Unable to start activity ComponentInfo{cn.lanol.studykongjian/cn.lanol.studykongjian.MainActivity}: android.view.InflateException: Binary XML file line #11 in cn.lanol.studykongjian:layout/activity_main: Binary XML file line #11 in cn.lanol.studykongjian:layout/activity_main: Error inflating class android.support.v7.widget.Toolbar

经过尝试发现，现在似乎ToolBar不能像书上那样写了。

<android.support.v7.widget.Toolbar
    android:id="@+id/toolBar"
    android:layout_width="match_parent"
    android:layout_height="?attr/actionBarSize"
    android:background="?attr/colorPrimary"
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
    app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />

应该这样写

<androidx.appcompat.widget.Toolbar
    android:layout_width="match_parent"
    android:layout_height="?attr/actionBarSize"
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
    app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />