即使在PowerBuilder应用程序中按下关闭按钮后，窗口也不会关闭

Question

在使用PFC的PB 11.5应用程序中，我有一个响应窗口，经过一些随机的步骤后，即使按下关闭按钮后窗口也不会关闭，并允许使用该窗口中的所有其他选项。按下关闭后它甚至允许访问其他背景窗口。我在这个窗口中使用了外部控件来读取文档。 成功和失败时.dbg文件的内容如下所示。

成功的活动：

Executing event +CLICKED for class CB_CLOSE, lib entry W_DOCUMENT_VIEW
        Executing instruction at line 2
        Executing class function CLOSE for class SYSTEMFUNCTIONS, lib entry _TYPEDEF
          Executing system dll function
          Executing event +CLOSEQUERY for class W_DOCUMENT_VIEW, lib entry W_DOCUMENT_VIEW
            Executing instruction at line 1
            Executing object function +CLOSEQUERY for class W_RESPONSE, lib entry W_RESPONSE
              Executing instruction at line 1
              Executing object function +CLOSEQUERY for class PFC_W_RESPONSE, lib entry PFC_W_RESPONSE
                Executing instruction at line 34
                Executing instruction at line 36
                Executing instruction at line 117
              End class function +CLOSEQUERY for class PFC_W_RESPONSE, lib entry PFC_W_RESPONSE
              Executing instruction at line 1
              Executing instruction at line 2
              Executing instruction at line 6
              Executing instruction at line 7
            End class function +CLOSEQUERY for class W_RESPONSE, lib entry W_RESPONSE.......

失败：

Executing event +CLICKED for class CB_CLOSE, lib entry W_DOCUMENT_VIEW
            Executing instruction at line 2
            Executing class function CLOSE for class SYSTEMFUNCTIONS, lib entry _TYPEDEF
              Executing system dll function
            End class function CLOSE for class SYSTEMFUNCTIONS, lib entry _TYPEDEF
            Executing instruction at line 3
          End event +CLICKED for class CB_CLOSE, lib entry W_DOCUMENT_VIEW