Parameters of Shape

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="ring"> <!-- rectangle | line | oval | ring  默认为rectangle-->
    <!-- The radius is used when dang shape="rectangle", which will be overridden by the default 1dp by the following single radius attribute-->
    <corners
        android:bottomLeftRadius="integer"
        android:bottomRightRadius="integer"
        android:radius="integer"
        android:topLeftRadius="integer"
        android:topRightRadius="integer" />
    <gradient
        android:angle="integer"
        android:centerColor="integer"
        android:centerX="integer"
        android:centerY="integer"
        android:endColor="color"
        android:gradientRadius="integer"
        android:startColor="color"
        android:type="linear"
        android:useLevel="false" />

    <padding
        android:bottom="integer"
        android:left="integer"
        android:right="integer"
        android:top="integer" />
    <!--Specify the size, generally used in imageview with scaleType attribute -->
    <size
        android:width="integer"
        android:height="integer" />
    <!-- fill color-->
    <solid android:color="color" />

    <stroke
        android:width="integer"
        android:color="color"
        android:dashGap="integer"
        android:dashWidth="integer" />
  <!-- dash width
    Width between dotted lines -->

</shape>

Come up with an example

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"> <!-- rectangle | line | oval | ring The default is rectangle-->
<!-- The radius is used when dang shape="rectangle", which will be overridden by the default 1dp by the following single radius attribute-->

<gradient
    android:angle="45"
    android:endColor="#805FBBFF"
    android:startColor="#FF5DA2FF" />

<padding
    android:bottom="7dp"
    android:left="7dp"
    android:right="7dp"
    android:top="7dp" />
<corners android:radius="8dp" />
</shape>