Develop Reference

MainActivity NoClassDefFoundError

I seem to be having a similar problem to a myriad of the community; however, I don't seem to have the same symptoms (or at the very least, my Google-fu is not allowing me to find it).
Long story short: The app is giving me java.lang.RuntimeException: Unable to instantiate activity.
From what I understand this can only be caused by improper order of loading libraries or by missing the file in the AndroidManifest.xml.
Here is my AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="net.alexanderlyons.livingpokedex">
<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=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
Here is a link to my repository for those wanting to build it themselves. If anyone can give me insight as to what might be wrong.
Note: This may be due to my .gitignore, as the last time I built, it was on my main tower. I am only running into this issue on a remote machine.
TL:DR - My MainActivity is not loading, it exists in the AndriodManifest.xml, and I am only using gradles to load files, not local jars.

Your problem can be caused by different things, but the most common of it is you having too many libraries loaded, with too many methods.
You should enable multidex in your app, here's the guide:
multidex
A quick tutorial:
Add "multiDexEnabled true" to your gradle config (under target sdk version, for example).
Add this to your dependencies:
dependencies {
compile 'com.android.support:multidex:1.0.0'
}
And make sure you application extends this:
<application
...
android:name="android.support.multidex.MultiDexApplication">
...
</application>
Either via code or via manifest.
Edit:
Test the project with the build tools 22, sd version 22 and target 22. Also, use the support libraries 22.+

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.

Android Studio Development - Even the default app won't work -

I have decided to try to learn some Android App Development however I am unable to follow even the most basic tutorial. My problem is that what ever I seem to do, the compiler complains about about the Manifest.
Failure [INSTALL_PARSE_FAILED_MANIFEST_MALFORMED]
However, this happens when the project is completely unchanged from when Android Studio created it.
The Manifest is below which is also unchanged but is copied below any way.
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="Toby.projecttoolkit" >
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".Home"
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>
Can somebody shed some light on why this might be happening? Any help in this area would be really appreciated.
Many thanks
Toby

I had a similar issue, and I resolved it by changing the package name to begin with a lowercas later i.e use toby.projecttoolkit instead of Toby.projecttoolkit.
Apart from that the Manifest file looks fine.
Refactor the package, clean, refresh and build the project. Make sure your project as no errors and try to run it.

Android SDK Manifest file error: INSTALL_PARSE_FAILED_MANIFEST_MALFORMED

I'm a beginner when it comes to both Java and android SDK, and I had some issues that I dealt with to finally be able to run my app, and than I get this error and I just can't figure it out.
So this is the Console:
[2013-09-17 19:59:23 - AndroidFlow] Installation error:INSTALL_PARSE_FAILED_MANIFEST_MALFORMED
[2013-09-17 19:59:23 - AndroidFlow] Please check logcat output for more details.
[2013-09-17 19:59:23 - AndroidFlow] Launch canceled!
(Sorry for text fragmentation, it doesn't fit in the same line)
And heres the logcat snap:
Also, heres the Manifest file:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.domiq.androidapp"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="16"
android:targetSdkVersion="18" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<service android:enabled="true"
android:exported="false"
android:isolatedProcess="false"
android:label="flow service"
android:name="com.domiq.androidapp.appservice"
android:permission="string"
android:process="string" >
</service>
<activity
android:name="com.domiq.androidappp"
android:label="androidapp" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
Any suggestions? I've tried a lot of stuff (as you can see nothing is in capital letters etc...)

In the future, copy the text out of LogCat (select the lines, press <Ctrl>-<C> to copy) rather than use screenshots.
That being said, here are some obvious problems:
Your android:name in the <activity> is invalid, as it does not have the name of your Activity class.
The one that is causing your error is the android:process attribute in the <service> element, which is malformed and unnecessary.
I am skeptical that the android:name in your <service> points to a Service implementation class.
I strongly encourage you to get rid of android:isolatedProcess and android:permission, as what you have will probably not work the way you expect.

Are you sure your Activity's name is com.domiq.androidappp. This looks to be the package name.
So change below line to the Activity class Name. Use the Eclipse Manifest editor rather than adding manually
<activity
android:name="com.domiq.androidappp"

You need to remove the android:permission="string" and android:permission="string". It looks like you just copied pasted that incorrectly. You are supposed to replace "string" with the proper values.
Also your android:name under your Activity should be the Activity name, e.g. android:name="com.domiq.androidapp.MyActivity".

Android app crashes on load - classNotFoundException

This has been driving me mad for a couple of days :)
IDEA is my weapon of choice. During an editing session of inconsequential changes (or so I thought) of adjusting layouts, nudging buttons a few pixels left to line up etc I compiled and ran the project. I got a ClassNotFoundException when my app starts. It is thrown by java.lang.Bootloader. I put a breakpoint on the call to the Bootloader and can see that the offending class is my main application class. Here's how it looks:
public class Rands extends Application{
public static SharedPreferences preferences;
private static ArrayList<Favourite> favourites;
private static Rands instance;
public Rands(){
instance = this;
}
and in the manifest:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="rands.mycompany.com"
android:installLocation="preferExternal"
android:versionCode="8"
android:versionName="0.8">
<uses-sdk android:minSdkVersion="8" />
<uses-permission android:name="android.permission.VIBRATE" />
<application android:name="rands.mycompany.com.Rands"
android:icon="#drawable/icon"
android:label="#string/app_name">
<activity android:name="rands.mycompany.com.RandsMainActivity"
android:theme="#android:style/Theme.Translucent.NoTitleBar"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name="rands.mycompany.com.MainMenuActivity"
android:theme="#android:style/Theme.Translucent.NoTitleBar"
android:label="MainMenuActivity"/>
This is where things get funky. There is NOTHING of relevance in logcat. I see the app copying, installing and starting then I get the exception. The exception occurs before the constructor on my application class is called. If I load the project in Eclipse, it works fine. I load in back into IDEA and I get the exception. I have two phones, a Desire with 2.3 and a Tmobile Pulse (Huawei) with 2.2. It happens on both phones and in the emulator. If I run the app outside the IDE (i.e. from the launcher) it runs fine.
I make these assumptions:
As there is nothing in logcat, it smells like a platform bug
As the project works fine in Eclipse, I'm assuming that my manifest and application class are fine.
I've also tried
<application android:name=".Rands"
Any clues?
Cheers

I finished my project in Eclipse then came back for another go at this weird problem.
I have no idea why, but creating a new project from the existing sources worked right away.
I moved the project folder out of my workspace, deleted everything except my src and res folders (no assets) and the manifest then created a new project from existing sources.
Go figure...

you have already specify the package name in menifest tag so don't redeclare it in activity tag, below code will work for menifest.
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="rands.mycompany.com"
android:installLocation="preferExternal"
android:versionCode="8"
android:versionName="0.8">
<uses-sdk android:minSdkVersion="8" />
<uses-permission android:name="android.permission.VIBRATE" />
<application android:name="rands.mycompany.com.Rands"
android:icon="#drawable/icon"
android:label="#string/app_name">
<activity android:name=".Rands"
android:theme="#android:style/Theme.Translucent.NoTitleBar"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".MainMenuActivity"
android:theme="#android:style/Theme.Translucent.NoTitleBar"
android:label="MainMenuActivity"/>

Your Application and Activity objects are both named as "rands.mycompany.com.Rands" maybe that's the problem?