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Our take on the April update to Power BI (announced on May 6th!)
Part three of a five-part series of blogs

It was announced 6 days after the end of the month, but the April 2020 update to Power BI was worth waiting for - if only for the fact that you can now select visuals by clicking and dragging with the mouse. See our take on the new features in this update in the latest in our series of monthly update blogs.

  1. April 2020 update to Power BI
  2. Three significant changes to your everyday Power BI use
  3. Custom theme editor (this blog)
  4. Other changes in the April 2020 Power BI update
  5. Features waiting in preview

We've been creating our idiosyncratic monthly blogs on Power BI updates since November 2016, and also deliver online and classroom Power BI courses.

Posted by Andy Brown on 09 May 2020

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Custom theme editor

This feature has been in preview for a while, but has now seen the light of day.  If you haven't created a custom theme, you should - and it's now MUCH easier to do so.

What a theme is

Here's a section of a theme I've created called wiseowl (it is written in a format called JSON, which stands for JavaScript Object Notation, should you be interested):

Wise Owl theme

This section of the theme shows that the default font will be 14 point dark brown, and the default title will be centre-justified and appear in white on a dark brown background.


If I apply this theme, this is what I get:

Applying a theme

The title appears, by default, exactly as my theme specified.


Themes can thus save you a huge amount of time, by pre-applying a consistent look-and-feel to any report.  However, editing the JSON files above is not a straightforward undertaking!

The new theme editor

Recognising that the JSON format isn't that easy to edit, Microsoft now let you edit a theme using a built-in editor.  First choose the theme you want:

Editing a theme

I've gone for one called City Park, and am about to click on the dropdown arrow to edit it.

Next, choose to customise your theme:

Customise current theme

Choose this option to customise the theme you are currently using.


The theme editor is delightfully easy to use (but - there's always a but - it is just too limited in scope, as I'll explain towards the bottom of this page):

Setting the theme title

Here I've set titles to appear in large red Comic Sans font (which won't be a popular choice, I suspect).

Instantly my visuals change:

Updated visuals

All visuals take the formatting of the new theme.


Saving your changes

To save your current theme (including any changes you've made to it), choose this option:

Saving your current theme

In the themes area of Power BI, choose the option shown.


You can then give your new theme a name:

New theme file name

I've called mine Created for update.json.


Here's what this created:

The created JSON file

The JSON generated by my choices.


What's good and what's bad

On the plus side, the theme editor is delightfully easy to use:

Customising theme colours

If all that you want to do is to change the default colours used by visuals, for example, the theme editor is fantastic.

On the down side, it's all a bit Mickey Mouse.  Here are a couple of the main limitations:

Limitation Notes
Not many properties supported Not only does the theme editor only support a few formatting cards, but for each of these it only supports a small range of properties.  As one example, I like my titles to appear centre-aligned by default, but this isn't something I can set using the theme editor.
No visual-specific settings I like my pie chart labels to appear as just the category names, and the legend to appear at the bottom, but I can't use the theme editor to make any visual-specific changes.

My verdict is that the theme editor is great for basic Power BI users, but for anyone else it's a bit pointless, as to create a proper theme you're going to have to learn to edit JSON files and understand the syntax used anyway.

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