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Cannot resolve symbol 'AppCompatActivity'

I've just tried to use Android Studio. I've created blank project and tried to create Activity which extends AppCompatActivity. Unfortunalty Android Studio "says" that it

Cannot resolve symbol 'AppCompatActivity'

I have compile "com.android.support:appcompat-v7:22.0.+" in dependency list of my "app" module and rebuilt project several times. However I can only use ActionBarActivity. What am I doing wrong?

are you using right build version? is your sdk is up to date?
@Lingviston you're not using the right version. You should use com.android.support:appcompat-v7:22.1.0
Well there wasn't such version that time.
But now there is and it solves the problem :)

A
Akshu Gautam

A little addition to other answers here, for anyone having the same error while using the right lib version and the right class.

When I upgraded to

appcompat-v7:22.1.0

In which ActionBarActivity is deprecated and empty and AppCompatActivty is the way to go, due to some glitch in Android Studio, It didn't quite pick up on version change.

i.e. Even though Gradle ran without errors, the IDE itself kept saying Cannot resolve symbol 'AppCompatActivity' (and it also wasn't available through the Ctrl+N search)

I looked into the .idea/libraries folder and noticed there's no appropriate metafile for the new version of the lib.

So, using the old-reliable File->Invalidate Caches/Restart did the trick. Always try this when you feel something is magically wrong with Android Studio. And then Disable offline mode and sync.


Doesn't work for me either, each time I upgrade the appcompat, I get into lots of problems.
For me this error popped up when updating to Android Studio 2.0 - Clearing the Cache and Restarting as stated above worked perfectly!
I have compile 'com.android.support:appcompat-v7:23.3.0' already in my build.gradle ... but still getting the error
If it didn't work, try this one, worked for me: stackoverflow.com/a/36641765/3758439
same in IntelliJ IDE.
D
DBX12

If the soft methods via gradle file / "Invalidate caches" and the other IDE tools do not work, use the hard way:

Exit Android Studio Navigate in your project to the .idea folder Just Rename the libraries folder Restart Android Studio. It should now recreate the libraries folder and work again.

This worked for me on

Android Studio 3.1.2
Build #AI-173.4720617, built on April 13, 2018
JRE: 1.8.0_152-release-1024-b01 amd64
JVM: OpenJDK 64-Bit Server VM by JetBrains s.r.o
Linux 4.13.0-38-generic

Shahbaz Ali confirmed, it works also on

Android Studio 3.1.3
Build #AI-173.4819257, built on June 4, 2018
JRE: 1.8.0_152-release-1024-b01 amd64
JVM: OpenJDK 64-Bit Server VM by JetBrains s.r.o
Linux 4.13.0-38-generic

moujib confirmed, it works on Android Studio 3.2.1


Ty for the fix! Also, I would like to know if every user here was using the PC version or iOS version of Android Studio. I have some developer friends who never had any of these issues on iOS. I've had tons of issues on PC. Not sure how many times i've tried to clean/rebuild/invalidate cache...
Shahbaz Ali and I used the Linux version, moujib only commented that this solution works in 3.2.1
G
Gabriele Mariotti

Today (22 April) you can use the new AppCompatActivity released with the support libraries v 22.1.0.

Just change your dependency :

compile "com.android.support:appcompat-v7:22.1.0"

Here you can find more info about this new class.


hmm I'm using a higher version but still encounter the issue compile 'com.android.support:appcompat-v7:23.1.1'
C
Community

It is too simple.here are the steps you need to follow

1-Exit Android studio. 2-Go to your project directory. 3-Something like this in my case( F>Android->YourProjectName->.idea). 4)-delete libraries folder present in .idea folder. 5)-restart your android studio. and your issue is resolved.


I would never delete the folder in case something goes terribly wrong. Simply renaming it will suffice. In the worst case scenario, that the libraries folder isn't regenerated, you can go back and restore the "libraries" folder's original name. After everything is known to work, you can then go back and delete the folder you renamed. If your studio is corrupted, it may not regenerate folders - always take caution when deleting files.
This fixed it for me.
After deleting the library folder, come back to android studio. "Do Sync Project with Gradle files"
S
Siddhartha Chikatamalla

I got it fixed by Going to build.gradle file and in dependencies the appcompat one, something like compile 'com.android.support:appcompat-v7:XX.X.X'

Changed it to compile 'com.android.support:appcompat-v7:XX.X.+'

Then click on Sync. All the red squiggly lines should go if everything else in your code is correct.


