<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    xmlns:hyman="http://schemas.android.com/apk/res/com.example.dome"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:background="#fff"

    >

<com.example.dome.view.Topbar

    android:layout_width="match_parent"

    android:layout_height="40dp"

    hyman:mtitle="自定义"

    hyman:mtitleTextColor="#123412"

 >

</com.example.dome.view.Topbar>

</RelativeLayout>