Question

I am using viewpager with action-bar tab and I am have two fragment in layout, and the problem is I am getting class-cast-exception

my xml file is look like below

 <LinearLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:orientation="horizontal" >

        <android.support.v4.view.ViewPager
            android:id="@+id/pager"
            android:layout_width="0px"
            android:layout_height="match_parent"
            android:layout_weight="2.5" />

        <FrameLayout
            android:id="@+id/fragment_details"
            android:layout_width="0px"
            android:layout_height="match_parent"
            android:layout_weight="2" />
    </LinearLayout>

and I have two tabs in my activity songs and album.

It loads correctly in portrait mode but in, landscape mode it shows class cast exception.

12-08 04:30:08.198: E/AndroidRuntime(2166): FATAL EXCEPTION: main
12-08 04:30:08.198: E/AndroidRuntime(2166): java.lang.ClassCastException: com.nix.music.activity.fragments.SongDetailsFragment
12-08 04:30:08.198: E/AndroidRuntime(2166):     at com.nix.music.activity.fragments.AlbumFragMent.showDetails(AlbumFragMent.java:81)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at com.nix.music.activity.fragments.AlbumFragMent.access$0(AlbumFragMent.java:77)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at com.nix.music.activity.fragments.AlbumFragMent$1.onItemClick(AlbumFragMent.java:52)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at android.widget.AdapterView.performItemClick(AdapterView.java:284)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at android.widget.AbsListView$PerformClick.run(AbsListView.java:1696)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at android.os.Handler.handleCallback(Handler.java:587)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at android.os.Handler.dispatchMessage(Handler.java:92)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at android.os.Looper.loop(Looper.java:123)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at android.app.ActivityThread.main(ActivityThread.java:4627)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at java.lang.reflect.Method.invokeNative(Native Method)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at java.lang.reflect.Method.invoke(Method.java:521)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at dalvik.system.NativeStart.main(Native Method)

error is shown in here

in AlbumFragMent class code for dual mode is

if (mDualPane) {
    AlbumDetailFragment details = (AlbumDetailFragment) getFragmentManager()
            .findFragmentById(R.id.fragment_details);
    if (details == null || details.getShownIndex() != index) {
        // Make new fragment to show this selection.
        details = AlbumDetailFragment.newInstance(index);

        // Execute a transaction, replacing any existing fragment
        // with this one inside the frame.
        FragmentTransaction ft = getFragmentManager()
                .beginTransaction();
        ft.replace(R.id.fragment_details, details);
        ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
        ft.commit();

    }
}

and in SongFragment class

if (mDualPane) {
    getListView().setItemChecked(index, true);

    SongDetailsFragment details = (SongDetailsFragment) getFragmentManager()
            .findFragmentById(R.id.fragment_details);
    if (details == null || details.getShownIndex() != index) {
        // Make new fragment to show this selection.
        details = SongDetailsFragment.newInstance(index);

        // Execute a transaction, replacing any existing fragment
        // with this one inside the frame.
        FragmentTransaction ft = getFragmentManager()
                .beginTransaction();
        ft.replace(R.id.fragment_details, details);
        ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
        ft.commit();
    }
}

only difference in both is the Detail fragment class which is calling.

Am I doing it wrong?

Is there anything else we need to take care of.

Answer 1

okay i solve this… the solution is kind of weird but works for me.

I have decides to go with common detail-fragment class rather then having separate fragment class for each tab. and display the content based on the current current selection.