Develop Reference

Can't remove Module from Project Structure in Android Studio

I'm trying to remove "library" as a module. I'm using Android Studio 3.0.1.
If I click on the red "-" it removes it but after gradle builds automatically, it adds it back again. I removed the dependency from build.gradle, so it's not used by the "app" anymore. I can't "Delete" the folder from inside Android Studio either. The only thing I can think of is to remove it from Windodows directly, but I'm really curious if it's a bug or why I can't do this from Android Studio.
Any ideas?

As #CommonsWare won't answer the question, I will do it myself.
The solution for the problem is to remove the module name from settings.gradle and after that, deleting the module will work normally.

As #CommonsWare suggested, the solution is to open settings.gradle and delete the unwanted module name.
As #StayCool mentions, you can perform this solution and then restart the IDE (Android Studio) and the unwanted module(s) may reappear.
I got this to work by adding the following steps. It may be overkill, and some steps may do nothing, but here's what worked for me:
While IDE is open with the project:
Open settings.gradle and delete unwanted module names, save &
close file.
Delete .gradle folder and .idea folder. (do not
delete gradle folder--notice the period at start of file name).
In IDE go to File > Invalidate Caches/Restart (answer affirmative to
dialogs).
Your IDE should close and restart, then rebuild the folders you deleted, then the file tree should no longer show the unwanted modules.
If it doesn't work the first time, try the steps again. If it doesn't work a second time, I dunno...

App module disappeared in android studio

I had app module running on my android studio project until I pressed delete by mistake. I am now unable to run my project as it doesn't detect app module.
I can see app folder in project view (containing build, libs, src folders) but I don't see it in android view or configuration setting where it says
I have an old apk file of the project.
I shared my project on github.
Please help me get my module back so that I can run my project.

All I had to do was File->Sync project with gradle files.

In order to not risk and further modify your content, try and clone again your android repo elsewhere and see if your module shows up there.
If it does, copy it back in your current repo.

I had this same issue, twice now. The first time, a full clean/rebuild did the trick. The second time, this didn't work. What did resolve the problem was opening the settings.gradle file and copying everything, then removing it to leave an empty file. Then save and resync Gradle. This failed, but then I pasted the old contents back into the file and did a resync again, which then fixed the issue.
Not sure what the problem was in the first place, but this worked for me so I figured I'd share.

Why does Android Studio don't "accept" "getBoolean"? [duplicate]

I'm importing twitter4j in AndroidStudio, using the following in my build.gradle:
dependencies {
compile 'com.android.support:support-v4:18.0.+'
compile files('libs/twitter4j-core-3.0.4.jar')
}
The project compiles fine, and I can create twitter objects without a problem. However, in Android studio, anything referencing that library shows "cannot resolve symbol" and displays in red. What do I need to do to get Android Studio to recognize the library?
I have already tried rebuilding the project, ./gradlew clean, and closing and re-opening my project.

No idea if this will work or not but my only thought so far: right click the jar file in file tree within AS and select "Add as library..."
EDIT: You can do "File" -> "Invalidate Caches...", and select "Invalidate and Restart" option to fix this.
EDIT 2: This fix should work for all similar incidents and is not a twitter4j specific resolution.

Try changing the order of dependencies in File > Project Structure > (select your project) > Dependencies.
Invalidate Caches didn't work for me, but moving my build from the bottom of the list to the top did.

This is what worked for me.
In the Project panel, right click on the project name, and
select Open Module Settings from the popup menu.
then change the Compile SDK Version to the minimum version available (the minimum sdk version you set in the project).
wait for android studio to load everything.
It will give you some errors, ignore those.
Now go to your java file and android studio will suggest you import
import android.support.v4.app.FragmentActivity;
Import it, then go back to Open Module Settings and change the compile sdk version back to what it was before.
Wait for things to load and voila.

For mine was caused by the imported library project, type something in build.gradle and delete it again and press sync now, the error gone.

