C5/app/src/main/res/drawable/darkgrey_round_button.xml

<?xml version="1.0" encoding="UTF-8"?>
<shape
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <!-- 填充的颜色 -->
    <solid android:color="@color/darkgrey" />
    <!-- 圆角的半径 -->
    <corners android:radius="@dimen/px10dp" />
</shape>