[NumberBox] Binding, TwoWay, LostFocust changes the value before losing focus

[AndrewKeepCoding]

Describe the bug

NumberBox with Binding as the following code, when operated by mouse scrolling or UP/Down keys, changes the bound value BEFORE the focus is lost.

<NumberBox Value="{Binding DoubleValue, Mode=TwoWay, UpdateSourceTrigger=LostFocus}" />

NumberBox with x:Bind, changes the bound value AFTER the focus is lost.

<NumberBox Value="{x:Bind ViewModel.DoubleValue, Mode=TwoWay, UpdateSourceTrigger=LostFocus}" />

I understand that xBind the recommended way to do bindings, but I need to use Binding in a DataTemplate when the target data type is unknown.

Steps to reproduce the bug

Use this test app in my repo.

Expected behavior

NumberBox, with the following code, changes the value AFTER the focus is lost.

<NumberBox Value="{Binding DoubleValue, Mode=TwoWay, UpdateSourceTrigger=LostFocus}" />

Screenshots

No response

NuGet package version

WinUI 3 - Windows App SDK 1.5.2: 1.5.240404000

Windows version

No response

Additional context

CheckBox works as expected.

<CheckBox IsChecked="{x:Bind ViewModel.BoolValue, Mode=TwoWay, UpdateSourceTrigger=LostFocus}" />
<CheckBox IsChecked="{Binding BoolValue, Mode=TwoWay, UpdateSourceTrigger=LostFocus}" />

[github-actions]

Hi I'm an AI powered bot that finds similar issues based off the issue title.

Please view the issues below to see if they solve your problem, and if the issue describes your problem please consider closing this one. Thank you!

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• UpdateSourceTrigger on PropertyChanged for NumberBox does not work (#7188), similarity score: 0.82
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• Data-bound value not adjusted to fall into range for NumberBox (#2776), similarity score: 0.74
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