启动Activity时出现“错误类型3错误：活动类{}不存在”，错误类型3活动类不存在“

Question

Recently I renamed my android project package name, then when I ran the project it gave these two errors:

Error type 3 Error: Activity class {} does not exist
Error type 3 Activity class does not exist

I checked my build.gradle and found the applicationId didn't change. After updating it, nothing was solved. The same errors kept showing. One appears, then I do something, then the other appears...and so on.

After a lot of searching, they suggested cleaning the project and deleting some folders (like .gradle and build ) and rebuilding the project after restarting Android Studio, but none of that solved my problem.

Any suggestions?

Answer 1

after a long night , I found the solution. simply my phone storage was almost full (400mb) left . I cleaned up some space , and then it worked.

Aditional thing to do if nothing solved in your case : Tools > android > Sync Project with Gradle Files.

Answer 2

yes there is a way click on compact middle pages then right click on pakage name and refactor then rename. hope it will solve your problem. i posted an image, dont know where it gone

Answer 3

It is a easy problem which is happened when you migrate to androidX or refactoring the package name. An easy solution is:

1. Make a new project (same package name as the current one)
2. go to app\\src\\main and delete all files in main directory (for this new project)
3. Go to app\\src\\main and copy all files in main directory (for the old project)
4. Paste the files in app\\src\\main directory (the new project)
5. Run the new project

Answer 4

The problem could be in your Manifest file. Check the AndroidManifest.xml file.

Check the presence of those intent-filters inside your Activity declaration. Like below.

<activity
     android:name=".main.SplashScreenActivity"       
     android:label="@string/app_name"
     android:screenOrientation="portrait">
     <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
     </intent-filter>
 </activity>

If this information is there, maybe some cache problem occurred. Then, try this:

Go to File -> Invalidate Caches / Restart...