Android/app/src/main/res/layout/pay_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    android:gravity="center_horizontal"
    android:background="#FFFFFF">



    <fragment
        android:id="@+id/fragment"
        android:name="com.yihucha.hbyhc.alipay.ExternalFragment"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        tools:layout="@layout/pay_external" />

</LinearLayout>