Android Studio inline compiler showing red errors, but compilation with gradle works fine

I've set up my project in Android Studio to use the Square Wire library, as per this question.

Build -> Compile Project works fine.

2:03:10 PM Compilation completed successfully in 31 sec

However, if I open one of my generated Protocol Buffer files, then the Square package is not being recognized.

Another symptom is that methods inherited from the Square Message class are showing as "Cannot resolve method" compile errors in the editor, even though they build and run fine.

Do I need to do something more than just adding the dependency in build.gradle for my module in my project?

The following steps helps

1. Close your project, and in your project folder delete project/.idea
2. Delete ~/.gradle folder.

Open the project again. Everything should be solved.

Thanks to free3dom for getting me on the right track here.

Diagnosis

The Sync Project with Gradle Files option in Android Studio seems to keep the Project Structure libraries up to date.

However, in my case there were some errors:

Expanding the (not very obvious) link showed the detail. My wire-runtime library was showing in an incorrect location:

This seemed to be a hangover from my original configuration where I had imported the JAR into a libs folder.

dependencies {
    compile fileTree(dir: 'libs', include: '*.jar')
}

I subsequently changed it to be imported directly from Maven Central (as per here), and it seems that the old setting was never overwritten with the new one.

The Fix

The fix is to delete the library dependency from the Project Structure screen and then Sync Project with Gradle Files again.

More Detail

You can also see what path is being used to the resource by opening the .idea/libraries/wire_runtime_1_2_0.xml directly.

My broken one was:

  <component name="libraryTable">
  <library name="wire-runtime-1.2.0">
    <CLASSES>
      <root url="jar://$PROJECT_DIR$/MY_MODULE/libs/wire-runtime-1.2.0.jar!/" />
    </CLASSES>
    <JAVADOC />
    <SOURCES />

After deleting and re-adding the library it changed the root url to:

      <root url="jar://$USER_HOME$/.gradle/caches/artifacts-26/filestore/com.squareup.wire/wire-runtime/1.2.0/jar/44e7acbd5eb6f29698181dc3d67a60acf7efee80/wire-runtime-1.2.0.jar!/" />

Update

Android Studio v0.4.4 apparently fixes other bugs which have the same symptoms, so if you have an older version you may wish to upgrade.

Simple Solution

Go through the link and it worked for me.

1. Choose File option from menu on left top side of android studio.
2. Select the option: Invalidate Cache/Restart It will open an dialog.
3. Click on the first button with option: Invalidate and Restart
4. It will close Android Studio and restart it. Also, it will start re-indexing the project.

It resolved my problem

> Go to File > Invalidate Cache/Restart > Invalidate and Restart

Source here for youtube

1) Click on the gradle icon (right side on the android studio)

2) Click on the refresh button and wait for the issue to be resolved :D

For me

> deleting .gradle and .idea folder

of project solved the problem.

I was still having the same problem with Android Studio v3.2.1 constantly, and sorted out the problem just removing these two sub-folders of the .idea folder (no need to delete the whole .idea folder) while a gradle sync didn't work:

• ./idea/caches
• ./idea/libraries

Just do this on your Android studio:

> File -> Invalidate caches/Restart -> Invalidate and Restart

This worked for me. No need to clear ./gradle or ./idea folder

My hacky fix for this -

1. Open your build.gradle file
2. Cut out everything inside dependencies{}
3. Paste in notepad for super safe temporary keeping
4. Choose 'Sync Now' in the build.gradle file
5. Wait for Sync to fail
6. Paste your dependencies back in
7. 'Sync Now' again

Tried a lot of solutions and this was the only fix for me.

I had this problem after upgrading to Android Studio 3.1. I solved the issue by upgrading all the components I use. So I changed the following entries in my build.gradle (app):

1. Upgrade SDK (from "compileSdkVersion 25" to "compileSdkVersion 26" or maybe higher when you read this note):

//compileSdkVersion 25

compileSdkVersion 26

Comment: This change forced program to download/install new sdk during next sync.

2. Upgrade appcompat-v7:

//implementation 'com.android.support:appcompat-v7:25.4.0'

implementation 'com.android.support:appcompat-v7:26.1.0'

3. Upgrade firebase:

//implementation 'com.google.firebase:firebase-ads:11.4.2'

implementation 'com.google.firebase:firebase-core:12.0.1'

implementation 'com.google.firebase:firebase-ads:12.0.1'

4. In PROJECT build.gradle, upgrade google-services:

//classpath 'com.google.gms:google-services:3.1.0'

classpath 'com.google.gms:google-services:3.2.0'

5. Upgrade gradle (from 4.4 to 4.6). From gradle-wrapper.properties: distributionUrl=https://services.gradle.org/distributions/gradle-4.6-all.zip

After these changes, clean project, invalidate cache/restart, remove .idea/libraries content and resync (not sure about the order but ALL these activities solved the issue for me).

Deleting libraries folder in .idea solved the issue for me. It is located in project's root/.idea/libraries.