I also had this issue with my Android app depending on some of my own Android libraries (using Android Studio 3.0 and 3.1.1).
Whenever I updated a lib and go back to the app, triggering a Gradle Sync, Android Studio was not able to detect the code changes I made to the lib. Compilation worked fine, but Android Studio showed red error lines on some code using the lib.
After investigating, I found that it's because gradle keeps pointing to an old compiled version of my libs.
If you go to yourProject/.idea/libraries/ you'll see a list of xml files that contains the link to the compiled version of your libs. These files starts with Gradle__artifacts_*.xml (where * is the name of your libs).
So in order for Android Studio to take the latest version of your libs, you need to delete these Gradle__artifacts_*.xml files, and Android Studio will regenerate them, pointing to the latest compiled version of your libs.
If you don't want to do that manually every time you click on "Gradle sync" (who would want to do that...), you can add this small gradle task in the build.gradle file of your app.
task deleteArtifacts {
doFirst {
File librariesFolderPath = file(getProjectDir().absolutePath + "/../.idea/libraries/")
File[] files = librariesFolderPath.listFiles({ File file -> file.name.startsWith("Gradle__artifacts_") } as FileFilter)
for (int i = 0; i < files.length; i++) {
files[i].delete()
}
}
}
And in order for your app to always execute this task before doing a gradle sync, you just need to go to the Gradle window, then find the "deleteArtifacts" task under yourApp/Tasks/other/, right click on it and select "Execute Before Sync" (see below).
Now, every time you do a Gradle sync, Android Studio will be forced to use the latest version of your libs.

When i lived to this problem(red color codes but they work correctly) in my project;
As first, i made it that (File -> Indicate Cashes) --> (Invalidate and Restart).
As last, i resync my build.gradle file in my app. After problem was resolved.

Invalidate Caches / Restart didn't work for me this time.
Found a solution like this:
Remove the compile *** or implementation *** line in build.gradle.
Clean and rebuild. Errors should be raised here.
Add the line in step 1 back to build.gradle.
Clean and rebuild.
Weird...

This problem happened for me when my Glass project was not using the SDK installed in Android Studio's default location. I was using another location I had previously from ADT, since I was trying to avoid re-downloading everything. Once I pointed the project back to the SDK location in Android Studio's install location the problem went away.

I had this problem for a couple of days now and finally figured it out!
All other solutions didn't work for me btw.
Solution: I had special characters in my project path!
Just make sure to have none of those and you should be fine or at least one of the other solutions should work for you.
Hope this helps someone!

I had the very same problem recently with Android Studio 1.3. The only working solution was to remove the .gradle and .idea folders and re-import the project into Android Studio.

For those, who tried the accepted answer and have no success,
I tried also the accepted answer and did not work for me. After that, I updated my project with the repository and synchronized the project and the could not resolve warnings are gone.

Invalidate Caches didn't work for me (this time). For me it was enough changing the gradle and syncing again. Or https://stackoverflow.com/a/29565362/2000162

If nothing else helped, you could do as Android Studio suddenly cannot resolve symbols recommends:
Exit Android Studio
Back up your project
Delete all the .iml files and the .idea folder
Relaunch Android Studio and reimport your project

In my case, I had created a new file using the GUI and defined an interface within the file. I kept getting this symbol error because the file was not a "java" file. It had no extension on it at all.
After modifying the file extension to ".java", the system correctly finds the symbols.

In my case the jar file did not have a META-INF/MANIFEST.MF file. After adding one, it worked!

For my case working with AndroidStudio 2.2.3 the solution was to change the gradle wrapper/distribution to use local one in the Gradle Settings (despite of being "recommended").

This worked for me--
(File -> Indicate Cashes) --> (Invalidate and Restart).

I tried Invalidate cache/restart or clean Project -> rebuild project. These didn't work for me.
The final solution was open Project window on the left side of IDE, under Project mode, delete .gradle and .idea folder, THEN you can invalidate caches and restart. This fixed it.

Change compile to implementation in the build.gradle.

Changing the language injection settings worked for me.
Place the cursor on any of the red underlined code and Alt + Enter
Now select Language Injection Settings and a window will open as shown below.
Uncheck the selected option and click Ok
Hope this helps somebody.

