout>
    
</LinearLayout>