I'm using Android Studio 3.1.4

I am fixed by below method

Method 1

> File > Invalidate Cache/Restart > Invalidate and Restart

Method 2

• If you are facing this error only for particular project, Then do this

> 1. Close current project > 2. Go to your project path C://User/Android studio project/your project > 3. Delete two files .gradle and .idea

• If you are facing this error for all projects, Then do this

> 1. Close Android studio > 2. Go to the file C://Users/your username/ > 3. Delete files .gradle , .cache ,.android, .AndroidStudio3.5

if File -> Invalidate caches/Restart -> Invalidate and Restart is Not Working then follow few step.

1.) Close Your Android Studio

2.) Then Delete Manual on C:\Users\Balbir\ .AndroidStudio4.0\system\caches Folder.

3.) Start Android Studio

It is Work For Me.

Below steps when the Project is succesfully compiled but with unresolved classes (All classes usage will be in red color in all files)

Step 1. Delete .gradle file

Step 2. Delete .idea file

Step 3. Open new Android studio Window with some other android project on your system and close your Project with error

Step 3 . Now Open/Import the Project once again from the studio toolbar Android Studio ->File -> Open

Note: Now when you import the project the new .gradle and new .idea folders will be autogenerated with resolved dependencies by the compiler.

If all above answers don't work for you. Just try update your dependencies to latest version. It worked for me.

In my case, for some reason, Android Plugin Version wasn't set. I did try clearing cache and removing .gradle and .idea as well, but it didn't work out and after finally wandering for hours, I found this.

I tried most of the fixes above and what actually worked was deleting all the .AndroidStudio config folders and then restarting Android Studio.

• Location: C:\Users\your.username

I found easy way

• Open app level build.gradle
• Remove dependency which is showing error & Sync.
• Again add dependency & Sync.

Error Gone!

Before

After

Deleting the .idea/caches and .idea/libraries should sort out all the errors.

It seems that everyone uses a different approach for getting around these issues. I'll suggest another one that I feel is a bit less invasive than the others. When I introduce changes from an aar library that I include, I will open up the "settings.gradle" file for the project.

Then cut out the main project module from the list of projects:

include ':mainproj',

and then sync your project. Then paste it back in and re-sync your project once more. I believe that this is the same as some of the manual deletion steps, but this lets you do so from the IDE a bit quicker and less painfully.

These solutions didn't help me with the same problem in Android Studio 0.5.8.

I described my answer to the same question (I guess): https://stackoverflow.com/a/23891829/534698 I just deleted ~/.AndroidStudioPreview directory (in Ubuntu). I missed all my Android Studio settings but it works.

Encountered the same issue where there's a squiggly lines under one of my modules. Turns out its coming from one of the java files from the generated folder. What I did was to exit Android Studio, delete .idea and .gradle directories, and NEVER open that generated folders again otherwise the red lines will come back.

Android Studio 4.2 in 2021 appears to still sometimes have this issue.

As a quick first attempt fix before you try the more involved ones here: exit and then restart Android Studio (i.e. the traditional, turn it off an on...) . This fixed it for me.

If that does not work, then its time to work through the more involved answers here...

I had a similar issue before, invalidating cache and restarting didn't resolve it. I just did a Gradle Sync and everything worked fine.

Solved the issue by cleaning project Build->Clean Project

For me, I refer a jar in a module library. It cannot resolve the symbol in the jar. So I find the solution for my situation. Use the provided way.

provided fileTree(include: ['xxx.jar'], dir: '../moduleX/libs')

All the answers above didn't work for me. My problem was that i had 3 modules, with 2 of them with the same package name.

It was ok for android studio <= 3.2.1.

For android studio > 3.2.1, ressouce was red.

I solved it like this mention here (i just made differents packages name for each modules ) : https://stackoverflow.com/questions/57623617/any-android-studio-version-3-2-1-show-red-resource-but-still-compile

I got the same issue cleared using the following steps:

1. update the library version in gradle to any random number, eg: lib_1.0.0 -> lib_1.0.0.0

2. gradle sync

3. sync shows error

4. revert the version change lib_1.0.0.0 -> lib_1.0.0

5. gradle sync

Open the java file with imports to see the error cleared.

None of the solutions worked for me..I resorted to uninstall java from my computer, running android studio to make sure it detected the uninstall and then installing it again.

If you choose to go this way try changing the jdk path and setting the new path in the project structure. If that doesn't work, go ahead and uninstall java.

I have only make a Clean Project and Rebuild Project before restarting Android Studio, it solves my problem. Maybe Android Studio actually do not update references in the interface

I know it's an old question but maybe this will help someone as none of the answers above worked for me, except for this answer from Victor Choy that inspired the fix for my situation so I have to thank Victor for the answer.

after updating to android studio chipmunk using AGP version 7.2.0 and wrapper version 7.3.3 I encountered an issue with one of my module libraries that was basically a jar file. my editor showed errors just like the errors in the question but my app compiled fine and ran without an issue. so the problem was I had the library dependency in my build.gradle file as follows:

dependencies{
   ... //other dependencies
   api project(':foo-library')
   ...
}

but after I saw Victor's answer I changed it to this:

api fileTree(include:['foo-library.jar'], dir: '../foo-library')

and it resolved the errors that was caused by usage of this library in my code. I don't know why it happened because before updating android studio everything was ok.

you can replace api with implementation or any other dependency prefix that suits your needs.

The following worked for me.

In the build.gradle file, add the below line:

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