Add a preview in settings

[OlenaTatarintseva]

Edited as per #25 (comment):

When settings are changed, particularly the logo upload, add two previews of what QR codes will look like. This allows admins to check whether the codes will look as intended. In particular, it may not be obvious from the start that there is a default logo, and that uploading just a single format type will not have an impact on all QR codes! A preview would make this more apparent.

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Hello,

Thanks for your work on this plugin.

It would be nice to add the QR code image reloading on format selecting. It is not clear for user, how it will looks like, when he/she is trying to download the png file. The image on png file could be different, because there is the possibility in the plugin settings to use different image for each format.

Best regards,
Olena Tatarintseva

[Dagefoerde]

Hi, thanks for sharing your idea. However, I would strongly suggest using logo images that look identical, regardless of the format. The case that you describe sounds to me like the plugin was misconfigured by using different images. In the browser, we strictly use the SVG format as it offers the best resolution in any environment.

Your suggestion leads to my idea that we could show a preview while configuring the block so that an administrator can see whether both images actually look identical. What do you think?

[OlenaTatarintseva]

I think that's a good idea, especially when adding an image, I've noticed that the .svg filemanager holds 'default' image that is 'hidden', so when the admin/teacher adds a .png image, he may not be aware of the fact that .svg already exists and it's different. I hope this makes sense.

[Dagefoerde]

It does make sense indeed. Thanks for your feedback! I took the liberty of changing title and description of the issue to reflect this.

We will put this on our backlog. As usual, please feel free to help. If you can provide a patch, please create a pull request that we will be happy to review. Thank you very much.