208
votes

Looking at the Google docs for ViewModel, they show the below sample code on how to get a ViewModel:

val model = ViewModelProviders.of(this).get(MyViewModel::class.java)

When using the latest dependency android.arch.lifecycle:extensions:1.1.1 there is no such class ViewModelProviders.

Going to the documentation for ViewModelProviders, I saw a comment saying:

This class was deprecated in API level 1.1.0. Use ViewModelProvider.AndroidViewModelFactory

The problem is, when trying to use ViewModelProvider.AndroidViewModelFactory, cannot find an equivalent of method to get the instance of the ViewModel.

What i tried doing:

ViewModelProvider.AndroidViewModelFactory.getInstance(application).create(PlayerViewHolder::class.java)

Hence the name of the method create, I get a new instance of the ViewModel every-time I call it, which is not what I am after.

Any ideas what is the replacement of deprecated code above?

25
use singleton pattern or change to AndroidXOussema Aroua

25 Answers

46
votes

UPDATE 2020-06-16: Presently ViewModelProviders is deprecated and should no longer be used. This question and answer were from late 2018, when that was not the case. This question and answer are also for the older Architecture Components edition of ViewModelProviders, not the AndroidX edition.


When using the latest dependency android.arch.lifecycle:extensions:1.1.1 there is no such class ViewModelProviders.

Yes, there is. To demonstrate this:

  • Create a new project in Android Studio 3.2.1 (with Kotlin, minSdkVersion 21, "empty activity" template)

  • Add android.arch.lifecycle:extensions:1.1.1 to the dependencies of the app module

This will give you an app/build.gradle like:

apply plugin: 'com.android.application'

apply plugin: 'kotlin-android'

apply plugin: 'kotlin-android-extensions'

android {
    compileSdkVersion 28
    defaultConfig {
        applicationId "com.commonsware.myandroidarch"
        minSdkVersion 21
        targetSdkVersion 28
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation"org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    implementation 'android.arch.lifecycle:extensions:1.1.1'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}

You will then see that library show up in "External Libraries" with that class:

External Libraries

And you will be able to reference that class:

package com.commonsware.myandroidarch

import android.arch.lifecycle.ViewModelProviders
import android.support.v7.app.AppCompatActivity
import android.os.Bundle

class MainActivity : AppCompatActivity() {

  override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)

    val provider = ViewModelProviders.of(this)
  }
}

Going to the documentation for ViewModelProviders, I saw a comment saying: This class was deprecated in API level 1.1.0. Use ViewModelProvider.AndroidViewModelFactory

That comment is underneath the ViewModelProviders.DefaultFactory class entry and refers to that class, not ViewModelProviders:

Documentation Screenshot

Any ideas what is the replacement of deprecated code above?

Use ViewModelProviders.

411
votes

I use lifecycle-extensions 2.2.0 version:

implementation "androidx.lifecycle:lifecycle-extensions:2.2.0" 

It should be work, using ViewModelProvider constructor.

// With ViewModelFactory   
val viewModel = ViewModelProvider(this, YourViewModelFactory).get(YourViewModel::class.java)


//Without ViewModelFactory
val viewModel = ViewModelProvider(this).get(YourViewModel::class.java)

2020/5/15 Update

I find another elegant way to achieve, Android KTX can help

implementation "androidx.fragment:fragment-ktx:1.2.4"
val viewmodel: MYViewModel by viewModels()
val viewmodel: MYViewModel by viewModels { myFactory } //With factory

Ref: https://developer.android.com/reference/kotlin/androidx/fragment/app/package-summary#viewmodels

2020/06/25: corrected the case of the delegate

90
votes

As @FantasyFang mentioned in his answer, use the lastest version for the lifecycle:lifecycle-extensions which in this moment is 2.2.0-alpha03. So you should add in your build.gradle file the following line:

implementation 'androidx.lifecycle:lifecycle-extensions:2.2.0-alpha03' 

For those who are using Java, to solve this, pass those arguments directly to ViewModelProvider's constructor:

MyViewModel viewModel = new ViewModelProvider(this, myViewModelFactory).get(MyViewModel.class);

Or if you don't use a factory, simply use:

MyViewModel viewModel = new ViewModelProvider(this).get(MyViewModel.class);

Without passing your the factory object.

57
votes

Import

Deprecated From:

import androidx.lifecycle.ViewModelProviders;

To:

import androidx.lifecycle.ViewModelProvider;

Using

Deprecated From:

ViewModelProviders.of(this, provider).get(VM::class.java)

To:

ViewModelProvider(this, provider).get(VM::class.java)
54
votes

As of 2.2.0. the lifecycle-extensions has been deprecated. Refer to Google Documentation.

