PyGIS remove QgsVertexMarker from scene

Question

I am writing a plugin that includes interaction with the map. Therefore, I use a QgsMapTool. It is possible for a user to mark a point on the map. When the user clicks a red X is drawn on the mapCanvas via QgsVertexMarker.
vertex_marker = QgsVertexMarker(self.canvas)
vertex_marker.setCenter(QgsPoint(map_coordinates['x'], map_coordinates['y']))
vertex_marker.setColor(QColor(255, 0, 0))
vertex_marker.setIconSize(7)
vertex_marker.setIconType(QgsVertexMarker.ICON_X)  # ICON_BOX, ICON_CROSS, ICON_X
vertex_marker.setPenWidth(2)

This is working fine. And the red X's are displayed on the map. But I can't delete the VertexMarker. I am trying to delete the VertexMarker from the scene. I've used something like this:
vertex_items = [ i for i in iface.mapCanvas().scene().items() if issubclass(type(i), qgis.gui.QgsVertexMarker)]
    
for ver in vertex_items:
    if ver in iface.mapCanvas().scene().items():
        iface.mapCanvas().scene().items().remove(ver)
    
iface.mapCanvas().refresh()

Like this I get the used VertexMarker that are visible on the scene. But the remove function somehow doesn't remove the marker from the scene.
Is there another possibility to remove the QgsVertexMarker from the scene?

Martin · Accepted Answer

I found a solution. 
Instead of

iface.mapCanvas().scene().items().remove(ver)

the item has to be deleted directly from the scene:

vertex_items = [ i for i in iface.mapCanvas().scene().items() if issubclass(type(i), qgis.gui.QgsVertexMarker)]

for ver in vertex_items:
    if ver in iface.mapCanvas().scene().items():
        iface.mapCanvas().scene().removeItem(ver)

Henhuy · Answer

For a standalone application (without an interface) [Wien 2.8.1] use:

canvas.scene().removeItem(vertexMarker)

Found in PyQgis Developer Cookbook/ Rubberbands and vertex markers

Rid El Mou · Answer

I am working on a simple plugin that allows to zoom to a specific coordinates and draw a mark with an annotation pop up (image below) :

1st : You have to declare a global List that will contain the markers drawn in the scene:
Markers = []

2nd : Function to delete Marker Point:
def Delete_Marker(canvas):
   canvas = iface.mapCanvas()
   global Markers
   for mark in Markers:
      canvas.scene().removeItem(mark)
   canvas.refresh()

3rd : Draw New marker to the scene:
def Draw_Marker(canvas):
   canvas = iface.mapCanvas()
   # clear the canvas from previous added marker
   Delete_Marker(canvas)
   m = QgsVertexMarker(canvas)
   m.setCenter(pt)
   m.setColor(QColor(255, 0, 0))
   m.setIconSize(10)
   m.setIconType(QgsVertexMarker.ICON_X)
   m.setPenWidth(3)
   # Add the drawn marker to the List of markers   
   Markers.append(m)

PyGIS remove QgsVertexMarker from scene

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