jquery.treeview使用

这几天项目中要用到树型结构，正好项目中用到了JQuery,所以就在网上找依赖JQuery的JS树，最终选择了 jquery.treeview.js,原因之一,它是JQuery官方发布的JS库，另一方面，看了一下它的文档，使用起来也是很简单的。经过一个小时的研究，终于搞定，现把它的使用方法做个简要的说明，以做笔记。

        要使用jquery.treeview.js，当然第一步是要把它下载下来，放入自己的工程中，然后在页面文件中引进 jquery.js,jquery.cookie.js,jquery.treeview.js,jquery.treeview.async.js四个库文件，其中最后一个是要使用异步加载结点的时候，要用到的，我的项目中已经用到了这个功能，在初始化树的时候，只加载顶层的数据，当点击顶层结点的时候，才会去加载下一层的结点，所有的数据都是通过ajax去后台取得到数据。

        将库文件引入后，下一步就是要定义一个列表UL:如这样：

<ul id="categorys">ul>

 

 树数据将会加载到这个UL里面

"text/javascript">
 $(document).ready(function(){
  $("#categorys").treeview({
   url: "category!ajaxTreeView"
  });
 });

 

这里面的意思就是当文档加载完成后，向后台CategoryAction获取数据，注意后台输出的数据必须是json格式的数据。

 下一步就是后台CategoryAction的数据输出部分了：

response.setHeader("Cache-Control", "no-cache");
response.setContentType("text/json;charset=UTF-8");
try {
 request.setCharacterEncoding("utf-8");
} catch (UnsupportedEncodingException e1) {
 e1.printStackTrace();
}

  response.setHeader("Cache-Control", "no-cache");
  response.setContentType("text/json;charset=UTF-8");
  try {
   request.setCharacterEncoding("utf-8");
  } catch (UnsupportedEncodingException e1) {
   e1.printStackTrace();
  }

 

 要将contenttype设置为"text/json"，第一次加载初始数据的时候，会向这个CategoryAction传递一个 get参数：root=source,所以后台可以判断root参数是否是source,如果是source,则代表是第一次加载数据，如果不是 source,则root参数传递的則是树结点的id.
 
 数据格式如下：

[
 {
  "text": "1. Pre Lunch (120 min)",
  "expanded": true,
  "classes": "important",
  "children":
  [
   {
    "text": "1.1 The State of the Powerdome (30 min)"
   },
    {
    "text": "1.2 The Future of jQuery (30 min)"
   },
    {
    "text": "1.2 jQuery UI - A step to richnessy (60 min)"
   }
  ]
 },
 {
  "text": "2. Lunch  (60 min)"
 },
 {
  "text": "3. After Lunch  (120+ min)",
  "children":
  [
   {
    "text": "3.1 jQuery Calendar Success Story (20 min)"
   },
    {
    "text": "3.2 jQuery and Ruby Web Frameworks (20 min)"
   },
    {
    "text": "3.3 Hey, I Can Do That! (20 min)"
   },
    {
    "text": "3.4 Taconite and Form (20 min)"
   },
    {
    "text": "3.5 Server-side JavaScript with jQuery and AOLserver (20 min)"
   },
    {
    "text": "3.6 The Onion: How to add features without adding features (20 min)",
    "id": "36",
    "hasChildren": true
   },
    {
    "text": "3.7 Visualizations with JavaScript and Canvas (20 min)"
   },
    {
    "text": "3.8 ActiveDOM (20 min)"
   },
    {
    "text": "3.8 Growing jQuery (20 min)"
   }
  ]
 }
]