+1, OMG this worked for me. :) BTW the + sign is for Hey Gradle if any new version of the same release is availible use is for yourself :) . I was using com.android.support:appcompat-v7:25.3.1 now this did a trick: com.android.support:appcompat-v7:25.3.+ Though AS giving me warning: Avoid using + in version numbers; can lead to unpredictable and unrepeatable builds (com.android.support:appcompat-v7:25.3.+)
V
Victor Michael

Check for typos too, i wasted my whole day looking for solutions when i had actually typed AppCompactActivity instead of AppCompatActivity


j
jk7

I got the Cannot resolve symbol error for AppCompatActivity and many other classes & methods after updating Android Studio from 2.2.3 to 2.3, updating Android Gradle plugin to 2.3.0, and updating Gradle to 3.3.

File -> Invalidate Caches / Restart did not resolve the issue.

Preferences -> Build, Execution, Deployment -> Gradle showed Use local gradle distribution selected with Gradle home: /Applications/Android Studio.app/Contents/gradle/gradle-2.14.1 and a warning displayed saying the gradle location was incorrect.

Resolved issue by selecting Use default gradle wrapper (recommended).
Probably just pointing to the new local distribution location would also work.


S
Sathish kumar T.M

Cannot resolve symbol AppCompatActivity Issue.

Do the Simple Step to resolve the problem.

i) Exit the Android studio.

ii) Go to your project directory.

iii) Find the .idea folder in your project directory.

iv) Delete .idea folder.

v) Restart your android studio.

vi) The Issue Will be resolved.


If you go inside the .idea folder and rename the "libraries" folder to something different, the trick works as well. If something goes terribly wrong, you only have to go back and rename the libraries folder back to it's original name and try something else, rather than try to restore the entire .idea folder.
M
Muhammad Etisam Zafar

When you add AndroidX support in Gradle.properties file e.g.

android.useAndroidX=true
android.enableJetifier=true

If you are using Gradle version greater than 3.2, the conventional Appcompat dependancy e.g.

implementation 'com.android.support:appcompat-v7:27.1.1

wont work. Replace this dependancy with:

implementation 'androidx.appcompat:appcompat:1.1.0'

Moreover, change the AppCompatActivity import in your class file from this:

import android.support.v7.app.AppCompatActivity;

to this:

import androidx.appcompat.app.AppCompatActivity;

Done


M
MobileAppDeveloper

Try this. In Android Studio, after putting the dependency in build.gradle. Go to Build --> Clean Project.

It worked for me.


R
Raghav Sharma

Thats really insane, i tried everything, synced with Gradle files, invalidated and restarted android studio. Still the problem persisted. Last resort was deleting .idea/libraries folder and it worked as charm.


S
Sergey Zabelnikov

You can use new AppCompatActivity appcompat-v7:22.1.+ Just add this to your gradle:

compile 'com.android.support:appcompat-v7:22.1.1'


N
Nihas Nizar

For me the issue resolved when i updated the appcompact v7 to latest..

compile 'com.android.support:appcompat-v7:25.3.0'

Hope it helps...:)


S
Seabass77

So my collegue pushed their local.properties which broke everything. I copied my sdk path from another app and did:

File -> Sync Project with Gradle Files

A
AsgharHussain

I was getting this same problem with Android SDK 23, while developing on a Mac OS X Yosemite Machine. It turned out that I did not have Java SDK 7.

Once I installed Java SDK 7 and pointed the SDK from with the Android Studio to the new SDK, everything worked for me.

