MVVM | Model View View-Model in Python

You can use Prism. Intall package Prism.Core then Install-Package Microsoft.Xaml.Behaviors.Wpf -Version 1.1.31 packages in your project, in your xaml declare namespace as - xmlns:i="http://schemas.microsoft.com/xaml/behaviors"

I was able to get it resolved, but the solution is...hacky.

So, apparently, Google Apps Script exports only what is in globalThis of a project: just the functions and variables. No classes, no constants, ...

Probably has a lot to do with how ES6 works, with its globalThis behavior. One can see that in action, by creating a dummy function, a dummy variable, and a dummy class in their local developer console:

You can download and store the Image in your ViewModel asynchronously, or using the download complete event for example like this:

Or is it mandatory that a module has a screen?

No, of course not, modules have nothing to do with views or view models. They are just a set of registrations with the container.

what would be the best way to create the instance?

Let the container do the work. Normally, you have (at least) one assembly that only contains public interfaces (and the associated enums), but no modules. You reference that from the module and register the module's implementations of the relevant interfaces withing the module's Initialize method. Some other module (or the main app) can then have classes that get the interfaces as constructor parameters, and the container will resolve (i.e. create) the concrete types registered in the module, although they are internal or even private and completely unknown outside the module.

This is as loose a coupling as it gets if you don't want to sacrifice strong typing.

is there a way to get rid of that var searcher = containerProvider.Resolve(); and a better way to achieve this?

You can skip the var searcher = part :-) But if the HotfixSearcher is never injected anywhere, it won't be created unless you do it yourself. OnInitialized is the perfect spot for this, because it runs after all modules had their chance to RegisterTypes so all dependencies should be registered.

If HotfixSearcher is not meant to be injected, you can also drop IHotfixSearcher and resolve HotfixSearcher directly:

i want to know what is the best and simplest method to create window from ViewModel in MVVM pattern

"The best", "the simplest" are very subjective concepts.
For some, a simple implementation may be considered difficult by someone.

This topic is very large, and for a detailed answer to such a question, you will need to write a thick textbook.
Therefore, in short, general concepts, and an example of a possible implementation.

From the ViewModel's point of view, it cannot "know" what a Window is. So asking the question "How should a VM create a Window?" - it is not correct.
The question should be asked like this: "How does the VM call an external dialogue?".
How this dialog will be implemented (WPF Window, Form or Console Input) for the VM does not matter.
A dialog is, in fact, a delegate to a method that returns a dialog result.
In the simplest case, the diaolog's result is just a bool (success / failure).
Let's say OpenFileDialog.ShowDialog returns Nullable .
In more complex cases, an enumeration is returned. Sample MessageBox.
What kind of dialogue result you need depends on the conditions of your task.

Suppose if this is an element editing dialog, then it receives an element for editing in its parameters, and it can return bool: true - editing is completed and its results need to be saved, false - editing cancellation.

Gets the ViewModel delegate, usually at the time of its creation. This is called dependency injection.
A typical place for Dependency Injection is App.

An example will link to your previous topic WPF MVVM binding command to Datacontext inside Datagrid

In a Code-Behind, I could done something like this:

Take a closer look at your XAML.
You have a binding set in the CommanParameter property.
The binding instance is empty - this means that the binding occurs to the DataContext of the element in which it is specified.
Hence, in the command parameter, you will get this Data Context.

The solution you're looking for depends on how your app is designed. There are several things you can try out:

• Keep your app modularized - as @ADM mentioned split your repository into smaller
• Move live data out of repository - it is unnecessary to keep live data in a repository (in your case singleton) for the entire app lifecycle while there might be only few screens that need different data.
• That's being said - keep your live data in view models - this is the most standard way of doing. You can take a look at this article that explains Retrofit-ViewModel-LiveData repository pattern
• If you end up with complicated screen and many live data objects you can still map entities into screen data representation with events / states /commands (call it as you want) which are pretty well described here. This way you have single LiveData and you just have to map your entities.

Additionaly you could use coroutines with retrofit as coroutines are recomended way now for handling background operations and have Kotlin support if you wanted to give it a try.

Also these links might halpe you when exploring different architectures or solutions for handling your problem architecture-components-samples or architecture-samples (mostly using kotlin though).

I guess your main issue is with Button title getting changed on scroll, so i am posting a solution for that.

Note-: Below code doesn’t follow MVVM.

Controller-:

Modify your @objc private func didTapButton(). Instead of