Draft: Do not show temporary line object in tree (additional)

#13778 introduced `self.obj.ViewObject.ShowInTree = False` to hide the temporary object. But objects that are hidden in the tree are displayed in the tree when they are selected in the 3D view. This selection occurs during commands that take more than 2 points. The solution is to change `self.obj.ViewObject.Selectable` on mouse button up/down.

Fixes #13700.

src/Mod/Draft/draftguitools/gui_lines.py

@@ -95,12 +95,19 @@ class Line(gui_base_original.Creator):
         """
         if arg["Type"] == "SoKeyboardEvent" and arg["Key"] == "ESCAPE":
             self.finish()
-        elif arg["Type"] == "SoLocation2Event":
+            return
+        if arg["Type"] == "SoLocation2Event":
             self.point, ctrlPoint, info = gui_tool_utils.getPoint(self, arg)
             gui_tool_utils.redraw3DView()
-        elif (arg["Type"] == "SoMouseButtonEvent"
-              and arg["State"] == "DOWN"
-              and arg["Button"] == "BUTTON1"):
+            return
+        if arg["Type"] != "SoMouseButtonEvent":
+            return
+        if arg["State"] == "UP":
+            self.obj.ViewObject.Selectable = True
+            return
+        if arg["State"] == "DOWN" and arg["Button"] == "BUTTON1":
+            # Stop self.obj from being selected to avoid its display in the tree:
+            self.obj.ViewObject.Selectable = False
             if arg["Position"] == self.pos:
                 self.finish(cont=None)
                 return
@@ -219,6 +226,7 @@ class Line(gui_base_original.Creator):
 
     def drawSegment(self, point):
         """Draws new line segment."""
+
         import Part
         if self.planetrack and self.node:
             self.planetrack.set(self.node[-1])
@@ -229,6 +237,7 @@ class Line(gui_base_original.Creator):
             newseg = Part.LineSegment(last, point).toShape()
             self.obj.Shape = newseg
             self.obj.ViewObject.Visibility = True
+            self.obj.ViewObject.ShowInTree = False
             if self.isWire:
                 _toolmsg(translate("draft", "Pick next point"))
         else:
@@ -238,6 +247,7 @@ class Line(gui_base_original.Creator):
                 newseg = Part.LineSegment(last, point).toShape()
                 newshape = currentshape.fuse(newseg)
                 self.obj.Shape = newshape
+
             _toolmsg(translate("draft", "Pick next point"))
 
     def wipe(self):
@@ -245,6 +255,7 @@ class Line(gui_base_original.Creator):
         if len(self.node) > 1:
             # self.obj.Shape.nullify()  # For some reason this fails
             self.obj.ViewObject.Visibility = False
+            self.obj.ViewObject.ShowInTree = False
             self.node = [self.node[-1]]
             if self.planetrack:
                 self.planetrack.set(self.node[0])