[
 {
  "text": "1. Pre Lunch (120 min)",
  "expanded": true,
  "classes": "important",
  "children":
  [
   {
    "text": "1.1 The State of the Powerdome (30 min)"
   },
    {
    "text": "1.2 The Future of jQuery (30 min)"
   },
    {
    "text": "1.2 jQuery UI - A step to richnessy (60 min)"
   }
  ]
 },
 {
  "text": "2. Lunch  (60 min)"
 },
 {
  "text": "3. After Lunch  (120+ min)",
  "children":
  [
   {
    "text": "3.1 jQuery Calendar Success Story (20 min)"
   },
    {
    "text": "3.2 jQuery and Ruby Web Frameworks (20 min)"
   },
    {
    "text": "3.3 Hey, I Can Do That! (20 min)"
   },
    {
    "text": "3.4 Taconite and Form (20 min)"
   },
    {
    "text": "3.5 Server-side JavaScript with jQuery and AOLserver (20 min)"
   },
    {
    "text": "3.6 The Onion: How to add features without adding features (20 min)",
    "id": "36",
    "hasChildren": true
   },
    {
    "text": "3.7 Visualizations with JavaScript and Canvas (20 min)"
   },
    {
    "text": "3.8 ActiveDOM (20 min)"
   },
    {
    "text": "3.8 Growing jQuery (20 min)"
   }
  ]
 }
]

 

 

格式说明：上面的1. Pre Lunch (120 min) 结点中："expanded": true 代表这个结点下的child是展开的，children则是子结点的数据，节点3. After Lunch  (120+ min)有8个子结点，其中子结点中有一个结点3.6 The Onion: How to add features without adding features (20 min)，有一个id属性，同时hasChildren:true,表示其下面又有子结点，并且会向FetchProductTypeServlet传递参数为：root=id值，具体到这里就是root=36,那么点击这个结点的时候，后台就会接收到root=36这个值，然后我们就在具体应用中，通过数据库查询或者其它方式找到相对应的数据，然后将这些数据构造成treeview所需要的json数据，也即是上面所示格式的数据。

 

 

后台CategoryAction代码如下：

public String ajaxTreeView(){
    Struts2Utils.renderText(categoryHelper.generateJTVJsonString());
    return null;
}

	public String ajaxTreeView(){
		Struts2Utils.renderText(categoryHelper.generateJTVJsonString());
		return null;
	}

 

CategoryHelper代码如下：

package com.prl.action.admin.helper;

import java.util.List;

import javax.servlet.http.HttpServletRequest;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import org.springside.modules.web.struts2.Struts2Utils;

import com.prl.entity.Category;
import com.prl.service.CategoryManager;
import com.prl.service.jdbc.CategoryJdbcUtil;

@Repository
public class CategoryHelper {
    private static final Log log = LogFactory.getLog(CategoryHelper.class);
    @Autowired
    public CategoryManager categoryManager;
    @Autowired
    public CategoryJdbcUtil categoryJdbcUtil;

    // ========================= 产生jquery.treeview的jsonstring=================//
    public String generateJTVJsonString() {
        log.info("generateJTVJsonString start .....");
        HttpServletRequest request = Struts2Utils.getRequest();
        String id = request.getParameter("root");
        log.info("id:"+id);
        String output = "";
        if (id == null) {
            return "";
        } else if (id.equalsIgnoreCase("source")) {
            output = generateInitTreeString();
        } else {
            output = generateTreeChildNodeString(Long.parseLong(id));
        }
        log.info("generateJTVJsonString end,return:"+output);
        return output;
    }

    // 产生子节点jsonstring
    private String generateTreeChildNodeString(Long categoryId) {
        StringBuilder jsonString = new StringBuilder();
        jsonString.append("[");

