Develop Reference

API 'BaseVariant.getApplicationIdTextResource' is obsolete and has been replaced with 'VariantProperties.applicationId'

When building gradle I'm getting this message:
API 'BaseVariant.getApplicationIdTextResource' is obsolete and has been replaced with 'VariantProperties.applicationId'
I'm using Android Studio 4.1 Canary 10 and gradle:4.1.0-alpha10

It seems like the Navigation Safe Args plugin uses getApplicationIdTextResource(), so it is most likely that the error message is caused by your usage of that plugin.
You'd want to star the existing issue to ask the Safe Args plugin to use the new replacement API.

Changing to androidx.navigation:navigation-*:2.4.0-alpha02 as described here allowed a build of my app under Arctic Fox without getting the getApplicationIdTestResource warning
From the application build.gradle file:
def nav_version = "2.4.0-alpha02"
classpath "androidx.navigation:navigation-safe-args-gradle-plugin:$nav_version"
And in the build.gradle file:
def nav_version = "2.4.0-alpha02"
implementation "androidx.navigation:navigation-fragment:$nav_version"
implementation "androidx.navigation:navigation-ui:$nav_version"
androidTestImplementation "androidx.navigation:navigation-testing:$nav_version"

few days i see the same issue. Then i go to ->
build.gradle file
My Dependencies before update
check the dependencies
I update the dependencies google services to 4.3.4
dependencies {
classpath 'com.android.tools.build:gradle:4.1.1'
classpath 'com.google.gms:google-services:4.3.4'
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
After update
Now its working fine.

This error was for NavigationComponent for me in Android Studio Cannery 13.
So I changed the nav_version to this and My issue was solved.
ext {
*************** nav_version = "2.4.0-alpha10" ************
}
dependencies {
classpath 'com.android.tools.build:gradle:7.1.0-alpha13'
classpath "androidx.navigation:navigation-safe-args-gradle-plugin:$nav_version"
and in app module build.gradle:
implementation "androidx.navigation:navigation-fragment:$nav_version"
implementation "androidx.navigation:navigation-ui:$nav_version"
androidTestImplementation "androidx.navigation:navigation-testing:$nav_version"

It will be solved, when 4.2.0 is stable.
From the existing issue:
Android Gradle Plugin deprecated the getApplicationIdTextResource()
API on the class BaseVariant in version 4.1.0 (see bug). The
replacement API (onVariantProperties) did not work properly for
feature libraries, so to avoid the deprecation warning, reflection was
used. That is only a short term solution, and when AGP 4.2.0 is stable
we should update to that version and remove the reflection immediately
So if you need Safe Args and do not need latest features of Gradle, keep Gradle version in Android Gradle Plugin version at 3.6.4. Once stable 4.2.0 released, update to the latest.

This error happened after i updated kotlin version to 1.7.
this was for NavigationComponent in Android Studio
So I changed the nav_version to this and My issue was solved : "2.4.0-beta02"
// Navigation Component
implementation "androidx.navigation:navigation-fragment-ktx:2.4.0-beta02"
implementation "androidx.navigation:navigation-ui-ktx:2.4.0-beta02"

For me it was because of different Kotlin versions between IDE Kotlin plugin and project_name/build.gradle file
classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.3.72"
"Kotlin version that is used for building with Gradle (1.3.72) differs from the one bundled into the IDE plugin (1.4.31) "
Once I made it even it started to compile again.

In my case I was using 2.3.1 version of navigation-fragment.
I just updated it to 2.4.2 and it's helped me

So, What i have done is that I have upgraded all the gradle plugins as well as dependecies versions and then run, It worked for me

I had the same problem and it was solved like this:
So I go to -> build.gradle file
My dependencies before upgrade
check the dependencies
I update Google services dependencies to latest version
dependencies {
classpath 'com.android.tools.build:gradle:(latest version)'
classpath 'com.google.gms:google-services:(latest version)'
}

Android Studio 4.1 giving the following information and It will be removed in version 5.0 of Android Gradle Plugin.
API 'BaseVariant.getApplicationIdTextResource' is obsolete and has been replaced with 'VariantProperties.applicationId'.
It will be removed in version 5.0 of the Android Gradle plugin.
For more information, see TBD.
To determine what is calling BaseVariant.getApplicationIdTextResource, use -Pandroid.debug.obsoleteApi=true on the command line to display more information.

As #ianhanniballake has pointed out, it seems likely that it's caused by the Navigation Safe Args plugin, see the existing issue, also referenced from his answer. The issue was marked as fixed on 9 November.
In terms of fixing the build error, upgrading Android Studio from 4.1.0 to 4.1.1 fixed it for me.

delete the .idea and .gradle files from the project .. it worked with me

Android studio missing classes (Constraint Layout) (has been resolved)

Android studio missing classes.
The layout is blank.
Main.Activity is red letters.
[Soultion in the answer area]

implementation 'com.android.support.constraint:constraint-layout:1.1.3'
add this line under dependencies in your build.gradle file

If Android Studio is not identifying the project as Gradle based, it means you imported the project source code from wrong directory. Try to reimport the project from a directory where you have see build.gradle file.

