Change Spinner DropDown width

I need resize this part size to full display. How can i do this? My adapter: ``` String[] navigations = getResources().getStringArray(R.array.actionBar); ArrayAdapter<String> adapter = new ArrayAdapter<String>( getBaseContext(), R.layout.custom_spinner_title_bar, android.R.id.text1, navigations); adapter.setDropDownViewResource(R.layout.custom_spinner_title_bar); actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_LIST); actionBar.setListNavigationCallbacks(adapter, navigationListener); ``` custom_spinner_title_bar.xml: ``` <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/RelativeLayout1" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="fill_horizontal" android:orientation="vertical" > <TextView xmlns:android="http://schemas.android.com/apk/res/android" android:id="@android:id/text1" android:layout_width="fill_parent" android:layout_height="wrap_content" android:gravity="center" android:padding="5dip" android:textAppearance="?android:attr/textAppearanceMedium" android:textColor="#FFFFFF" /> </RelativeLayout> ```