Can't find class MainActivity (imported project)

Question

So I imported an android project and after struggling for a while when I was finally done, I compiled the app and it crashed.

This is the logcat file:

07-16 23:02:23.700: E/AndroidRuntime(23092): FATAL EXCEPTION: main
07-16 23:02:23.700: E/AndroidRuntime(23092): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{si.dvanadva.evanturist/si.dvanadva.evanturist.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "si.dvanadva.evanturist.MainActivity" on path: /data/app/si.dvanadva.evanturist-2.apk
07-16 23:02:23.700: E/AndroidRuntime(23092):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2106)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at android.app.ActivityThread.access$600(ActivityThread.java:141)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at android.os.Handler.dispatchMessage(Handler.java:99)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at android.os.Looper.loop(Looper.java:137)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at android.app.ActivityThread.main(ActivityThread.java:5041)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at java.lang.reflect.Method.invokeNative(Native Method)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at java.lang.reflect.Method.invoke(Method.java:511)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at dalvik.system.NativeStart.main(Native Method)
07-16 23:02:23.700: E/AndroidRuntime(23092): Caused by: java.lang.ClassNotFoundException: Didn't find class "si.dvanadva.evanturist.MainActivity" on path: /data/app/si.dvanadva.evanturist-2.apk
07-16 23:02:23.700: E/AndroidRuntime(23092):    at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:65)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at android.app.Instrumentation.newActivity(Instrumentation.java:1054)
07-16 23:02:23.700: E/AndroidRuntime(23092):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2097)

I can see from this line:

07-16 23:02:23.700: E/AndroidRuntime(23092): Caused by: java.lang.ClassNotFoundException: Didn't find class "si.dvanadva.evanturist.MainActivity" on path: /data/app/si.dvanadva.evanturist-2.apk

That there is a problem finding MainActivity class. But why?

This is how I imported the project:

Imported raw project (without libraries)
Added jars to libs folder in the project
Added missing build path for jars
Imported three library projects (the original project detected them)

Those three library projects are all in the same folder as the original project (in case I placed them wrong or something)

If you need any additional info please let me know, I need to solve this problem

Packages and their content:

enter image description here

AndroidManifest full code:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="si.dvanadva.evanturist"
android:versionCode="7"
android:versionName="1.1.2" 
android:installLocation="preferExternal">

<!-- ZA MAPE -->
<permission
    android:name="com.dd.evanturist.permission.MAPS_RECEIVE"
    android:protectionLevel="signature"/>
<uses-permission android:name="com.dd.evanturist.permission.MAPS_RECEIVE"/>

  <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
  <uses-permission android:name="android.permission.INTERNET"/>
  <uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES"/>
  <!-- External storage for caching. -->
  <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
  <!-- My Location -->
  <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
  <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
  <!-- Maps API needs OpenGL ES 2.0. -->
  <uses-feature
    android:glEsVersion="0x00020000"
    android:required="true"/>
  <!-- End of copy. -->

<!-- QR STUFF -->

<uses-permission android:name="android.permission.CAMERA"/>
<uses-permission android:name="android.permission.FLASHLIGHT"/>

<uses-sdk
    android:minSdkVersion="8"
    android:targetSdkVersion="17" />

<application
    android:allowBackup="true"
    android:name=".MyApplication"
    android:icon="@drawable/ic_launcher"
    android:label="@string/evanturist"
    android:theme="@style/AppTheme" >
    <meta-data
        android:name="com.google.android.maps.v2.API_KEY"
        android:value="AIzaSyDK5zGCwh3awW08BOAwupjU4hw8750WuLM"/>
    <activity
        android:name=".MainActivity"
        android:label="@string/evanturist" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity android:name=".DBActivity"></activity>
    <activity android:name=".DbTestActivity"></activity>
    <activity android:name=".PlaceItemActivity"></activity>
    <activity android:name=".CheckpointsActivity"></activity>
    <activity android:name=".OptionsActivity"></activity>
    <activity android:name=".MapDirectionsActivity"></activity>
    <activity android:name=".VictoryActivity"></activity>
    <activity android:name=".QrActivity"
        android:screenOrientation="landscape"
        android:theme="@android:style/Theme.NoTitleBar.Fullscreen"></activity>
    <activity android:name=".QrPortraitActivity"
        android:screenOrientation="portrait" android:theme="@android:style/Theme.NoTitleBar"></activity>

</application>

Export tab at build paths:

enter image description here

@gunar Sorry, I don't quite understand your question. I am using eclipse, but what do you mean? — Guy, Jul 16 '13 at 21:17
Your `MainActivity` extends from `Activity` or from `FragmentActivity`? — gunar, Jul 16 '13 at 21:19
Did you take a look at AndroidManifest.xml to check if MainActivity is correctly declared? — ᗩИᎠЯƎᗩ, Jul 17 '13 at 00:27
@Andreaoid I'm pretty sure it'd declared correctly, but I really hope you're on to something here :P Please tell me if you think anything is wrong — Guy, Jul 17 '13 at 05:55
have you tried this? http://stackoverflow.com/questions/17273218/android-unable-to-instantiate-activity-didnt-find-class-on-path — DucTran, Jul 17 '13 at 10:34
Yes, I already did this. Please check my edit on my original post though, I posted a screenshot of my export tab, if problem lies there — Guy, Jul 17 '13 at 11:09

score 3 · Accepted Answer · answered Jul 21 '13 at 11:26

Problem solved!!

The entire problem was caused by Google Play Services library project. When someone sent me this project, he also attached all three library projects needed for the project. I then added all three library project directly from the file that he sent me.

Now the thing is, you always need to add google play services from SDK download location (not from anywhere else - external sources), so I just removed the current google play services and added the ones that I downloadad with the SDK manager and the problem was solved.

score 2 · Answer 2 · answered Jul 17 '13 at 06:58

2

1) Keep all activities under same package[say com.compname.proj.views].

2) Ensure in manifest, package attribute is set to the above package[i.e com.compname.proj.views].

3) In manifest, under all activity tag, make sure android:name attribute has values matching to below pattern:

    android:name=".<your activity class name>"

Ex: android:name=".SomeActivity"

My point is not to use package name + activity class name for manifest activity declaration.

Once you are sure about above points, if still problem persists, then :

Delete bin folder.
Rebuild your project and run.

answered Jul 17 '13 at 06:58

Chandan Adiga

576
4
14

Thank you for your answer! I have three packages but only activities from the main package are declared in the manifest file. I did change the manifest declaration to .activityname (I removed the package name) and it didn't work. I also tried removing bin and cleaning project but the error remains the same. Please check my edited original post where I posted a picture of all packages and their content and manifest file. – Guy Jul 17 '13 at 10:21
If you are having previous version apk in your device/emulator, then uninstall and install latest version form recent build.From crash log /data/app/si.dvanadva.evanturist-2.apk indicates that there are 2 builds(apks) in the system. Also there is a possibility that your project settings/configurations are not yet effective while building your app. This could be due to caching of project properties by eclipse. – Chandan Adiga Jul 17 '13 at 10:43
I tried removing the previous version and installing the newest build but it didn't work. How can I fix the problem with 2 builds and settings/configurations? Please also check my new edit, I posted a screenshot of export tab at build paths, maybe the problem is there? – Guy Jul 17 '13 at 11:07

Can't find class MainActivity (imported project)

2 Answers2