Follow these steps Add ConstraintLayout to your project
Or if you are using AndroidX
You need to use different build artifacts
implementation 'androidx.constraintlayout:constraintlayout:1.1.2'
Refer here for AndroidX Migrating to AndroidX

My Solution:
First,I delete Android Studio,and then Download Android Studio(include emulator and SDK) again.
Second,I change the name of my homework.
Third,I choose "Open an existing Android project".
Forth, Gradle Scripts->build.gradle->
dependencies {
classpath 'com.android.tools.build:gradle:3.3.2'
}
replace
dependencies {
classpath 'com.android.tools.build:gradle:3.2.1'
}
Done.

Getting "package android.support.multidex does not exist" after upgrading to Android Studio 2.3

I updated from Android Studio 2.2.3 to Android Studio 2.3 yesterday, and I ran into the following two problems:
Upon updating, Gradle 3.2 was installed by default, but syncing my
project would not work and I kept getting an error saying "Gradle 3.3
is required". Using the default Gradle wrapper doesn't work. The only way to fix this was to download Gradle 3.3
manually and point to the directory in build settings.
On running my project, I kept getting a string of errors involving my
BaseApplication class which extends MultiDexApplication. The
error goes something like this:
Error:(19, 62) error: package android.support.multidex does not exist
I am unable to resolve this error. I have buildToolsVersion '25.0.2', and my project compiled and ran properly before upgrading to Android Studio 2.3. Can anyone help me with this problem?

I have passed the building. my solution is that adding explicit dependencies in build.gradle.
compile 'com.android.support:multidex:1.0.1'

The solution to this problem is to add the following:
dependencies {
implementation 'com.android.support:multidex:1.0.3'
}
in your build.gradle file.
This was not required prior to Gradle 3.3. This problem occurs only for apps that support Android versions below Lollipop (API level 21).
References:
1. Multidex support prior to Android 5.0.

Replace import android.support.multidex.MultiDexApplication; with
import androidx.multidex.MultiDexApplication;

what works for me is adding to your (app) build.gradle
dependencies {
implementation 'androidx.multidex:multidex:2.0.1'
}

In addition to:
dependencies {
...
implementation 'com.android.support:multidex:1.0.3'
}
It is necessary to add this:
defaultConfig {
...
multiDexEnabled true
}

Gradle Sync failed could not find constraint-layout:1.0.0-alpha2

Problem :
Error:Could not find com.android.support.constraint:constraint-layout:1.0.0-alpha2.
Required by:
myapp:app:unspecified
Background :
Android Studio 2.2 P 1

Support libraries for ConstraintLayout could not be installed/updated.
Just open Preferences > Appearance & Behavior > System Settings > Android and move to SDK Tools tab. Check the following fields and install.

In my case, that support libraries for ConstraintLayout were installed, but I was adding the incorrect version of ConstraintLayout Library in my build.gradle file. In order to see what version have you installed, go to Preferences > Appearance & Behavior > System Settings > Android SDK. Now, click on SDK Tools tab in right pane. Check Show Package Details and take note of the version.
Finally you can add the correct version in the build.gradle file
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
compile 'com.android.support.constraint:constraint-layout:1.0.0-alpha9'
testCompile 'junit:junit:4.12'
}

The fix is to update the android gradle plugin in your build.gradle.
This should work:
classpath 'com.android.tools.build:gradle:2.2.0-alpha2'
Or you can use the latest:
classpath 'com.android.tools.build:gradle:2.2.0-alpha3'

My problem was, that the SDK Tools updated it to the latest version, in my case it was 1.0.0-alpha9, but in my gradle dependency was set to
compile 'com.android.support.constraint:constraint-layout:1.0.0-alpha8'
So, you can change your gradle build file to
compile 'com.android.support.constraint:constraint-layout:1.0.0-alpha9'
Or you check "Show package details" in the SDK Tools Editor and install your needed version. See screenshow below. Image of SDK Tools

Ensure you have the maven.google.com repository declared in your module-level build.gradle file
repositories {
maven {
url 'https://maven.google.com'
}
}
2.Add the library as a dependency in the same build.gradle file:
dependencies {
compile 'com.android.support.constraint:constraint-layout:1.0.2'
}

I updated my android gradle plugin to 2.2.0-alpha4 and constraint layout dependency to 1.0.0-alpha3 and it seems to be working now