Here are the steps that I followed:

1) Shutdown Android SDK

2) Install Java SDK for Mac OS X from http://www.oracle.com/technetwork/java/javase/downloads/index.html

3) Start the Android SDK and point the SDK for this project to the new 1.7 Java SDK by going to File -> Project Structure -> JDK Location

4) Restart Android Studio

Hope this help


S
Suragch

Remember to press Alt+Enter or add the import.

import android.support.v7.app.AppCompatActivity; 

Z
Zain

none of below solved my issue

Restart Android

File >> Synch Project with Gradle Files

Build >> Clean Project

Build >> Rebuild Project

File >> Invalidate Caches / Restart

https://i.stack.imgur.com/AZbes.png


m
manojm

I updated my Gradle 2.3.3 to 4.4 and got an error on AppCompatActivity and also Cardview. I tried with clean project and rebuild project. It won't work, then I go to Project Folder -> .idea -> create backup of libraries folder and remove it -> then Rebuild Project that solved my issue.


s
shashank chandak

Lets get going step by step: first clean project by using

Build->Clean

if this doesn't helps then use your second step

File>Invalidate Caches/Restart...

But the real problem begins when all the above options doesn't works so use your ultimate solution is to close project and go to project location directory and delete

.idea

You can open your project now again.


C
Ciske

After upgrading to the latest support library, I had to upgrade to the latest Android studio (beta) version and gradle version before the IDE recognized AppCompatActivity again (invalidating caches and restart did not do the trick)


P
Pang

Add this dependency in project build .gradle.

Follow the example below.

dependencies {

    compile 'com.android.support:appcompat-v7:22.1.0'
}

I use :22.0.0 and cannot find AppCompatActivity class. I have to set it at least to 22.1.0. Thanks.
C
Community

Easist Way

Open app level build.gradle and remove appcompact-v7 dependency & Sync.

Add dependency again & Sync.

Error gone!

Before

https://i.stack.imgur.com/195Yi.png

After

https://i.stack.imgur.com/8cJ3Y.png


Z
Zain

I solved it adding:

import androidx.appcompat.app.AppCompatActivity;

in the "import" zone of the main .java file. It worked for me.

Hope it helps!


N
Nadeem Bhat

You Have to just Do some change in your Gradle App File by adding some dependency

compile "com.android.support:appcompat-v7:XX:YY:ZZ"

while XX:YY:ZZ is the version code that you are using in your gradle file, otherwise if you set this version lower or higher than that you are using , then your app will face some problems like it will crash sometimes


m
mehmoodnisar125

i just update my android studio from 2.3.2 to 3.1.2 version. and this error occurs.

i clean project, rebuild project, invalidate cache/restart but nothing works.

i resolve this error by updating appcompat library from

compile 'com.android.support:appcompat-v7:23.4.0'

to

compile 'com.android.support:appcompat-v7:25.1.1'

in app build.gradle file.


N
Nguyen Minh Hien

If Invalidating caches not helps, just close the project then re-open it. Steps:

File > Close Project

Remove the project out of the starting project list

Close Android Studio

Open Android Studio

Open existed Project with this project


S
SendETHToThisAddress

This happens because of one the following reasons:

You do not have the SDK API installed (this was my problem) Your project/Android Studio doesn’t know where the needed files are Your project references an outdated compile version that does not support AppCompatActivity There is a typo

Possible solutions:

Check your .gradle file to make sure you’re not referencing an outdated version. AppCompatActivity was added in version 25.1.0 and belongs to Maven artifact com.android.support:appcompat-v7:28.0.0-alpha1, so do not use any version earlier than this. In your build.gradle (Module: app) file you should have the dependency listed: dependencies { compile 'com.android.support:appcompat-v7:25.1.0' } You may be using a different version, but just make sure you have listed the dependency. Open the SDK manager and download every API 7 or newer. If you were missing the needed API it will fix that issue, and downloading all the newer API’s can save you some hassle later on as well. Check for typos in your import statement. Make sure it doesn’t say “AppCompactActivity” instead of “AppCompatActivity”. Resync your project (File >Sync project with Gradle files) Rebuild your project (Build >rebuild) Clean your project (Build >clean project) Close and restart Android Studio Update Android Studio Regenerate your libraries folder – In Android Studio, view your files in project view. Find the folder YourProjectName >.idea >libraries. Rename the folder to “libraries_delete_me”. Close and reopen Android Studio. Open your project again and the libraries folder should be regenerated with all of the files; you can now delete the “libraries_delete_me” folder.


S
Srikar Reddy

For me, the issue resolved when I updated the Gradle build version. Don't know why?


D
Däñish Shärmà

https://i.stack.imgur.com/evMQD.jpg


K
Kamal

This can might be in the version difference in the app level gradle check it once and then re-build