[QGIS-Developer] Remove all rubberbands from the canvas

[Paul Wittle]

Hi Tim,

Thanks for getting back to me. That is a shame because I've already got various versions of what you suggest in my script so I guess I will just have to keep looking for the line that is wrong.

The reason I'm struggling is because I'm using it for drawing polygons and all the examples I find seem to be for rectangles or points. Is there a polygon example anywhere?

It does seem slightly odd that rubber bands can't be removed once the script has lost references to them though. The only way seems to be to close and reopen QGIS but I'm surprised there is not a clear method on canvas().

Thanks,
Paul

---

Hi Paul

AFAIK you need to keep track of all the rubber bands you add and then reset them when you want to clean them up. See some example code here:

https://github.com/inasafe/inasafe/blob/develop/safe/gui/tools/rectangle_map_tool.py#L56

Regards

Tim

On Tue, Sep 22, 2020 at 9:02 AM Paul Wittle < paul.wittle at dorsetcouncil.gov.uk> wrote:

> Hi,
>
>
>
> I’m having an issue with the documentation this morning. I’m writing a
> small python plugin and adding rubberbands to the canvas which is fine
> but for some reason I can’t seem to remove them from the canvas at the end.
>
>
>
> To start with, this is because I’d not put anything in to remove them
> but now I’m using the iface.mapCanvas.scene().removeItem() function
> and they still are present.
>
>
>
> I have two questions really:
>
>    1. I can’t see scene defined in the documentation for QgsMapCanvas; is
>    this something that should be there?
>    2. Is there a way to simply remove all scenes from the canvas?
>
>
>
> Any help would be great 😊
>
> Thanks,
>
>

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