I have a sort of note-taking app I’m putting together. It has a horizontal BoxLayout which contains an image and another BoxLayout (which happens to be vertical). This embedded BoxLayout contains a TabbedPanel.

I want to change the image in the main BoxLayout whenever the user selects a different tab in the embedded BoxLayout.

I’m not sure what to do in the on_release() method of each TabbedPanelItem in order to get the different images to display.

Currently I have the layout working the way I want up to the point of displaying the image for the first (default) tab.

Here is my code:

• main.py
• layouttest.kv

In the KV code, I have set the source of the Image to app.leftImage. In the 3 on_release() handlers, I set app.leftImage to the correct image. But that doesn’t change what is displayed.

There is probably something simple that I am not understanding, but I am new to Kivy programming, so please answer with sufficient detail for a newbie to grasp.