It happened to me when I removed the whole files in .gradle/caches, then studio downloaded the dependences. The dependences not showed in the External Libraries but I can build App successfully. rebuild clean Invalidate and Restart have no effect. I solved the problem by the steps:
Close Android Studio completely
Remove .idea package in your project
Restart Android Studio

I have tried this but nothing worked for me:
Invalidate Caches / Restart
Changing the order of dependencies
Sync project with Gradle Files
Clean -> Rebuild Project
In my case, just do:
Delete all files in .idea/libraries folder
Rebuild Project

For me I updated gradle-wrapper.properties into 4.4
distributionUrl=https\://services.gradle.org/distributions/gradle-4.4-all.zip

I found easiest way
Identify the library which is causing syntax error in Studio.
For Example if AppCompatActivity is showing error then you will perform below operation on AppCompat Dependency.
Remove dependency which is showing syntax error & Sync.
Add again & Sync.
That's It, error gone!
Before
After

None of the answers above works for me.
After a lots of attempts, I upgraded com.android.tools.build:gradle in Project/build.gradle from 2.3.0 to 3.0.1, and it works.
I guess the version of the com.android.tools.build:gradle should be match to the version of AndroidStudio, and my AS version is 3.2.1

I tried all of the posted solutions and none of them worked for me. (Though invalidate caches does normally. This time it made no difference). After trying everything posted here the "Error cannot resolve" were still present. And the project did build and run successfully, only the IDE seemed to be confused, not the actual app or device.
My Version of Android Studio is 2021.3.1:
The solution that did finally work for me was updating the "Android Gradle Plugin Version" configuration inside of File -> Project Structure.
It was originally 3.2.1 when it wasn't working. I updated it to 3.5.3 because I have another project that was working fine and it was on that setting.
After making this change and then sync'ing gradle the symbols not resolved error goes away and the IDE once again knows what those classes are.

Closing all files and closing Android Studio works for me.

You need to restart Android Studio.

Android Studio Gradle Already disposed Module

I have installed Android Studio version 1.0.1. I have imported my projects from eclipse and it works fine.
Then I deleted a module and reimported it into my Android Studio project. The gradle build says "BUILD SUCCESSFUL" but it pops up an alert window with the message
Failed to complete Gradle execution.
Cause:
Already disposed: Module: 'MYMODULENAME'
I can't start my app now. Any idea what I can do?
Edit:
I solved the problem with the following instructions:
Switch project view from Android to Project
Remove entry include 'MYMODULENAME' in settings.gradle
The blue box in the module symbol don't show. Then you can delete the module in the context menu
Import the module

Note: this is purely an IDEA/AS issue, gradlew clean | Build > Clean | Build > Rebuild will just waste your time.
Most of the solutions here are blind stabbings in the dark. Here's what I found to be the root cause:
Some of the .iml files may be missing (maybe because we deleted it),
check if the module erroring has .iml.
If it is missing, check if .idea/modules.xml has an entry for that module
While syncing I noticed that IDEA/AS tries to put a new duplicate entry into .idea/modules.xml while there's already one. This duplicate entry is probably disposed of twice while the sync tries to reset the modules in memory.
Quick Solution: In order to make it work the easiest is to delete .idea/modules.xml along with the .iml files. Additionally may worth deleting .idea/modules/ folder if it exists. Restart Android Studio (no need to clear cache) and force a Gradle sync from Gradle view or toolbar to recreate the files.

I figured out this problem by:
./gradlew clean
Restart Android Studio

Simplest solution. (Try this first).
Quit and Restart Android studio. (Quit not close)
Build > Clean your project if needed.

works for me:
File -> Invalidate Caches / Restart... -> Invalidate and Restart

Sometimes gradlew clean or Invalidate Cache and Restart does not help, because these methods do not clean Android Studio specific files by themselves.
In this case, close AS and remove .idea directory and .iml file in a root project where settings.gradle file exists. This will make AS rebuild from the fresh ground.

