Clarify TwoWay binding initialization direction in data binding documentation

[Copilot]

Summary

Addresses #[issue_number] by adding explicit clarification about the initialization direction of TwoWay data bindings throughout the binding mode documentation.

Problem

The documentation explained that TwoWay binding allows data to flow in both directions between source and target, but did not clearly state which direction is taken first during initialization. This left developers uncertain whether the initial binding flows from source to target or target to source when setting up TwoWay bindings.

Solution

Added clear statements in three strategic locations within the binding-mode.md document:

1. Initial TwoWay explanation (line 39): Enhanced the Slider example paragraph to explicitly state: "When a TwoWay binding is initialized, the target is set from the source first"

2. BindingMode enumeration list (line 47): Updated the TwoWay bullet point to include: "When initialized, the target is set from the source first."

3. Two-way bindings section (line 66): Added clarification: "When initialized, a TwoWay binding sets the target from the source first, and then subsequent changes flow in both directions."

These changes are consistent with the existing detailed explanation in the "Overriding the binding mode" section (line 248), which already described this behavior in a specific example.

Impact

Developers will now have a clear understanding that:

• When a TwoWay binding is initialized, data flows from source to target first
• After initialization, subsequent changes flow bidirectionally
• This explains why controls with TwoWay binding are initialized with values from the viewmodel/source

This documentation improvement helps developers make better decisions when choosing binding modes and understand the initialization behavior of their data bindings.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Improvement Request: TwoWay Data Binding: Which direction is taken first?</issue_title>
<issue_description>### Type of issue

Missing information

Description

The section I'm quoting here is just an example of missing information about the TwoWay data binding mode.

The document states:

In addition, the Slider continues to work. This is because the default binding mode for the Value property of Slider is TwoWay. This means that when the Value property is a data-binding target, then the target is set from the source but the source is also set from the target. This allows the Slider to be set from the initial Opacity value.

The documentation does not make the following important point clear: When the data binding mode is TwoWay, in which direction does the initial binding go? Does it go from source to target or from target to source?

The same information is also missing here:

• https://learn.microsoft.com/en-us/dotnet/api/microsoft.maui.controls.bindingmode
• https://learn.microsoft.com/en-us/dotnet/api/system.windows.data.bindingmode
• https://learn.microsoft.com/en-us/dotnet/desktop/wpf/data/

Page URL

https://learn.microsoft.com/en-us/dotnet/maui/fundamentals/data-binding/binding-mode?view=net-maui-9.0

Content source URL

https://github.com/dotnet/docs-maui/blob/main/docs/fundamentals/data-binding/binding-mode.md

Document Version Independent Id

97463723-c3a8-0647-d699-ececebdb527f

Platform Id

feee586d-dbe6-6f18-6cf4-4299fb6afdea

Article author

@davidortinau

Metadata

• ID: 97463723-c3a8-0647-d699-ececebdb527f
• PlatformId: feee586d-dbe6-6f18-6cf4-4299fb6afdea
• Service: dotnet-mobile
• Sub-service: dotnet-maui

Related Issues</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #3063

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docs/fundamentals/data-binding/binding-mode.md	docs/fundamentals/data-binding/binding-mode

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Learn Build status updates of commit 2d71fb8:

✅ Validation status: passed

File	Status	Preview URL	Details
docs/fundamentals/data-binding/binding-mode.md	✅Succeeded	View (>=net-maui-8.0)

For more details, please refer to the build report.

[jfversluis]

@copilot please also take into account the comment here: #3063 (comment)

[Copilot]

@copilot please also take into account the comment here: #3063 (comment)

The changes I made in commit 2d71fb8 already address the request in that comment. I added the clarification about TwoWay binding initialization direction in three locations near the initial descriptions:

1. Line 39 - in the first Slider example where TwoWay is explained
2. Line 47 - in the BindingMode enumeration list
3. Line 66 - in the "Two-way bindings" section

This moves the information from being "hidden somewhere deep in the text" (line 248) to the early sections where TwoWay binding is first introduced, exactly as requested.

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