Develop Reference

Ionic/Cordova app does not find MainActivity

My app (Ionic 5 + Cordova 9.1.0) crashes when I try to start it on an Android 11 phone. When I look into the logs with logcat I see that the main activity is not found:
10-21 16:31:29.281 5300 5300 E AndroidRuntime:
java.lang.RuntimeException: Unable to instantiate activity
ComponentInfo{de.meingolfclub.myapp/de.meingolfclub.myapp.MainActivity}:
java.lang.ClassNotFoundException: Didn't find class
"de.meingolfclub.myapp.MainActivity" on path: DexPathList[[zip file
"/data/app/~~7FMRVcshmIuFxkzCRS8B2g==/de.meingolfclub.myapp-kbOatrQJj_K4ZJHsuXESTg==/base.apk"],nativeLibraryDirectories=[/data/app/~~7FMRVcshmIuFxkzCRS8B2g==/de.meingolfclub.myapp-kbOatrQJj_K4ZJHsuXESTg==/lib/arm64,
/data/app/~~7FMRVcshmIuFxkzCRS8B2g==/de.meingolfclub.myapp-kbOatrQJj_K4ZJHsuXESTg==/base.apk!/lib/arm64-v8a,
/system/lib64, /system_ext/lib64]]
I googled a bit and it seems to be related to multiDex functionality of Android, but I have no idea how to fix this in an Ionic/Cordova project.
What can I do to solve this problem?

I solved it.
There was a wrong package name in MainActivity. After removing the Android platform and adding it again the package name was correct. And after a build the starts again.

CoreComponentFactoryDidn't find class "android.support.v4.app.CoreComponentFactory"

I got sudden crash in my google pixel 2 having android 9 version.
Is there any hint what is the reason behind that and it is not reproducible every time.
detail logs...
Didn't find class "android.support.v4.app.CoreComponentFactory" on
path: DexPathList[[zip file
"/data/app/com.google.android.deskclock-o_Iury9TRKVebStZjRrd0g==/base.apk"],nativeLibraryDirectories=[/data/app/com.google.android.deskclock-o_Iury9TRKVebStZjRrd0g==/lib/arm64,
/system/lib64]]

Just clean the build and run it will go away

Android application signed with same key store using same sharedUserId crashes due to java.lang.RuntimeException: Unable to instantiate activity

I want to make some Android applications running in the same process, so I give those apps's AndroidManifest the same sharedUserId:
< manifest xmlns:android="http://schemas.android.com/apk/res/android"
...
android:sharedUserId="aaa.bbb" >
and assign each apps's application the same process:
< application
...
android:process="com.mytest" >
It works in android 4.4.4 , all the Applications run in the same Process.
But crash happened in android 6.0.1.
When I run the second app, it crashes due to:
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.myapplication/com.example.myapplication.MainActivity}:
java.lang.ClassNotFoundException: Didn't find class "com.example.myapplication.MainActivity" on path:
DexPathList[[zip file "/data/app/com.example.myapplication-1/base.apk"],nativeLibraryDirectories=[/data/app/com.example.myapplication-1/lib/arm, /vendor/lib, /system/lib]]
after the system kill the Process, the second app can run and crashes if I run the first application.
It seem that applications can not run in the same process in the same time and I do not know why.

Each APK has its own ClassLoader. An article talking about this.
So it's normal you can't access a class of another APK.
It seems that a security bug was fix between Kitkat and Marshmallow.
Why you need this system ?
If it's to share data between application, you could use ContentProvider
If it's to launch Activity or Service, you could use Intent with action.

I fixed it !
disable the options in Android studio ant it works !

GCM push noti in Unity3d causes gms.iid.InstanceID classnotfound

I have made an Android plugin to use GCM in my Unity app. When I try to start the RegistrationIntentService (readymade example class from Android Developer Manual site), it causes a crash with the exception
Caused by: java.lang.ClassNotFoundException: Didn't find class "com.google.android.gms.iid.InstanceID" on path: DexPathList[[zip file "/data/app/com.ex.test-1/base.apk"],nativeLibraryDirectories=[/data/app/com.ex.test-1/lib/arm, /vendor/lib, /system/lib]]
I have imported the play-services-9.2.0.unitypackage, without any success. Any help?

For anyone who might want to look for this question answered, I found the solution. The InstanceID.class is not included in the play-services-9.2.0.unitypackage, so include the play-services-iid-9.0.2.aar in the Android -> Plugins folder.

Achart 1.0.0 example android API 15

Alright, I have been messing with this for a few hours now, and I can't figure out why I'm having issues.
I have been following the example from
http://xebee.xebia.in/2010/08/31/exploring-android-charting-and-graphs-solutions/
AND
I have already tried to create a fix using this link:
Android achartengine simple pie chart
AND
I have tried using the demo that achartengine provides Here.
But that project crashed immediately after selecting a chart type on my android device.
I am new to android, and have followed those two resources almost exactly, and I'm getting this:
Conversion to Dalvik format failed with error 1
None of my src files are showing up with errors, and I have added the new activity in AndroidManifest.xml and achartengine-1.0.0.jar into my libs folder
I am using Android 4.0.3 API Level 15
I can't believe I am having this much trouble with such a seemingly simple task, but I appreciate your help.
EDIT:
this is a snippit from my log:
07-04 17:03:58.650: E/AndroidRuntime(21611): FATAL EXCEPTION: main
07-04 17:03:58.650: E/AndroidRuntime(21611): java.lang.RuntimeException: Unable to start activity ComponentInfo{axiodesigns.com.caffeinezone2/axiodesigns.com.caffeinezone2.CzMain}: android.content.ActivityNotFoundException: Unable to find explicit activity class {axiodesigns.com.caffeinezone2/org.achartengine.GraphicalActivity}; have you declared this activity in your AndroidManifest.xml?
I have no activity called GraphicalActivity, and even after i added:
<activity android:name="GraphicalActivity"></activity>
I received the exact same error
quite a headscratcher

Found the fix, my build path was not recognizing that I had the .jar in my libs folder.
This fixed it:
The application AChartengine has stopped unexpectedly. Please try again
Thanks for the help all