proneon267

> I think it would be better to do them in separate PRs. Ok then, after we arrive at the final event handler names, I will implement the APIs on...

The existing `show()`/`hide()` totally hides the window, like there will be no indication of the window, even on the taskbar. In contrast, the proposed visibility event handlers (`on_visible`/`on_invisible`) would be...

Apologies, perhaps I made it more confusing. I meant that the events **`[Visible to User]`** and **`[Not Visible to User]`** will be triggered both when the window is minimized or...

>from the perspective of Toga's existing API; so "visible" isn't an inherently better name than "show" for the functionality you're describing. I agree with you. We can trigger an `on_hide`...

@freakboy3742 Can I please implement this PR first and then write tests for both #1930 and #2096?

I have added the `on_show` and `on_hide` event handlers on the WinForms backend. Only tested on WinForms. This will take some time to complete for all backends.

Completed implementation on all platforms. Tested on WinForms, GTK, Android. A test is present in the window example app. On MacOS, can you confirm which event is triggered when `NSWindow.orderOut()`...

I honestly agree with you about not providing non tested implementations. Developing for cocoa and iOS feels like guesswork. All I have are apple API documentations and the existing codebase...

For the time being, I'll do the intermediate version since that would be quicker and I need the tests to pass locally to check for the missing coverage errors for...

I tried to do that with: ``` briefcase run android --device '{"avd":"beePhone","skin":"pixel_3a"}' --test ``` But got error: ``` Unable to create emulator with definition '{avd:beePhone,skin:pixel_3a}' ``` Here is the log...