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When I'm building Gradle with androidx I get the following error. Please help me to solve this issue.

Error Message: Manifest merger failed : Attribute application@appComponentFactory value=(android.support.v4.app.CoreComponentFactory) from [com.android.support:support-compat:28.0.0] AndroidManifest.xml:22:18-91 is also present at [androidx.core:core:1.0.0] AndroidManifest.xml:22:18-86 value=(androidx.core.app.CoreComponentFactory).


<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"


        <activity android:name=".activities.SplashActivity" >
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
        <activity android:name=".activities.LoginActivity" />
        <activity android:name=".activities.RegisterActivity" />
            android:theme="@style/AppTheme.NoActionBar" />
        <activity android:name=".activities.AddBookActivity" />



apply plugin: 'com.android.application'

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

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    implementation 'com.android.support:support-v4:28.0.0'
    implementation 'com.google.android.material:material:1.0.0'
    implementation 'com.jakewharton:butterknife:10.1.0'
    annotationProcessor 'com.jakewharton:butterknife-compiler:10.1.0'
    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'
      • 1
    • Try my solution. Remove all appcompat number verisons from gradle and imports from code, replace them with androidx equivalents and then sync gradle.

After hours of struggling, I solved it by including the following within app/build.gradle:

android {
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8

Put these flags in your gradle.properties


Changes in Manifest:

implementation 'androidx.appcompat:appcompat:1.0.2'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
implementation 'androidx.legacy:legacy-support-v4:1.0.0'
implementation 'com.google.android.material:material:1.1.0-alpha04'

Refer to: https://developer.android.com/jetpack/androidx/migrate

  • 39
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      • 1
    • It worked but after adding these two lines in application tag of manifest i.e. tools:replace="android:appComponentFactory" android:appComponentFactory="androidx"

Reason of this error-

Because after upgrade, androidx.core:core is accessed somewhere, when your project is still not using androidx. So classes like CoreComponentFactory and many others are now found at two places - androidx.core:core and com.android.support:support-compat. That's why this error occured.

What is solution?

You should migrate to AndroidX. If you don't know about AndroidX. Please read What is AndroidX?

How to migrate your project

After Android Studio 3.2 (September 2018), there is direct option to migrate existing project to AndroidX. This refract all packages automatically.

Before you migrate, it is strongly recommended to backup your project.

Existing project

  • Android Studio > Refactor Menu > Migrate to AndroidX...
  • It will analysis and will open Refractor window in bottom. Accept changes to be done.


New project

Put these flags in your gradle.properties


Check @Library mappings for equal AndroidX package.

Check @Official page of Migrate to AndroidX

  • 26
Reply Report

Error explicitly says-

[com.android.support:support-compat:28.0.0] AndroidManifest.xml:22:18-91 is also present at [androidx.core:core:1.0.0]

AndroidX is the latest support library from Google. It contains all previous components from all older appcompat versions. Do NOT use appcompat-v-any number. Instead, use a similar component from AndroidX libraries. Remove the numbered support libraries from your Gradle and your code wherever it is imported. Then sync your gradle.

Component similarity table can be found here. Also, follow the steps mentioned in Migrating to AndroidX.

Again, stop using any previous appcompat numbered versions. There's only AndroidX now.

Hope this helps.

  • 5
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      • 1
    • MD Naseem Ashraf u can clear see in gradle the his project not completely converted to AndroidX so just enough android.enableJetifier=true android.useAndroidX=true
      • 1
    • Remove the numbered support libraries from your Gradle and your code not make sense because the Migrate to AndroidX is complete another process.
      • 1
    • Op has mentioned "...when I building Gradle with androidx " When you use AndroidX one should use all of it otherwise there will be similarity conflicts with components existing in both packages support numbered ones and androidx. That's why I attached the similarity table.
      • 1
    • @code4rox Just because it doesn't make sense to you. You can't downvote an answer. OP's error explicitly says "[com.android.support:support-compat:28.0.0] AndroidManifest.xml:22:18-91 is also present at [androidx.core:core:1.0.0] "

One suggestion to find out the exact reason is to open the manifest file and in bottom you will see a Merge Manifest option where you will see exact reason for failure.

See below image

enter image description here

  • 1
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Project-wide Gradle settings. IDE (e.g. Android Studio) users: Gradle settings configured through the IDE will override any settings specified in this file. For more details on how to configure your build environment visit http://www.gradle.org/docs/current/userguide/build_environment.html

Specifies the JVM arguments used for the daemon process. The setting is particularly useful for tweaking memory settings


When configured, Gradle will run in incubating parallel mode. This option should only be used with decoupled projects. More details, visit http://www.gradle.org/docs/current/userguide/multi_project_builds.html

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