在drawable下
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<solid android:color="#333"
/>
<corners android:topLeftRadius="35px"
android:bottomLeftRadius="35px"
android:bottomRightRadius="35dp"
android:topRightRadius="35px"
/>
</shape>
设置成背景