我正在launcher.xml使用Failed to instantiate on or more classes错误：The following classes could not be instantiated
-com.android.launcher3.Hotseat (Open Class, Show Exception, Clear Cache)
-com.android.launcher3.DeleteDropTarget (Open Class, Show Exception, Clear Cache)
-com.android.launcher3.InfoDropTarget (Open Class, Show Exception, Clear Cache)
-com.android.launcher3.Workspace (Open Class, Show Exception, Clear Cache)
-com.android.launcher3.CellLayout (Open Class, Show Exception, Clear Cache)
-com.android.launcher3.Pageindicators.PageIndicatorLinecaret (Open Class, Show Exception, Clear Cache)
-com.android.launcher3.UninstallDropTarget (Open Class, Show Exception, Clear Cache)
Tip: Use View.isInEditMode() in your custom views to skip code or show sample data when shown IDE
If this in an unexpected error you can try to build the project, then manually refresh the layout
Exception Details
java.lang.ClassNotFoundException: android.appwidget.AppWidgetHost
(Copy stack to clipboard)
Layout fidelity warning和The graphics preview in the layout editor may not be accurate:
-Paint.setShadowLayer is not supported (Ignore for this session)
正在出现（禁用IDE以显示布局）
[Wed Apr 26 02:40:13 2017] [error] [client x.x.x.x] script not found or unable to stat: /var/www/cgi-bin/wa.exe
[Wed Apr 26 02:40:13 2017] [error] [client x.x.x.x] script not found or unable to stat: /var/www/cgi-bin/wa.exe
[Wed Apr 26 02:40:14 2017] [error] [client x.x.x.x] script not found or unable to stat: /var/www/cgi-bin/whois.cgi
[Wed Apr 26 02:40:14 2017] [error] [client x.x.x.x] script not found or unable to stat: /var/www/cgi-bin/whois.cgi
[Wed Apr 26 02:40:36 2017] [error] [client x.x.x.x] script '/var/www/cgi-bin/contact.php' not found or unable to stat
[Wed Apr 26 02:40:38 2017] [error] [client x.x.x.x] script not found or unable to stat: /var/www/cgi-bin/counter.exe
[Wed Apr 26 02:40:58 2017] [error] [client x.x.x.x] script not found or unable to stat: /var/www/cgi-bin/hosting
[Wed Apr 26 02:41:02 2017] [error] [client x.x.x.x] script '/var/www/cgi-bin/form.php' not found or unable to stat
[Wed Apr 26 02:41:05 2017] [error] [client x.x.x.x] script '/var/www/cgi-bin/comments.php' not found or unable to stat
[Wed Apr 26 02:41:08 2017] [error] [client x.x.x.x] script not found or unable to stat: /var/www/cgi-bin/projects_site
[Wed Apr 26 02:41:46 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:41:47 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:41:47 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:41:49 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:41:50 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:41:50 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:41:51 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:41:51 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:41:51 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:41:52 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:43:02 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:43:03 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:43:03 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:43:04 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:43:04 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:43:04 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:43:05 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:43:05 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:43:06 2017] [error] [client x.x.x.x] Invalid Content-Length
[Wed Apr 26 02:43:20 2017] [error] [client x.x.x.x] Client sent malformed Host header
[Wed Apr 26 02:43:20 2017] [error] [client x.x.x.x] Client sent malformed Host header
[Wed Apr 26 02:43:31 2017] [error] [client x.x.x.x] Client sent malformed Host header
[Wed Apr 26 02:43:31 2017] [error] [client x.x.x.x] Client sent malformed Host header
[Wed Apr 26 02:43:31 2017] [error] [client x.x.x.x] Client sent malformed Host header
我尝试过：清除缓存，刷新布局，使缓存无效并重新启动，通过打开它们来确保手动存在类
欢迎任何所需的其他信息
提前致谢