This is the cut from the page:

The APIs in lifecycle-extensions have been deprecated. Instead, add dependencies for the specific Lifecycle artifacts you need.

The new libraries are:

// ViewModel and lifecycle support for java
implementation "androidx.lifecycle:lifecycle-viewmodel:${versions.lifecycle}"
implementation "androidx.lifecycle:lifecycle-livedata:${versions.lifecycle}"

// ViewModel and lifecycle support for kotlin
implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:${versions.lifecycle}"
implementation "androidx.lifecycle:lifecycle-livedata-ktx:${versions.lifecycle}"

The new code for JAVA:

viewModel = new ViewModelProvider(this).get(MyViewModel.class);

Or for Kotlin:

viewModel = ViewModelProvider(this).get(MyViewModel::class.java)
37
votes

Early in 2020, Google have deprecated the ViewModelProviders class, in version 2.2.0 of the androidx lifecycle library.

It's no longer necessary to use ViewModelProviders to create an instance of a ViewModel, you can pass your Fragment or Activity instance to the ViewModelProvider constructor instead.

If you use the code like:

val viewModel = ViewModelProviders.of(this).get(CalculatorViewModel::class.java)

you'll get a warning that ViewModelProviders has been deprecated.

To avoid using deprecated libraries, make the following changes:

  1. In the build.gradle (Module: app) file, use version 2.2.0 of the lifecycle components:

    implementation 'androidx.lifecycle:lifecycle-extensions:2.2.0'
    implementation "androidx.activity:activity-ktx:1.1.0"
    

    If you want to use the ViewModel from a Fragment instead, use

    implementation "androidx.fragment:fragment-ktx:1.2.2"
    

    fragment-ktx automatically includes activity-ktx, so you don't need to specify both in the dependencies.

  2. You need to specify Java 8 in the android section :

    android {
        compileSdkVersion 28
        defaultConfig {
            applicationId "com.kgandroid.calculator"
            minSdkVersion 17
            targetSdkVersion 28
            versionCode 1
            versionName "1.0"
            testInstrumentationRunner 
        "androidx.test.runner.AndroidJUnitRunner"
        }
        buildTypes {
            release {
                minifyEnabled false
                proguardFiles getDefaultProguardFile('proguard-android.txt'), 
               'proguard-rules.pro'
            }
        }
    
        kotlinOptions { jvmTarget = "1.8" }
    }
    
  3. In your Fragment or Activity, change the import to:

    import androidx.activity.viewModels

  4. The code to create a ViewModel then becomes:

    val viewModel: CalculatorViewModel by viewModels()
    

    instead of

    val viewModel = ViewModelProviders.of(this).get(CalculatorViewModel::class.java)
    

    Use the viewModel object as :

    val viewModel: CalculatorViewModel by viewModels()
    
    viewModel.newNumber.observe(this, Observer<String> { 
        stringResult -> newNumber.setText(stringResult) 
    })
    

    where newNumer is a LiveData object

    In a Fragment that you want to share the Activity's ViewModel, you'd use

    val viewModel: CalculatorViewModel by activityViewModels()
    

That's the equivalent of passing the Activity instance in the (deprecated) ViewModelProviders.of() function.

24
votes

ViewModelProviders.of() has been deprecated. enter image description here

Use ViewModelProvider constructors directly as they now handle the default ViewModelProvider.Factory role.

 mainActivityViewModel = new ViewModelProvider(this).get(MainActivityViewModel.class);
18
votes

Probably you can just use:

val viewModel = ViewModelProvider(this, ViewModelProvider.NewInstanceFactory()).get(MyViewModel::class.java)

without needing to add android.arch.lifecycle:extensions:1.1.1 as the dependency.

14
votes

Actually, what does the ViewModelProviders.of() method do under the hood?

@Deprecated
@NonNull
@MainThread
public static ViewModelProvider of(@NonNull Fragment fragment) {
    return new ViewModelProvider(fragment);
}

It takes Fragment as an argument, creates ViewModelProvider object and passes the fragment directly to ViewModelProvider constructor.

We can use the same way too.

E.g. Before:

OurViewModel mOurViewModel = ViewModelProviders.of(this).get(OurViewModel.class);

After:

OurViewModel mOurViewModel = new ViewModelProvider(this).get(OurViewModel.class);
13
votes

Yes @Tarek, it is deprecated. Use now with AndroidX:

val yourViewModel = ViewModelProvider.NewInstanceFactory().create(YourVideoModel::class.java)
12
votes

Use ViewModelProvider directly instead of user ViewModelProviders.of() as mentioned in the docs.

