列表操作

布满荆棘的人生 2022-09-24 11:28 107阅读 0赞

最近在项目中，需要对列表进行操作

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进行上移&下移操作

JSP

<tbody id="TableData" class="dataContainer" datakey="forumList">
            <s:iterator value="#forumList" status="status">
    			<tr class="TableDetail1 template">
    				<td>${name} </td>
    				<td>${description} </td>
    				<td>
    				<span style="white-space:pre">	</span><s:a action="forumManage_delete?id=%{id}" onClick="return delConfirm()" >删除</s:a>
    					<s:a action="forumManage_editUI?id=%{id}" >修改</s:a>
    <span style="white-space:pre">					</span><s:a action="forumManage_moveUp?id=%{id}" >上移</s:a>
    					<s:a action="forumManage_moveDown?id=%{id}" >下移</s:a> 	
    				</td>
    			</tr>
    			</s:iterator>
            </tbody>

Action

@Controller
    @Scope("prototype")
    public class ForumManageAction extends BaseAction<Forum>
    {
    <span style="white-space:pre">	</span>//其他代码省略
    	
    	//上移
    	public String moveUp() throws Exception
    	{
    		forumService.moveUp(model.getId());
    		return "toList";
    	}
    	
    	//下移
    	public String moveDown() throws Exception
    	{
    		forumService.moveDown(model.getId());
    		return "toList";	
    	}
    }

Service实现

@Service
    @Transactional
    @SuppressWarnings("unchecked")
    public class ForumServiceImpl extends DaoSupportImpl<Forum> implements ForumService
    {
    <span style="white-space:pre">	</span>//重写findAll方法(根据position字段排序)
    	@Override
    	public List<Forum> findAll()
    	{
    		return getSession().createQuery(
    				"From Forum f ORDER BY f.position")
    				.list();
    	}
    	
    	@Override
    	public void moveDown(Long id)
    	{
    		//找出相关的Forum 
    		Forum forum = getById(id);         //当前要移动的Forum
    		Forum other  = (Forum)getSession().createQuery(
    								"FROM Forum f WHERE f.position>? ORDER BY f.position ASC ")
    								.setParameter(0, forum.getPosition())
    								.setFirstResult(0)
    								.setMaxResults(1)
    								.uniqueResult();						//下面的那个FOrum
    		
    		//最下面的不能下移
    		if (other == null)
    		{
    			return;
    		}
    		
    		//交换Position的位置
    		int temp = forum.getPosition();		//设置一个中间值
    		forum.setPosition(other.getPosition());
    		other.setPosition(temp);
    		//保存到数据库中
    		getSession().update(other);
    		getSession().update(forum);
    	}
    
    	@Override
    	public void moveUp(Long id)
    	{
    		//找出相关的Forum 
    		Forum forum = getById(id);         //当前要移动的Forum
    		Forum other  = (Forum)getSession().createQuery(
    								"FROM Forum f WHERE f.position<? ORDER BY f.position DESC ")
    								.setParameter(0, forum.getPosition())
    								.setFirstResult(0)
    								.setMaxResults(1)
    								.uniqueResult();						//上面的那个FOrum
    		
    		//最上面的不能上移
    		if (other == null)
    		{
    			return;
    		}
    		//交换Position的位置
    		int temp = forum.getPosition();		//设置一个中间值
    		forum.setPosition(other.getPosition());
    		other.setPosition(temp);
    		//保存到数据库中
    		getSession().update(other);
    		getSession().update(forum);
    	}
    
    }

增强用户体验，不能点的按钮需要变灰

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<tbody id="TableData" class="dataContainer" datakey="forumList">
            <s:iterator value="#forumList" status="status">
    			<tr class="TableDetail1 template">
    				<td>${name} </td>
    				<td>${description} </td>
    				<td>
    					<s:a action="forumManage_delete?id=%{id}" onClick="return delConfirm()" >删除</s:a>
    					<s:a action="forumManage_editUI?id=%{id}" >修改</s:a>
    					
    					<s:if test="#status.first">
    						<span class="disabled">上移</span>
    					</s:if>
    					<s:else>
    						<s:a action="forumManage_moveUp?id=%{id}" >上移</s:a>
    					</s:else>
    					
    					<s:if test="#status.last ">
    						<span class="disabled">下移</span>
    					</s:if>
    					<s:else>
    						<s:a action="forumManage_moveDown?id=%{id}" >下移</s:a> 
    					</s:else>	
    				</td>
    			</tr>
    			</s:iterator>
            </tbody>

增加Status属性，可以查看源码IteratorStatus

* <ul>
     * <li>index: current iteration index, starts on 0 and increments in one on every iteration</li>
     * <li>count: iterations so far, starts on 1. count is always index + 1</li>
     * <li>first: true if index == 0</li>
     * <li>even: true if (index + 1) % 2 == 0</li>
     * <li>last: true if current iteration is the last iteration</li> 
     * <li>odd: true if (index + 1) % 2 == 1</li>
     * </ul>

[Center]: /images/20220719/91085d4d15cc4264b88ca48fd0f7f0f2.png
[Center 1]: /images/20220719/8580d54a40164a73b15c40dd111a5d07.png