Question

In my XML file I have a node which is there per layer node like so:

<layer name="Tile Layer 1" width="30" height="30">
  <data>
   <tile gid="69"/>
   <tile gid="69"/>

and

<layer name="Collsions" width="30" height="30">
  <data>
   <tile gid="0"/>
   <tile gid="0"/>
   <tile gid="0"/>

Now if I use the following statement using xpath

xmlChar *xpath = (xmlChar*) "//tile/@gid";

I can get all the tile gids. My issue is I would like to retrieve tile gids for just the collisions layer.

Some pseudo:

//get to layer node
if(name == collision)
{
   get tile gids for this node list only
}

How do I do this?

I tried using the currentNode->xmlChildrenNode and it went down the nodes, but for some reason it returned “text” at one point? Is this due to whitespace?

I use this in the following code(expression changed to xmlChar *xpath = (xmlChar*) "/layer[@name=\"Collisions\"]/data/tile/@gid";

xmlChar *xpath = (xmlChar*) "/layer[@name=\"Collisions\"]/data/tile/@gid";//"//tile/@gid";
xmlNodeSetPtr nodeset;
xmlXPathObjectPtr result;
int i;
xmlChar *keyword;
int numCollisionTiles = 0;

result = getnodeset (doc, xpath);
if (result) 
{
    nodeset = result->nodesetval;
    for (i=0; i < nodeset->nodeNr; i++) 
    {
        keyword = xmlNodeListGetString(doc, nodeset->nodeTab[i]->xmlChildrenNode, 1);

        int id = atoi(keyword);
        int index = i;
        if(id == 111)
        {
            numCollisionTiles += 1;
            index -= 899;
            printf("tile id : %d for index: %d\n", id, index);
        }

        xmlFree(keyword);
    }
    xmlXPathFreeObject (result);
}
printf("number of collision tiles : %d\n", numCollisionTiles);

}

This code works when I use the following xmlChar *xpath = (xmlChar*) "//tile/@gid"

Could the following

keyword = xmlNodeListGetString(doc, nodeset->nodeTab[i]->xmlChildrenNode, 1); 

be causing xmlChar *xpath = (xmlChar*) "/layer[@name=\"Collisions\"]/data/tile/@gid"; to find nothing?

Answer 1

Try this:

/layer[@name="Collisions"]/data/title/@gid

or

//tile[../../@name="Collisions"]/@gid