First I tried everything that I have read on stackoverflow...from updating gradle to XY version, to updating ConstraintLayout to XY version...I even update my SDK tools and Android Studio to the latest version...but nothing was working.
The only solution that worked for me was that I delete ConstraintLayout library from gradle and SDK, then I opened random xml layout and in Design view under Palette section search for ConstraintLayout. If you have successfully deleted library from your project then you will be able to install the library from there if you double clicked on ConstraintLayout element.
That has create next line in my app build.gradle:
'com.android.support.constraint:constraint-layout:1.0.0-beta1'
In my project build.gradle I have this:
classpath 'com.android.tools.build:gradle:2.2.2'
Android studio version 2.2.2

Alpha version is no longer available !
implementation 'com.android.support.constraint:constraint-layout:1.1.3'

Just to make sure that in studio version 2.3 you won't see a dropdown near constraint-layout in sdk tools, it will by default install the latest version
To get the desired version check the box saying show package details and boom you can now choose the desired version you want to install

gradle com.android.tools.build:gradle:2.2.0-alpha6
constraint layout dependency com.android.support.constraint:constraint-layout:1.0.0-alpha4
works for me

For me it was a completely different issue. When I installed constraint dependancy in SDK tools, the tools somehow wrote them into the wrong directory. That is
/home/${USER}/Android/Sdk/extras/+m2repository+/com/.../constraint
instead of
/home/${USER}/Android/Sdk/extras/+android+/+m2repository+/com/.../constraint
Remedy:
Just copy the 1.0.0-alpha* directories into the latter path

While updating SDK tools, a dilog box presented with Constraint layout version that is going to get installed. Note that and update your dependency based on that. In my case it was installing beta3.
I changed my dependency like below. After that it worked.
compile 'com.android.support.constraint:constraint-layout:1.0.0-beta3'

In my case, I had to remove the previous versions first and download the latest one instead. v1.0 stable was released on Feb 23rd.

In my case, I had a multi-module project called "app" and "sdk". The "sdk" module is the one where I had added the constraint layout library. I got the error when I tried to incorporate "sdk" into a new multi-module project called "app2". The solution was to ensure I had added the Google Maven Repository to the project-level build.gradle file for "app2". The Google Maven Repository can be added by putting "google()" under allprojects.repositories in the project-level build.gradle file:
allprojects {
repositories {
jcenter()
google()
}
}

In my case, I was using AS 2.3 and I wanted to use the currently latest ConstraintLayout 1.1.3, but the latest version in my Preferences > Appearance & Behavior > System Settings > Android was 1.0.2.
To use ConstraintLayout 1.1.3, I updated my AS from 2.3 to currently latest 3.2.1, com.android.tools.build:gradle from 2.2.2 to 3.2.1, gradle from 3.3 to 4.6 and buildToolsVersion from 25.0.0 to 28.0.3.
I also added maven { url 'https://maven.google.com' } to the Maven repositories in the project-level build.gradle file and that solved my problem.

Just as a heads up to those still searching for this.
ConstraintLayout 1.0.1 and lower have been deprecated by maven.
For a list of available constraint layouts that can be downloaded, see below:
https://maven.google.com/web/index.html?q=Constrain#com.android.support.constraint:constraint-layout
The easiest solution at the moment, is to change
implementation 'com.android.support.constraint:constraint-layout:1.0.0-beta1'
to
implementation 'com.android.support.constraint:constraint-layout:1.0.2'

I used com.android.support.constraint:constraint-layout:1.0.0-alpha2 with classpath 'com.android.tools.build:gradle:2.1.0', it worked like charm.

Not sure if I'm too late, but in case someone has still the error after an update of ConstraintLayout and Solver over the SDK Tools, maybe this solution could help: Error:(30, 13) Failed to resolve: com.android.support.constraint:constraint-layout:1.0.0-alpha4

Its available in androidx as following package
implementation "androidx.constraintlayout:constraintlayout:2.0.0-alpha1"

Update your constraint layout dependency to the relevant version from '1.0.0-alpha2'. In my case, I changed to the following.
compile 'com.android.support.constraint:constraint-layout:2.0.0-alpha5'

I added the following script in build.gradle(app) under android & I was able to compile.
compileOptions {
sourceCompatibility 1.8
targetCompatibility 1.8
}

Similar issue solved by Reinstalling Android Studio.

i'm try constraint layout dependency update available 1,and plugin gradle alpha-6,it worked

Gradle syncs with ButterKnife

I added ButterKnife to my android project. Like the documentation says, i added this dependencies to the build.gradle:
dependencies {
...
compile 'com.jakewharton:butterknife:8.0.1'
apt 'com.jakewharton:butterknife-compiler:8.0.1'
}
And i'm getting this error when gradle syncs:
Error:Could not download rxjava.jar (io.reactivex:rxjava:1.1.3): No cached version available for offline mode
Do you know how to fix this?
Thanks.

You should Turn Off the offline gradle build in android studio's gradle settings.
Then it will take the updated library from repo.