将is_scanning方法提升为公开可访问

hgdriver/hgdev/hg_scanner.h

@@ -430,14 +430,6 @@ protected:
 
     void adjust_filling_hole(LPSCANCONF conf);
 
-    enum thread_running
-    {
-        THREAD_RUNNING_IDLE = 0,
-        THREAD_RUNNING_USB = 1 << 0,
-        THREAD_RUNNING_IMAGE = 1 << 1,
-    };
-    int is_running(void);   // return thread_running
-
     ////////////////////////////////////////////////////////////////
     // 新增自定义伽玛曲线及扫描区域属性 - 2022-05-05
     bool    custom_gamma_;                  // 为true时，应用custom_gamma_val_阵列调整图像色彩；为false时，保持原来的处理方式
@@ -476,6 +468,14 @@ public:
     bool is_online(void);
     void on_language_changed(void);
 
+    enum thread_running
+    {
+        THREAD_RUNNING_IDLE = 0,
+        THREAD_RUNNING_USB = 1 << 0,
+        THREAD_RUNNING_IMAGE = 1 << 1,
+    };
+    int is_running(void);   // return thread_running
+
 public:
     virtual int start(void);
     virtual int get_image_info(SANE_Parameters* ii, int len);