android警告对话框显示WindowManager $ BadTokenException

Question

我已经实现了以下代码来显示自定义警告对话框但是当我调用此对话框时它显示异常：

WindowManager.BadTokenException

public static void showAlertDialog(final String title, String message,
            final Context context, final boolean redirectToPreviousScreen) {
        AlertDialog.Builder alertbox = new AlertDialog.Builder(context);
        alertbox.setMessage(message);
        alertbox.setTitle(title);

        alertbox.setNeutralButton("Ok", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface arg0, int arg1) {

            }
        });
        try{
            alertbox.show();    
        }catch (Exception b) {

        }