DividerItemDecoration divider = new DividerItemDecoration(getActivity(),DividerItemDecoration.VERTICAL);
divider.setDrawable(ContextCompat.getDrawable(getActivity(),R.drawable.custom_divider));
mRvSort.addItemDecoration(divider);

其中custom_divider 是：
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">

    <gradient
        android:startColor="@color/decolratiion"
        android:centerColor="@color/decolratiion"
        android:endColor="@color/decolratiion"
        android:type="linear" />
    <size android:height="1dp" />
</shape>