Uno.UI regression: Buttons work erratically

[SuperJMN]

Problem

Given a simple calculator app. The calculator buttons do nothing most of times when they're clicked.

Details

There seems to be a regression in Uno.UI, since there's a version in which things work perfectly and a newer version breaks the correct behavior.

Repro steps

1. Clone the repo at https://github.com/SuperJMN/UnoSimpleCalc/
2. Checkout this commit to be sure the problem is there: ab759ce435683b29ed7882d90e06e5d9544df116 (last commit as 11-06-2019)
3. Run the Web Assembly app. The buttons will work:
4. Update the Uno.UI package to any version between 2.0.512-dev.3446 and 2.0.512-dev.3728
5. Run the Web Assembly app. The buttons will not work or will work erratically.

I did some research to isolate the regression. This is the table of results I have:

As you can see, the last version that worked is 2.0.324-dev.3171 and the first version that doesn't work is 2.0.512-dev.3446. In the middle, the are some version in which the build is broken (denoated by x).

Affected platform(s):

• iOS
• Android
• WebAssembly
• WebAssembly renderers for Xamarin.Forms
• Windows
• Build tasks
• Solution Templates

[dr1rrb]

Version 512 correspond to the merge of #1256 which is "kind-of" related to buttons clicks 😜 I'll try to have a look, but in the meantime, do you have anything in the logs?

[SuperJMN]

Hey @dr1rrb thanks for the quick response! I don't have logs, but maybe @paulovila has more info!

[SuperJMN]

This is the Chrome Console log I gathered.

localhost-1573058769818.log

Please, ignore the "Pressed X" entries. It's a `Console.WriteLine' we added to log when a command executes.

[dr1rrb]

Actually I don't even get the "Pressed X" 😕 (even if I remove the #if __WASM__).

I can see that the "pointerdown" and "pointerup" events are dispatched to the managed code, and we get back the pointer capture / release sequence ... but nothing happen.

[dr1rrb]

Ok so I looked a bit deeper, this is due to the ViewBox : coordinates of the pointer events are "scaled" accordingly, but when in ButtonBase we validate if the pointer was released over the button, the location.<X|Y> might be greater than the Actual<Width|Height> (which are not "scaled").

(BTW: it means that if you always press the top left corner of buttons, it works properly)

[paulovila]

That's a good start, the area of the button is clickable and the hovering is consistent, but the command is not being triggered

[dr1rrb]

Hi @paulovila, on my side I don't have any issue with the command not being triggered, at least on WASM. If you have to opportunity to test with this fix #2091 and let me know if it works also for you.

[paulovila]

Hi @dr1rrb thanks, still no joy, I checked out dev/dr/TouchTrans and overwrote Uno.UI package , still the command doesn't get fired

[dr1rrb]

Hi @dr1rrb thanks, still no joy, I checked out dev/dr/TouchTrans and overwrote Uno.UI package , still the command doesn't get fired

Hi @paulovila , I just tried:

1. git checkout master
   git pull
   git clean -fdx

2. Open the "unoSimpleCalc.sln" in VS 2019
3. Manage nuget packages, and install latest dev version of Uno.UI (2.0.512-dev.4021)
4. Run "UnoSimpleCalc.Wasm", and I'm not able to reproduce the issue neither on Firefox, Edge nor Chrome

Are you able to give me more info on how you reproduce it?

Note: I also checked that my nuget update was successful by decompiling bin/debug/netstandard2.0/Uno.UI.dll with ILSpy and validating that the assembly AssemblyInformationalVersion attribute is 2.0.512-dev.4021+Branch.master.Sha.869282ee6c94cfca7e6d25c01f5501bb86bd6ad0.869282ee6c94cfca7e6d25c01f5501bb86bd6ad0

[paulovila]

It's working fine , I've tried in Chrome, and Edge, great job!

[dr1rrb]

Great news, then I close this issue 😀

[SuperJMN]

Great work! Thanks!