<!-- 原来是这样 --> < androidx.constraintlayout.widget.ConstraintLayoutxmlns: android= " http://schemas.android.com/apk/res/android" xmlns: app= " http://schemas.android.com/apk/res-auto" xmlns: tools= " http://schemas.android.com/tools" android: id= " @+id/main" android: layout_width= " match_parent" android: layout_height= " match_parent" tools: context= " .activity.MainActivity" > < Buttonandroid: id= " @+id/btn_go_test" android: layout_width= " wrap_content" android: layout_height= " wrap_content" android: text= " 前往测试" /> </ androidx.constraintlayout.widget.ConstraintLayout> <!-- 修改成这样 --> < androidx.constraintlayout.widget.ConstraintLayoutxmlns: android= " http://schemas.android.com/apk/res/android" xmlns: app= " http://schemas.android.com/apk/res-auto" xmlns: tools= " http://schemas.android.com/tools" android: id= " @+id/main" android: layout_width= " match_parent" android: layout_height= " match_parent" tools: context= " .activity.MainActivity" > < Buttonandroid: id= " @+id/btn_go_test" android: layout_width= " wrap_content" android: layout_height= " wrap_content" android: text= " 前往测试" app: layout_constraintBottom_toBottomOf= " parent" /> </ androidx.constraintlayout.widget.ConstraintLayout> 对上述布局代码进行修改之后，Android Studio 出现如下错误信息，同时无法预览布局 com.intellij.openapi.diagnostic.RuntimeExceptionWithAttachments: Access from Event Dispatch Thread (EDT) is not allowed; see https://jb.gg/ij-platform-threading for details Current thread: Thread[#57,AWT-EventQueue-0,10,main] 254734910 (EventQueue.isDispatchThread()=true) SystemEventQueueThread: (same)问题原因 这个错误是 Android Studio 的一个 Bug，与布局代码本身无关 处理策略 清理项目（Clean Project），即可正常预览布局 