Nine patch image not working on my device?

Question

This is the first time i use nine-patch image on my android app. It so stupit. When I preview on eclipse layout editor, it work. But when I build the application on real device (HTC Inspire 4g, HTC Explorer,...) it's not.

<LinearLayout
                        android:layout_width="0dip"
                        android:layout_height="fill_parent"
                        android:layout_margin="5dp"
                        android:layout_weight="1"
                        android:background="@drawable/shadow_border"
                        android:gravity="center"
                        android:padding="0dip" >

                        <TextView
                            android:id="@+id/itemdetail_textview_price"
                            style="@style/textview_nomalBold"
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:text="$10"
                            android:textColor="#F00"
                            android:textSize="32dp" />

                        <TextView
                            android:id="@+id/itemdetail_textview_originalPrice"
                            style="@style/textview_nomalBold"
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:layout_marginLeft="15dp"
                            android:text="$20"
                            android:textSize="32dp" />
                    </LinearLayout>

Is there any problem here?

UPDATED:

• I am writing the app for Android 2.2 and above.

• My Phones use Android 2.3

Answer 1

I solved it by my self but I don't understand why it works.

In nine-patch, I draw 2 line at the top and the left of image (see 2 black lines at the picture)