For me this happened when i deleted a module and built a new one with the same package name
Solution:
Clean & Restart Studio

In the left pane, change to "Project" view.
Delete MYMODULENAME.iml

For an alternative solution, check if you added your app to settings.gradle successfully
include ':app'

For me this happened when I removed a module and tried to build the project:
Simple solution was to Invalidate the cache & Restart.
Android Studio>File>Invalidate Caches>Invalidate & Restart

Had a similar issue when working with RN components in my Android project and the only way to get around this issue was to ignore the gradle project.
To do this:
Click on the gradle tab on the right hand side of AS
Right click the gradle module which is causing an issue
Click "Ignore Gradle Project"
Perform a gradle sync which should be successful now
If you need this module perform the 4 above steps again, this time when right click on the gradle project it'll show "Unignore Gradle Project"
Gradle sync should now work
No idea what causes this but I've had this happen to me when using React Native Maps.
Note: If you're still having issues following this. Try to refresh the gradle project which was causing issues.

If gradle clean and/or Build -> Clean Project didn't help try to re-open the project:
Close the project
Click "Open an existing Android Studio project" on the "Welcome to Android Studio" screen
Select gradle file to open
Warning Be aware it's a destructive operation - you're going to loose the project bookmarks, breakpoints and shelves

below solution works for me
Delete all .iml files
Rebuild project

For Solve this issue take it this simple steps.
Find the .idea folder in your Android studio under the Folder Project.
In .idea --> Find this one. .idea/.modules
Simple Delete that .modules folder and restart Your studio.
when it reopens gradle sync Automatically and also recreate .modules folder and files.
Error has gone !

I also face this problem sometimes. Click on gradle console in bottom bar of android studio, at right side. It will show the exact error in logs. My problem was that I had compile SDK 22 and imported appcomact library was of sdk 23.

I had the same problem,
after delete some gradle files (of aws)
i solved it by mark them "ignore gradle"
I believe it is not the best answer but it solve it for me
Gradle (at the right bar)--> right click on the problematic gradle --> ignore

Although the accepted answer didn't work for me (unfortunately I can't leave a comment), it led me in the right direction.
in .idea/libraries i found that there were some duplicate xml files (the duplicates were named with a 2 before the _aar.xml bit).
deleting those, restarting android studio and sync fixed the error

I was having this issue because gradle and Android Studio were using a different path for the jvm. In the Event Log there was an option for AS and gradle to use the same path. Selecting this and then doing an invalidate cache & restart resolved the issue for me.

In my case, same as in this question, it happened because I had my project in a symbolic link directory. After reopening the project in the real directory and reconfiguring gradle (File -> Sync with Gradle files) the problem went away. Shame on you, Android Studio!

What is Android Dependencies? Remove it from Build Path, ClassNotFoundException occurs

I'm working on a team project. I included a .jar file in Build Path and committed to SVN. When I updated code in my working directory, a new folder appears in Eclipse called "Android Dependencies". If I let it be there, my program runs; If I remove it, my program reports a ClassNotFoundException.
Now how to fix this ClassNotFoundException?

For the people whose heart dropped when they read the comment that deleting the Android Dependencies virtual folder will destroy your project, there is an easy fix.
Right click on the destroyed project
Select "Android Tools > Fix Project Properties" in the dropdown
I hosed my project dependencies when trying to set up my git repo, and this is fixed it.

Android Dependencies is a virtual folder where Eclipse shows what JAR files the project depends on. It's not a physical folder; you won't find it on your hard disk. And the folder is not checked in into Subversion.
Do not delete that folder. You will destroy your project.
To fix it, just revert to an older Subversion revision and check it in again.

I've had a similar problem after setting up a git repo with my project.
The problem was that the appcompat import lost its folder reference.
If the 'Fix Project Properties' mentioned doesn't work for you try this:
Go to Project > Properties
Go to the 'Android' tab
Under 'Libraries', if there's a red 'X' next to the appcompat folder, remove
it then hit 'add' and add it in again. The reference should show a
green tick now.
Save and clean the project if needs be

If you also have marked project build target below API level 16 in the Android project properties, the error is going to come because prior to this level, there was no Android dependencies.