005-Android studio Namespace 'tools' is not bound！！

例如：

<activity
android:name="com.google.android.gms.ads.AdActivity"
android:theme="@android:style/Theme.NoTitleBar.Fullscreen"
tools:replace="android:theme"
/>

添加：

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

at the top of the manifest (or activity).

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.mypackage"
xmlns:tools="http://schemas.android.com/tools">