问ClassCastException与TableLayout在PopupWindow中

EN

    Button quickView = (Button) convertView.findViewById(R.id.openpopup);
       quickView.setOnClickListener(new OnClickListener() 
       { 
           @Override
           public void onClick(View v) 
           {
               //create new popupWindow with popuptable as its layout
                LayoutInflater inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                PopupWindow pw = null;
                View popupView = inflater.inflate(R.layout.popuptable, null);
                if (scores[0] == null ) {
                    pw = new PopupWindow(popupView, 100, 100, true); 
                    TextView score = (TextView) popupView.findViewById(R.id.popupmessage);
                    score.setText("Error!");
                } else {

                    pw = new PopupWindow(popupView, 200, 200, true);  //wrap content?
                    for (int i = 0; i < z; i++) {
                        //create a new row here 
                        View rowView = inflater.inflate(R.layout.table_row, null); //this is the template for each view

                        //add info to the row
                        TextView tag = (TextView) rowView.findViewById(R.id.tag); //id within the layout 
                        tag.setText(tags[i]);

                        //insert the new row  into the popuptable view
                        View insertPoint = (TextView) popupView.findViewById(R.id.popuptitle);
                        ((ViewGroup) insertPoint).addView(rowView, i, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));


                    }
                }

                pw.showAtLocation(popupView, Gravity.CENTER, 0, 0);

           }

       });

<TableLayout
xmlns:custom="http://schemas.android.com/apk/res/com.tforan.blobtag4" 
xmlns:android="http://schemas.android.com/apk/res/android"    
android:id="@+id/popup"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/fitScoreTable"
android:shrinkColumns="0"
android:layout_marginTop="5dp" >
<TextView
    android:id="@+id/popuptitle"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginTop="5dp"
    android:textIsSelectable="true"
    android:text="Tags"
    android:textColor="#000000"
    android:textSize="14dp" />
<TextView
    android:id="@+id/popupmessage"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginTop="5dp"
    android:textIsSelectable="true"
    android:textColor="#000000"
    android:textSize="14dp" />  
</TableLayout>

09-13 13:26:57.426: E/AndroidRuntime(2594): FATAL EXCEPTION: main
09-13 13:26:57.426: E/AndroidRuntime(2594): java.lang.ClassCastException: android.widget.TextView
09-13 13:26:57.426: E/AndroidRuntime(2594):     at com.tforan.blobtag4.ResultsAdapter$1.onClick(ResultsAdapter.java:125)
09-13 13:26:57.426: E/AndroidRuntime(2594):     at android.view.View.performClick(View.java:2533)
09-13 13:26:57.426: E/AndroidRuntime(2594):     at android.view.View$PerformClick.run(View.java:9299)
09-13 13:26:57.426: E/AndroidRuntime(2594):     at android.os.Handler.handleCallback(Handler.java:587)
09-13 13:26:57.426: E/AndroidRuntime(2594):     at android.os.Handler.dispatchMessage(Handler.java:92)
09-13 13:26:57.426: E/AndroidRuntime(2594):     at android.os.Looper.loop(Looper.java:150)
09-13 13:26:57.426: E/AndroidRuntime(2594):     at android.app.ActivityThread.main(ActivityThread.java:4358)
09-13 13:26:57.426: E/AndroidRuntime(2594):     at java.lang.reflect.Method.invokeNative(Native Method)
09-13 13:26:57.426: E/AndroidRuntime(2594):     at java.lang.reflect.Method.invoke(Method.java:507)
09-13 13:26:57.426: E/AndroidRuntime(2594):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:849)
09-13 13:26:57.426: E/AndroidRuntime(2594):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:607)
09-13 13:26:57.426: E/AndroidRuntime(2594):     at dalvik.system.NativeStart.main(Native Method)