10A中Iterator viewer 如何实现循环查看

可以修改如下函数，其中有注释//mtk的部分是新加的语句 
1. mmi_um_query_indexing() 
if (i == 0) 
{ 
    /* First one */ 
    result->next_msg_id = ((srv_um_msg_node_struct *)data_list->list)[i + 1].msg_id; 
    result->next_msg_type = ((srv_um_msg_node_struct *)data_list->list)[i + 1].msg_type; 
    result->next_launch_func_ptr = mmi_um_ui_adp_get_viewer_ptr(result->next_msg_type); 
    result->prev_msg_id = ((srv_um_msg_node_struct *)data_list->list)[(data_list->msg_number) -1].msg_id;//mtk 
           result->prev_msg_type = ((srv_um_msg_node_struct *)data_list->list)[(data_list->msg_number) -1].msg_type;//mtk 
           result->prev_launch_func_ptr = mmi_um_ui_adp_get_viewer_ptr(result->prev_msg_type);//mtk     
} 
else if (i == (data_list->msg_number - 1)) 
{ 
    /* Last one */ 
    result->prev_msg_id = ((srv_um_msg_node_struct *)data_list->list)[i - 1].msg_id; 
    result->prev_msg_type = ((srv_um_msg_node_struct *)data_list->list)[i - 1].msg_type; 
    result->prev_launch_func_ptr = mmi_um_ui_adp_get_viewer_ptr(result->prev_msg_type); 
    result->next_msg_id = ((srv_um_msg_node_struct *)data_list->list)[0].msg_id;        //mtk 
    result->next_msg_type = ((srv_um_msg_node_struct *)data_list->list)[0].msg_type;    //mtk 
    result->next_launch_func_ptr = mmi_um_ui_adp_get_viewer_ptr(result->next_msg_type); //mtk 
} 
else 
{ 
2.wgui_mv_right_key_down_handler()，注释掉判断语句 
// if(g_wgui_mv_cat_cntx.curr_msg_num < g_wgui_mv_cat_cntx.total_msg_num) 
wgui_mv_left_key_down_handler() 
//if(g_wgui_mv_cat_cntx.curr_msg_num > 1) 
3.mmi_umms_app_ui_property_status_screen_draw_func()，去掉对第一条最后一条的判断 
#ifdef __MMI_MMS_ITERATOR_VIEWER__ 
    /*             
    if(index_num == 1) 
    { 
        lnk_func = NULL; 
    } 
    if(index_num == total_num) 
    { 
        rnk_func = NULL; 
    }*/