        List categorys = categoryManager
                .findChildrenCategory(categoryId);
        if (categorys.isEmpty())
            return "";
        int i = 0;
        for (Category category : categorys) {
            if (i > 0) {
                jsonString.append(",");
            }
            jsonString.append(toJSONString(category));
            i++;
        }

        jsonString.append("]");
        return jsonString.toString();
    }

    private String toJSONString(Category category) {
        StringBuilder sb = new StringBuilder();
        sb.append(" {");
        sb.append("  \"text\": \"" + generateLinkString(category) + "\"");

        if (categoryJdbcUtil.hasChild(category)) {
            sb.append(",  \"id\":\"" + category.getCatId() + "\"");
            sb.append(",  \"hasChildren\":true");
        }
        sb.append(" }");
        return sb.toString();
    }

    private String generateLinkString(Category category) {
        String link = "+category.getCatId()+");' >" + category.getCatName() + "";
        //link = category.getCatName();
        return link;
    }

    private String generateInitTreeString() {
        StringBuilder jsonString = new StringBuilder();
        jsonString.append("[");

        List categorys = categoryManager.getRoot();
        int i = 0;
        for (Category category : categorys) {
            if (i > 0) {
                jsonString.append(",");
            }
            jsonString.append(toJSONString(category));
            i++;
        }

        jsonString.append("]");
        return jsonString.toString();
    }
    // ==================== 产生jquery.treeview的jsonstring 结束=================//
}

package com.prl.action.admin.helper;

import java.util.List;

import javax.servlet.http.HttpServletRequest;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import org.springside.modules.web.struts2.Struts2Utils;

import com.prl.entity.Category;
import com.prl.service.CategoryManager;
import com.prl.service.jdbc.CategoryJdbcUtil;

@Repository
public class CategoryHelper {
	private static final Log log = LogFactory.getLog(CategoryHelper.class);
	@Autowired
	public CategoryManager categoryManager;
	@Autowired
	public CategoryJdbcUtil categoryJdbcUtil;

	// ========================= 产生jquery.treeview的jsonstring=================//
	public String generateJTVJsonString() {
		log.info("generateJTVJsonString start .....");
		HttpServletRequest request = Struts2Utils.getRequest();
		String id = request.getParameter("root");
		log.info("id:"+id);
		String output = "";
		if (id == null) {
			return "";
		} else if (id.equalsIgnoreCase("source")) {
			output = generateInitTreeString();
		} else {
			output = generateTreeChildNodeString(Long.parseLong(id));
		}
		log.info("generateJTVJsonString end,return:"+output);
		return output;
	}

	// 产生子节点jsonstring
	private String generateTreeChildNodeString(Long categoryId) {
		StringBuilder jsonString = new StringBuilder();
		jsonString.append("[");

		List categorys = categoryManager
				.findChildrenCategory(categoryId);
		if (categorys.isEmpty())
			return "";
		int i = 0;
		for (Category category : categorys) {
			if (i > 0) {
				jsonString.append(",");
			}
			jsonString.append(toJSONString(category));
			i++;
		}

		jsonString.append("]");
		return jsonString.toString();
	}

	private String toJSONString(Category category) {
		StringBuilder sb = new StringBuilder();
		sb.append(" {");
		sb.append("  \"text\": \"" + generateLinkString(category) + "\"");

		if (categoryJdbcUtil.hasChild(category)) {
			sb.append(",  \"id\":\"" + category.getCatId() + "\"");
			sb.append(",  \"hasChildren\":true");
		}
		sb.append(" }");
		return sb.toString();
	}

	private String generateLinkString(Category category) {
		String link = "" + category.getCatName() + "";
		//link = category.getCatName();
		return link;
	}

	private String generateInitTreeString() {
		StringBuilder jsonString = new StringBuilder();
		jsonString.append("[");

		List categorys = categoryManager.getRoot();
		int i = 0;
		for (Category category : categorys) {
			if (i > 0) {
				jsonString.append(",");
			}
			jsonString.append(toJSONString(category));
			i++;
		}

		jsonString.append("]");
		return jsonString.toString();
	}
	// ==================== 产生jquery.treeview的jsonstring 结束=================//
}

 

 

写完收功，希望能帮到正在使用这个treeview的朋友点小忙，自己以后再使用的时候，也可以再翻看一下这篇笔记，不至于搞忘记用法了。