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Questions tagged [viewmodel]

A view model or viewpoints framework is a framework which defines a coherent set of views to be used in the construction of an architecture. A view is a representation of a whole system from the perspective of a related set of concerns.

A view model or viewpoints framework in systems engineering, software engineering, and enterprise engineering is a framework which defines a coherent set of views to be used in the construction of a system architecture, software architecture, or enterprise architecture. A view is a representation of a whole system from the perspective of a related set of concerns.

Source: http://en.wikipedia.org/wiki/View_model

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Jetpack Compose - Unresolved reference: observeAsState

I'm learning Jetpack Compose and I was trying to make a View Model for my @Composable. In documentation (https://developer.android.com/codelabs/jetpack-compose-state#3) for observing state changes in composable they use observeAsState but in my…
Valentin
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'by viewModels()' Kotlin property delegate unresolved reference

I'm trying to implement viewmodel with kotlin. First I added the needed dependecies: implementation 'androidx.appcompat:appcompat:1.1.0' implementation 'androidx.core:core-ktx:1.2.0' // ViewModel implementation…
Toni Joe
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how to instantiate ViewModel In AndroidX?

I want to initialize ViewModel in Activity using androidx library I have tried what documentation says but it is not working. the ".of" is not resolved. import androidx.appcompat.app.AppCompatActivity import android.os.Bundle import…
Nurseyit Tursunkulov
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How to bind WPF button to a command in ViewModelBase?

I have a view AttributeView that contains all sorts of attributes. There's also a button that when pressed, it should set the default values to the attributes. I also have a ViewModelBase class that is a base class for all ViewModels I have. The…
kor_
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ArgumentMatchers.any must not be null

I am trying to test ViewModel to make sure livedata gets updated correctly. However when using ArgumentMatchers.any() it fails with IllegalStateException saying: ArgumentMatchers.any(mViewModel.CountSubscriber::class.java) must not be…
Ana Koridze
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Do i need to create automapper createmap both ways?

This might be a stupid question! (n00b to AutoMapper and time-short!) I want to use AutoMapper to map from EF4 entities to ViewModel classes. 1) If I call CreateMap() then do I also need to call CreateMap
BlueChippy
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ValidateInput(false) vs AllowHtml

I have a form that is used to create a memo, to do that I am using a rich text editor to provide some styling, this creates html tags in order to apply style. When I post that text, the mvc throws an error to prevent potentially dangerous scripts,…
EricGS
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ASP.Net MVC and state - how to keep state between requests

As a fairly experienced ASP.Net developer just recently starting using MVC, I find myself struggling a bit to change my mindset from a traditional "server control and event handler" way of doing things, into the more dynamic MVC way of things. I…
TMan
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MVVM and collections of VMs

A common senario: A model with a collection of item models. E.g a House with a collection of People. How to structure this correctly for MVVM - particulary with regard to updating the Model and ViewModel collections with additions and deletes? Model…
Ricibob
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How to get an Instance of ViewModel in activity in 2020/21?

I am new to the mvvm pattern. I created a ViewModel for the main activity. Now I want to get an instance of the ViewModel in the main activity. Most Tutorials and answers here on Stackoverflow suggest using ViewModelProviders.of(..., but this is…
Gerke
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How to write a ViewModelBase in MVVM

I'm pretty new in WPF programming environment. I'm trying to write a program out using MVVM design pattern. I've did some studies and read up some articles related to it and many of a time I came across this thing called ViewModelBase I know what…
DriLLFreAK100
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Should a user control have its own view model?

I have a window made up of several user controls and was wondering whether each user control have its own view model or should the window as a whole have only one view model?
AwkwardCoder
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WPF: how to signal an event from ViewModel to View without code in codebehind?

I have quite simple (I hope :)) problem: In MVVM, View usually listens on changes of ViewModel's properties. However, I would sometimes like to listen on event, so that, for example, View could start animation, or close window, when VM signals.…
Tomáš Kafka
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ViewModel in Kotlin: Unresolved Reference

I am trying to implement ViewModel in a 100% Kotlin app. Every piece of documentation I can find says I want to use this to get the ViewModel instance: ViewModelProviders.of(this).get(CustomViewModel::class.java) According to the docs, I should be…
RedBassett
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ASP.NET MVC - Database entities or ViewModels?

I am currently working on an ASP.NET MVC project. Some developers on the team want to bind the auto-generated database entities directly to the Views. Other developers want to create tailor-made ViewModel's and bind those to the Views. Objectively,…
Alex York
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