Develop Reference

Android Studio Error running 'app': Default Activity not found

I am using Android Studio 3.4.2 on macOS 10.14.5. Every time I try to run my app, I get the following error:
Error running 'app': Default Activity not found
I tried this solution already (Error: Default Activity Not Found) but it didn't help.
Any help?

If Invalidate Caches/Restart did not help you, then
maybe you forget to declare Your Activity in Manifest
<activity android:name="your.package.YourDefaultActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
Try to add this into your manifest, This lines of code tell the system from which activity Application should start, like an entering point of your app

Make sure you register your default activity
<activity
android:name="org.cocos2dx.cpp.AppActivity"
android:screenOrientation="portrait"
android:configChanges="orientation|keyboardHidden|screenSize"
android:label="#string/app_name"
android:theme="#android:style/Theme.NoTitleBar.Fullscreen"
android:launchMode="singleTask"
android:taskAffinity="" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
Also make sure your selected module & default activity is correct

Error running 'app': Default Activity not found

I do find multiple solutions on here, but non of them work for me...
I cloned an ixisting Androi project, it worked perfectly fine, I added and changed some code, added a fragment and a resource for the fragment. While doing this, everything kept working fine, but suddenly I got this error...
I tried several things:
1. In "Edit Configuration" changed the "Default Activity" to specific activity, but than I get the error that it is not specified in the AndroidManifest.xml (which it is).
2. I tried using the full package path in the manifest ("com.example.something.ActivityLogin" instead of ".ActivityLogin")
<activity android:name=".ActivityLogin"
android:launchMode="singleInstance"
android:screenOrientation="portrait"
android:configChanges="orientation|keyboardHidden"
android:windowSoftInputMode="adjustResize">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
Invalidated caches and restarted
Tried reinstalling Androi Studio
And now for the craziest one:
5. Removed the entire project, pulled the master from git, and the issue is still present!
Also, I did not touch the AndroidManifest nor the ActivityLogin at all, I did not refactor anything...
I'm not sure where to look further, I'm guessing it is an Android Studio (3.2.1 from October 9, 2018) related issue? Also, another project keeps running just fine...

<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.DEFAULT"/>
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
Build-Clean Project or Build-Rebuild Project

Well, I knew it wasn't my code, it was Android Studio...
This did the trick: https://stackoverflow.com/a/52680053/5427848

Could not identify launch Activity: Default Activity not found

I'm new to android and I have encounterded a problem.
The console said that "Could not identify launch activity: Default Activity not found".
I have add
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
in manifests.
And I have tried Invalidate caches/Restart,still not worked.
And the class file which contains the main activity turn green in android studio. I don't know what that means.
This is my manifests file.
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.mrrobot.mycoolweather" >
<uses-permission android:name="android.permission.INTERNET"/>
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme" >
<Activity android:name="com.example.mrrobot.mycoolweather.activity.ChooseAreaActivity"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</Activity>
</application>
</manifest>
The chooseAreaActivity is the one I want to use as launcher activity.

For main activity in your manifest you have to add this with category LAUNCHER (First Activity on launch app):
<activity
android:name=".MainActivity"
android:label="YourAppName"
android:theme="#style/AppTheme.NoActionBar" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
For other activity you have to change category to DEFAULT:
<activity
android:name=".OtherActivity"
android:theme="#style/AppTheme.NoActionBar" >
<intent-filter>
<action android:name="package.OtherActivity" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
Check this Activity and this Start Another Activity
So your code is:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.mrrobot.mycoolweather" >
<uses-permission android:name="android.permission.INTERNET"/>
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme" >
<activity
android:name=".activity.ChooseAreaActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>

Although the question is kind of outdated, I would add the following to all the given answers:
For multi-module projects check carefully that you modify the Manifest corresponding to the Configuration you are trying to run.
Had the same problem and spent 20 minutes just to discover that I was trying to run wrong configuration (with an Application in ModulbeB, while thinking that I was running one from ModuleA).
And sometimes you are working on other module default runnable module changes so you have to change it.

Sometimes it is solved just restarting Android Studio
I had the "Default Activity not found" problem a couple of times and I could solved restarting my android Studio.

If you see that error occur after upgrading your IDEA, upgrading Android Studio version, or Generating a new APK, you may need to refresh the IDE's cache.
File -> Invalidate Caches / Restart...

In your manifest file there was wrong element name (Activity change to activity) declared
<Activity android:name="com.example.mrrobot.mycoolweather.activity.ChooseAreaActivity"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</Activity>
Change it to:
<activity android:name="com.example.mrrobot.mycoolweather.activity.ChooseAreaActivity"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>

When I upgraded Android Studio to 2021.1.1.23 somehow my Run Configuration was switched from app to models, producing this error. Switching back to app resolved the issue for me.

i had these issues with my project:
Default activity not found
xml intellisense was not working
kotlin standard functions were not detecting
All my above issues were resolved by Deleting System cache of Android Studio 3.3 at the home path, and it's working nicely for me,,
Steps:
exit Android Studio
Go to path > C:\Users\YOUR_WINDOW_USER_NAME.AndroidStudio3.3\system
Then you have a \caches folder, delete this caches folder
Now open Android Studio and load your project
Worked for me.. i wasted couple of hours resolving this issue and finally it got resolved in this way.

