如圖所示點選2以後可以看到如下錯誤
failed to load AppCompat ActionBar with unkNown error Android Studio中layout xml檔案無法預覽報錯... 
failed to load AppCompat ActionBar with unkNown error Android Studio中layout xml檔案無法預覽報錯... failed to load AppCompat ActionBar with unkNown error Android Studio中layout xml檔案無法預覽報錯... 解決方法如下
failed to load AppCompat ActionBar with unkNown error Android Studio中layout xml檔案無法預覽報錯... failed to load AppCompat ActionBar with unkNown error Android Studio中layout xml檔案無法預覽報錯... 轉載于:https://www.cnblogs.com/heamin/p/10870886.html
