How to help you?

[Evangelink]

@TysonMN @cmeeren Thank you for the time you are taking to help me use your framework in the best way!

Is there a way (bug, feature, doc, coffee, open collective ...) for me to contribute back this time?

[TysonMN]

You are welcome @Evangelink. And thank you for your willingness to contribute back :D

I would primarily love help with the samples. There are several ways this can be done.

For the most part, each sample focuses on a particular (type of) binding. There are two issues with this.

First, I am in the middle of making the binding API more composable (c.f. #263 and other issues with "composable" in the title). As this work progresses, the existing samples can be refined and expanded to match the new API.

Second, @cmeeren and I want to have samples that with a purpose different than demonstrating how to use a particular (type of) binding.

• We want samples that show different project structures (c.f. Add samples demonstrating other project structures #325).
• We also discussed (though I can't remember where) adding samples that show how to integrate with different third party libraries including DevExpress and Telerik. Not exactly sure how this would work if permanently free versions are not available. It could be worth asking such companies how we can help each other.
• Maybe there could also a similar sample just for WPF (and include things like the key bindings you shared in Enrich event bindings example with KeyBinding #336).
• One missing feature is multiselect How to make ListBox multiselect work with Elmish.WPF #188. As I recall, that issue contains work arounds people are currently using. It would be nice to create a multiselect sample that implements all of those workarounds. Then when we eventually add first-class support for multiselect, that sample can be modified accordingly.
• I want to expand the Sticky sample with a SubModelOpt binding that uses transition animation and stickiness as described in the documentation (c.f. Composable stickiness #340).
• I want to better understand adorners (c.f. How to fire an adorner with PreviewMouseLeftButtonUp in a ListView #292). It would be great to have a sample that uses an adorner or two in some standard ways.

As I implement the composable binding API, I want code that tests those bindings. I don't mind starting with manual testing via the samples. That is why I think improving the samples is the most important. Eventually we should have automated tests. My guess is that users of Elmish.WPF would be better at creating good samples than creating good tests. At the same time, I don't want to stop anyone from trying to improve the tests.

Lastly, we don't have an project collective, but I recently made it possible to sponsor me on GitHub.

[TysonMN]

Another collection of samples could be focused on patterns.

• There is the command message (CmdMsg) pattern for making it possible to test the correctness of the commands returned from update. To a first-order approximation, pure functions or functional design is intrinsically testable. However, how can you test a function with signature int -> (unit -> unit) (where we think of the output as a function with type unit -> unit even though the parentheses are not necessary)? Only by executing the returned impure function. So instead, the CmdMsg pattern allows the separation of "what" (which is pure) and "how" (which is impure).
• There is the out message (OutMsg) pattern and its continuation with the translator pattern to support child-to-parent communication (c.f. Attempting to emulate C# CollectionViewSource among three views of the same list. #300 (comment) and its use in the SubModelSeq sample).

FileDialogs is a sample that does not demonstrate a particular binding. Instead, it shows how to do a common WPF thing (loading and saving a file), especially that the Elmish dispatch loop, which Elmish.WPF executes on the UI thread, continues to work even when a dialog is open. I am not sure where this samples belongs. Maybe in a sample generally about WPF with your key bindings.

[poroburu]

We also discussed (though I can't remember where) adding samples that show how to integrate with different third party libraries including DevExpress and Telerik. Not exactly sure how this would work if permanently free versions are not available. It could be worth asking such companies how we can help each other.

Syncfusion has a community licence for it's controls: "Companies and individuals with less than $1 million USD in annual gross revenue and 5 or fewer developers."

https://www.syncfusion.com/products/communitylicense

[TysonMN]

Closing this issue in favor of #419.

Also, I am trying to make it easier to help by creating issues that I think are more accessible.