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java片段和ViewPager类CastException

我正在使用带有操作栏选项卡的viewpager,布局中有两个片段,问题是我遇到了类强制转换异常

我的xml文件如下所示

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

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

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

我的活动歌曲和相册中有两个标签

它在纵向模式下正确加载,但在横向模式下显示类强制转换异常

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$1.onItemClick(AlbumFragMent.java:52)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at 安卓.widget.AdapterView.performItemClick(AdapterView.java:284)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at 安卓.widget.AbsListView$PerformClick.run(AbsListView.java:1696)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at 安卓.os.Handler.handleCallback(Handler.java:587)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at 安卓.os.Handler.dispatchMessage(Handler.java:92)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at 安卓.os.Looper.loop(Looper.java:123)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at 安卓.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.安卓.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at com.安卓.internal.os.ZygoteInit.main(ZygoteInit.java:626)
12-08 04:30:08.198: E/AndroidRuntime(2166):     at dalvik.system.NativeStart.main(Native Method)

错误显示在这里

在AlbumFragMent中,双模式的类代码为

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();

    }
}

SongFragment类中

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();
    }
}

两者唯一的区别是调用的detailfragment类

我做错了吗

还有什么我们需要处理的吗


共 (1) 个答案

  1. # 1 楼答案

    好吧,我来解决这个。。。这个解决方案有点奇怪,但对我来说很有效

    我决定使用公共细节片段类,而不是为每个选项卡使用单独的片段类。并根据当前选择显示内容