Exit your android studio IDE. Then locate the "caches" folder in .AndroidStudio3.2 folder.
Location
C:\Users\YOUR_USERNAME\.AndroidStudio3.2\system\caches
For example.
Let's assume say YOUR_USERNAME is called Admin.
C:\Users\Admin\.AndroidStudio3.2\system\caches
Delete the caches folder and start your android studio IDE.

I have tried solutions here and other questions
clean & rebuild & invalidate and restart
make sure that activity has LAUNCHER as category
delete Android cache folder
at End, activity tag was has <activity android:name="com.exmaple.todo.MainActivity" />
when i changed it to <activity android:name=".MainActivity" /> app worked.
I hope it help you if other solution not work.

If your activity is in a different module (e.g. ':library) und you forgot to specify the subproject in the dependencies{} scriptblock of your :app module,
the manifest of :library and therefore the activities it declares, are not imported.
dependencies {
api project (':library')
You may check whether all activities show up in your app-debug.apk by using the following Android Studio menu command:
->Build->Analyze APK->app-debug.apk
Now open the AndroidManifest.xml and check its activity declarations.

I got this error in android 12+ after changing launch activity adding intent-filter but not make it exported.
so not forget.
android:exported="true"

It is likely that the action is not in the manifest.
This is the fix
Attached is an image

My main activity was not declared in Android Manifest File. That's the reason which came that error. This error come because of a declaration problem of Android Manifest file. Please check it. :D

This happened to me aswell took me ages to figure out why, but a weird bug I spotted is that if you run the app with breakpoints in your code without debugging mode it will cause this error to happen.
Quick fix for now: Only use breakpoints for degbugging mode.

Check your duplicate initialize activity in your AndroidManifest.xml
Like bellow:
<activity android:name=".nim.qiaqia.lota.LotaProduct"/>
<activity android:name=".nim.qiaqia.lota.LotaOrderDetail"/>
<activity android:name=".nim.qiaqia.main.activity.RechargeListLotaActivity"/>
<activity android:name=".nim.qiaqia.lota.MiningCoinLota"/>
<activity android:name=".nim.qiaqia.lota.LotaOrderDetail"/>
that can causes ""Default Activity not found" also. So, remove it and see. its works! :)

In my case android manifest was correct. I tried to invalidate Caches and restart but not worked. Then Rebuild project and it also did not work.
Then I realized that last night I added a new library to build Gradle, it was this:
implementation 'com.yalantis:eqwaves:1.0.1' And after removing this everything worked fine.
TIP: "Always have a track of things you do in your project, otherwise you will end up wasting your time"

If you only enabled building the app via app bundle, then this error might also occure when you try installing it as a default APK. Change the deployment option to APK from App Bundle and you are good to go.

No Launcher activity found, The launch will only sync the application package on the device

I got this warning from console when running my application on emulator
No Launcher activity found!
The launch will only sync the application package on the device!
In fact i have declared an activity as the main launcer in AndroidManifest.xml file
<activity
android:name=".myActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
I don't need any other intent-filter to use on that activity.. just basic main and launcher
What's the reason? Please give me a solution..

If the launcher activity is in another package, you will need to specify that as well.
For instance, from one of my personal projects:
<activity
android:name=".activities.MainScreen"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
The MainScreen.java is in the activities package. Also, check spelling for upper or lower case letters.

It seems that you must have "android.intent.action.MAIN" specified immediately before "android.intent.category.LAUNCHER". I encountered the same issue as you when I had the following:
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<action android:name="android.intent.action.SEARCH" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
The issue was resolved only when I re-orderd as follows:
<intent-filter>
<action android:name="android.intent.action.SEARCH" />
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>

In all normal circumstances, listen to what the other guy(s) said.
I was able to replicate your issue using a Mac Book Pro & Eclipse Indigo. when you create your android project, you MUST have Eclipse start you off with a templated activity (like a blank activity). if you don't, and you try to add an activity to your manifest later, Eclipse just derps and can't find the launcher. (i looked at other manifest files and i can't see any differences. i really don't think it's your poor manifest's fault in this special case.)
here's your lazy easy fix:
start a new project, and copy over all the files (make sure you back up ur files first, in case you delete something wrong or mess up the ordering)

Using Eclipse Indigo, open Run Configurations windows, click the project and use launch default activity on Android tab, choose Automatically pick compatible device...and apply.

application not installing on android emulator

I am running tab based application in android.When i try to install the application on the emulator it gives output in the console as
[2011-03-08 12:40:35 - TabBar] Application already deployed. No need to reinstall.
[2011-03-08 12:40:35 - TabBar] \TabBar\bin\TabBar.apk installed on device
[2011-03-08 12:40:35 - TabBar] Done!
Can anyone tell how should i pursue
Thanks in advance
Tushar

I'm also tackled with this same problem and finally I found the solution for it. When you creating a new android project using Eclipes and if you didn't create a activity for your first window, your project's Manifest also don't create proper codings for you to application launch up.
So, you should hardcode them yourself.
First check these codes are available or not in your Project's Manifest file, within your main activity tags.
**
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
**
These two code lines are very important. Because these two lines are calling to android OS to launch this app.
So, Make sure these codes are available in your project's Manifest file. If it's not this below Manifest file code will gets you rough idea to fix this problem.
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.mershanfernando.testingappz"
android:versionCode="1"
android:versionName="1.0">
<uses-sdk android:minSdkVersion="10" />
<application android:icon="#drawable/ic_launcher" android:label="#string/app_name">
<activity android:name=".Main"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>