ViewModelProvider(this).get(XViewModel::class.java)

https://developer.android.com/reference/androidx/lifecycle/ViewModelProviders

10
votes

In case you watch a video from Udacity where you create a GameViewModel and you do not want to write deprecated code just replace:

viewModel = ViewModelProviders.of(this).get(GameViewModel::class.java)

with the following code:

viewModel = ViewModelProvider(this).get(GameViewModel::class.java)
  

and return back to reading ASAP!!

9
votes

I'm using android X and also had this issue.

First of all, you should add these dependencies to your Gradle:

implementation "androidx.lifecycle:lifecycle-extensions:$lifecycle_version"
kapt "androidx.lifecycle:lifecycle-compiler:$lifecycle_version" 

In my case, the $lifecycle_version was 2.2.0-rc02

Second: The import for the ViewModelProvider should be:

import androidx.lifecycle.ViewModelProvider

Than you can initial your vIewModel like the examples below:

val viewModel = ViewModelProvider(this, YourFactoryInstace).get(MainViewModel::class.java)

val viewModel = ViewModelProvider(this).get(MainViewModel::class.java)
6
votes

Use this:

YourViewModel yourViewModel = new ViewModelProvider.AndroidViewModelFactory(getApplication()).create(YourViewModel.class);
5
votes

If you use Kotlin, you can use the property delegate viewModels() like this:

val viewModel: YourViewModel by viewModels()

Source: https://forums.bignerdranch.com/t/solution-to-deprecated-method-viewmodelproviders-of/16833

5
votes

You can use this instead:

viewModel= ViewModelProvider(this).get(YourViewModel::class.java)

"this" in the parentheses is the owner of YourViewModel instance.

3
votes

I'm no expert but i have a line of code that solved my problem in Java. Hope this helps someone.

viewModel = 
new ViewModelProvider
.AndroidViewModelFactory(getApplication())
.create(ViewModel.class);

As i said i would love to provide more details, but this fixed this problem for me.

2
votes

I kept trying and ended up with this solution in Kotlin, you should be able to try it in java too.

MainActivity.kt

 val provider : ViewModelProvider = ViewModelProvider(this)
 val VM = provider.get(ViewModelClass::class.java)

build.gradle

implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:2.3.0"
implementation "androidx.lifecycle:lifecycle-livedata-ktx:2.3.0"

Current version of the lifecycle libraries is 2.3.0 as of 2/2/2021, Refer to https://developer.android.com/jetpack/androidx/releases/lifecycle to check for current version.

2
votes

I'm using factory.

ViewModelProvider.AndroidViewModelFactory
            .getInstance(getApplication())
            .create(DashboardViewModel.class);
2
votes

This answer is for Java but you can understand main point. Solution is that you need use ViewModelProvider because ViewModelProviders deprecated:

//Do not forget import it.
import androidx.lifecycle.AndroidViewModel;

ViewModelProvider.AndroidViewModelFactory(getApplication()).create(YourViewModel.class);

Example usage is:

YourViewModel yourViewModel = new ViewModelProvider.AndroidViewModelFactory(getApplication()).create(YourViewModel.class);

Also, do not forget update Gradle Dependencies: Check here for last versions of them

implementation 'androidx.lifecycle:lifecycle-viewmodel:2.2.0'
annotationProcessor 'androidx.lifecycle:lifecycle-compiler:2.2.0'

!!! However, be careful because some answers recommend this solution but it did not work for me:

yourViewModel = new ViewModelProvider(this).get(YourViewModel.class);

Because when I used this way, I got below Error Message:

Caused by: java.lang.RuntimeException: Cannot create an instance of class com.canerkaseler.mvvmexample.ViewModel

1
votes

When you use dagger then u'll pass factory in constructor

  MobileViewModel mobileViewModel = new ViewModelProvider(this,providerFactory).get(MobileViewModel.class);
0
votes

I was facing the same issue. if anything doesn't work try this piece of code into your oncreate and edit it according to your file and boom you are gtg

val model = ViewModelProvider(viewModelStore,ViewModelProvider.AndroidViewModelFactory.getInstance(application)).get(MainActivityViewModel::class.java)

// you just need to change the model class

-1
votes

Try this...

 LocationViewModel locationViewModel = new ViewModelProvider(this).get(LocationViewModel.class);
-2
votes

If you have this implementation

'implementation 'androidx.lifecycle:lifecycle-extensions:2.2.0'

Try to use viewModel = MainViewModel()

-6
votes

it should work this way

 viewModel = ViewModelProviders.of(this@MainActivity).get(MainActivityViewModel::class.java)