try it
<?xml version="1.0" encoding="utf-8"?> <selector xmlns:android="http://schemas.android.com/apk/res/android"> <item><shape> <stroke android:width="1dp" android:color="#000000" /> <solid android:color="@android:color/transparent" /> <corners android:bottomLeftRadius="4dp" android:bottomRightRadius="4dp" android:topLeftRadius="4dp" android:topRightRadius="4dp" /> </shape></item> </selector>
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