[Error] Error parsing XML: unbound prefix

发生该错误的代码：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <com.example.CustomWidget.MyView
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
 
        android:id="@+id/surface"
        android:focusable="true"
        android:focusableInTouchMode="true"
        android:layout_weight="1"/>
 
</LinearLayout>

说明：com.example.CustomWidget is the name of my package and MyView is the name of my class file where I made the custom Widget.

方案：

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

becomes:

xmlns:mynamespace="http://schemas.android.com/apk/res/com.myproject.myprojectname"

Thereafter any custom attribute elements you define for your custom view will be referred to as:

mynamespace:my_defined_attribute="success"

instead of :

android:layout_width="fill_parent"