Question

I am trying to return 2 different type of views in the BaseAdapter’s getView method according to the position .

But I am getting ClassCastException. Below is my code:

public View getView(final int position, View convertView, ViewGroup parent) {
    if(position != 5){

        WebPageView web;
        if(convertView == null){

            web = new WebPageView(mContext, new Point(parent.getWidth(), parent.getHeight()), parent);

    } else {
        web = (WebPageView) convertView;

    }

        web.setPage("http://yahoo.com");
        return web;
    }else{
    final PageView pageView;
    if (convertView == null) {
        pageView = new PageView(mContext);
    } else {
        pageView = (PageView) convertView;
    }


    return pageView;
}
}

But I am getting always ClassCastException. When I am using WebPageView or PageView alone in getView, I am not getting the exception.

Anyone having any idea?

Below is my logcat output.

10-18 18:03:59.250: E/AndroidRuntime(31390): FATAL EXCEPTION: main
10-18 18:03:59.250: E/AndroidRuntime(31390): java.lang.ClassCastException: com.getit.WebPageView cannot be cast to com.getit.PageView
10-18 18:03:59.250: E/AndroidRuntime(31390):    at com.getit.PageAdapter.getView(PageAdapter.java:94)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at com.getit.CustomGalleryView.getOrCreateChild(CustomGalleryView.java:467)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at com.getit.CustomGalleryView.onLayout(CustomGalleryView.java:422)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.View.layout(View.java:13754)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.ViewGroup.layout(ViewGroup.java:4364)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.widget.RelativeLayout.onLayout(RelativeLayout.java:948)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.View.layout(View.java:13754)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.ViewGroup.layout(ViewGroup.java:4364)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.widget.FrameLayout.onLayout(FrameLayout.java:448)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.View.layout(View.java:13754)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.ViewGroup.layout(ViewGroup.java:4364)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1649)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1507)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.widget.LinearLayout.onLayout(LinearLayout.java:1420)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.View.layout(View.java:13754)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.ViewGroup.layout(ViewGroup.java:4364)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.widget.FrameLayout.onLayout(FrameLayout.java:448)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.View.layout(View.java:13754)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.ViewGroup.layout(ViewGroup.java:4364)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:1868)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1689)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1000)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4214)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.Choreographer$CallbackRecord.run(Choreographer.java:725)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.Choreographer.doCallbacks(Choreographer.java:555)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.Choreographer.doFrame(Choreographer.java:525)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:711)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.os.Handler.handleCallback(Handler.java:615)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.os.Handler.dispatchMessage(Handler.java:92)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.os.Looper.loop(Looper.java:137)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at android.app.ActivityThread.main(ActivityThread.java:4745)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at java.lang.reflect.Method.invokeNative(Native Method)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at java.lang.reflect.Method.invoke(Method.java:511)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
10-18 18:03:59.250: E/AndroidRuntime(31390):    at dalvik.system.NativeStart.main(Native Method)

Answer 1

You get this error because you try to recycle a view that was already cast to another object.I don’t know if you use custom objects or not as if both were extending a common class it would have worked.You can do 2 things:

1:Check if convertview is an istance of your custom object.This ensures that you not try to cast pageview to a webview or viceversa

if (convertView == null || !convertView instanceof PageView) {
    pageView = new PageView(mContext);
} else {
    pageView = (PageView) convertView;
}

same check for webview aswell.

2:Instantiate every time a new object

if(position != 5){
WebPageView web;
web = new WebPageView(mContext, new Point(parent.getWidth(), parent.getHeight()), parent);
web.setPage("http://yahoo.com");
return web;
}else{
final PageView pageView;
pageView = new PageView(mContext);
return pageView;
}

not really advised but still…