使用actionbarsherlock库的Android ClassNotFoundException

Question

I keep getting the classnotfoundexception when trying to run my project on an emulator. I have looked around on here before posting this question, I have tried adding libraries to the build path, cleaning / building the project but still hasn't solved the issue.

The project was built from using an open source calendar project. So the name is weird, but doesn't have any affect on the build.

Here's the LogCat:

09-03 12:37:36.990: E/Trace(2272): error opening trace file: No such file or directory (2)
09-03 12:37:37.439: W/dalvikvm(2272): Unable to resolve superclass of Lcom/squareup/timessquare/sample/DashboardActivity; (453)
09-03 12:37:37.482: W/dalvikvm(2272): Link of class 'Lcom/squareup/timessquare/sample/DashboardActivity;' failed
09-03 12:37:37.482: D/AndroidRuntime(2272): Shutting down VM
09-03 12:37:37.482: W/dalvikvm(2272): threadid=1: thread exiting with uncaught exception (group=0x40a13300)
09-03 12:37:37.540: E/AndroidRuntime(2272): FATAL EXCEPTION: main
09-03 12:37:37.540: E/AndroidRuntime(2272): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.squareup.timessquare.sample/com.squareup.timessquare.sample.DashboardActivity}: java.lang.ClassNotFoundException: com.squareup.timessquare.sample.DashboardActivity
09-03 12:37:37.540: E/AndroidRuntime(2272):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1983)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at android.app.ActivityThread.access$600(ActivityThread.java:130)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at android.os.Handler.dispatchMessage(Handler.java:99)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at android.os.Looper.loop(Looper.java:137)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at android.app.ActivityThread.main(ActivityThread.java:4745)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at java.lang.reflect.Method.invokeNative(Native Method)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at java.lang.reflect.Method.invoke(Method.java:511)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at dalvik.system.NativeStart.main(Native Method)
09-03 12:37:37.540: E/AndroidRuntime(2272): Caused by: java.lang.ClassNotFoundException: com.squareup.timessquare.sample.DashboardActivity
09-03 12:37:37.540: E/AndroidRuntime(2272):     at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at android.app.Instrumentation.newActivity(Instrumentation.java:1053)
09-03 12:37:37.540: E/AndroidRuntime(2272):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1974)

And here's the class declared in the manifest:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.squareup.timessquare.sample"
    android:versionCode="1"
    android:versionName="1.0">

        <uses-sdk
        android:minSdkVersion="7"
        android:targetSdkVersion="17" />


    <application
        android:label="@string/app_name"
        android:icon="@drawable/supporticon"
        android:debuggable="true"
        android:supportsRtl="true">

        <activity
            android:name=".DashboardActivity"
            android:label="@string/app_name"
            android:configChanges="orientation|screenSize|keyboardHidden"
            >

            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

Here's the class content:

public class DashboardActivity extends SherlockFragmentActivity {

    ActionBar mActionBar;
    ViewPager mPager;
    Tab tab;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.dashboard);

        // Activate the navigation mode tabs
        mActionBar = getSupportActionBar();
        mActionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

        // Locate the view pager in dashboard.xml
        mPager = (ViewPager) findViewById(R.id.pager);

        // Activate the fragment manager
        FragmentManager fm = getSupportFragmentManager();

        // Capture view pager swipes
        ViewPager.SimpleOnPageChangeListener ViewPagerListener = new ViewPager.SimpleOnPageChangeListener() {
            @Override
            public void onPageSelected(int position) {
                super.onPageSelected(position);
                // Find the view pager position
                mActionBar.setSelectedNavigationItem(position);
            }
        };

        mPager.setOnPageChangeListener(ViewPagerListener);
        // Locate the adapter class
        ViewPagerAdapter viewpageradapter = new ViewPagerAdapter(fm);
        // Set the view pager adapter in ViewPager
        mPager.setAdapter(viewpageradapter);

        // Capture the button clicks
        ActionBar.TabListener tabListener = new ActionBar.TabListener() {

            @Override
            public void onTabUnselected(Tab tab, FragmentTransaction ft) {
                // Pass the position on tab click to view pager
                mPager.setCurrentItem(tab.getPosition());

            }

            @Override
            public void onTabSelected(Tab tab, FragmentTransaction ft) {
                // TODO Auto-generated method stub

            }

            @Override
            public void onTabReselected(Tab tab, FragmentTransaction ft) {
                // TODO Auto-generated method stub

            }
        };

        // Create the first tab
        tab = mActionBar.newTab().setText("Support Tab")
                .setTabListener(tabListener);
        mActionBar.addTab(tab);

        // Create the second tab
        tab = mActionBar.newTab().setText("Students Tab")
                .setTabListener(tabListener);
        mActionBar.addTab(tab);

    }

}

The only issues I can think of is that when I right click on my project > project properties > Android the actionbarsherlock reference has a red cross beside it. Even though there are no errors in my classes where I've used the library, I'm not sure if this has anything to do with it.

Any help would be appreciated, thanks.

Answer 1

The only issues I can think of is that when I right click on my project > project properties > Android the actionbarsherlock reference has a red cross beside it. Even though there are no errors in my classes where I've used the library, I'm not sure if this has anything to do with it.

Yes this definitely has something to do with it. This means that your project cannot find the place of your jar file, or lib project.

On that entry in the project properties page press the edit button and navigate to the jar file/ lib project folder again. Only when that red x turns into a green check will you be able to run your program correctly.