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Are there any limitations to using One-Time binding in MvvmCross


One-Time binding in MvvmCross is a useful binding mode that transfers values from the ViewModel to the View only once, when the binding source is set. It does not actively monitor changes in the ViewModel, which means it does not update the View if the ViewModel's properties change after the initial binding. Here are some limitations and considerations for using One-Time binding:

1. No Continuous Updates: The primary limitation of One-Time binding is that it does not continuously update the View based on changes in the ViewModel. This makes it less suitable for dynamic data that needs to be reflected in real-time on the UI.

2. Static Data: One-Time binding is best used for static or read-only data that does not change frequently. For example, it is often used for setting static text from language files, as the language selection is typically made once and not changed frequently[1].

3. RecyclerView and Similar Controls: In controls like `MvxRecyclerView`, One-Time bindings may not behave as expected due to view recycling. When the user scrolls through a list, views are recycled and reused, which can cause One-Time bindings to re-fire, effectively behaving like continuous bindings[4]. This can lead to unexpected behavior if not managed properly.

4. Performance Considerations: While One-Time bindings do not monitor changes, they do not inherently introduce performance issues. However, if used extensively in complex layouts or with many bindings, the initial setup might contribute to slower UI rendering times compared to other binding modes[9].

5. Thread Safety: MvvmCross bindings, including One-Time bindings, can be affected by threading issues if not properly managed. For instance, if bindings are executed on a worker thread, it might lead to unexpected behavior unless properly synchronized with the UI thread[5][3].

In summary, while One-Time binding is useful for static data, it is not ideal for dynamic data or scenarios where continuous updates are necessary. Additionally, its behavior in certain UI components like `RecyclerView` requires careful handling to avoid unexpected rebindings.

Citations:
[1] https://www.mvvmcross.com/documentation/fundamentals/data-binding
[2] https://stackoverflow.com/questions/25460030/when-to-use-mvvmcross-data-bindings
[3] https://github.com/MvvmCross/MvvmCross/issues/1545
[4] https://stackoverflow.com/questions/48910503/binding-mode-onetime-in-mvxrecyclerview
[5] https://www.mvvmcross.com/mvvmcross-4.2/
[6] https://github.com/MvvmCross/MvvmCross/issues/29
[7] https://stackoverflow.com/questions/17156368/
[8] https://learn.microsoft.com/en-us/dotnet/maui/fundamentals/data-binding/binding-mode?view=net-maui-9.0
[9] https://github.com/MvvmCross/MvvmCross/issues/1342
[10] https://www.mvvmcross.com/mvvmcross-5-release/