Jtree with its Modules

[seema chhetri]

Hello ,

I have made one Jtree in which its have 26 modules around when i click on any of them again all 26 modules is coming from that node please see my code and let me know what to do.


Thanks
seema

[Rob Spoor]

I couldn't compile your code because of several missing classes, but your TreeModel code looks really bogus. There are always 2 children (getChildCount), but if the JTree tries to get these it always gets a completely new object. If it then try to get the index of an object, 0 is always returned. And nothing is a leaf, ever.

The following are usual implementations:
- each object has an associated List (or array); let's call it children
- getChildCount(o) returns children.size() (children.length for the array)
- isLeaf(o) returns children.isEmpty() (children.length == 0 for the array)
- getIndexOfChild(o, child) returns children.indexOf(child) (a loop to retrieve the index for the array)
- getChild(o, index) returns children.get(index) (children[index] for the array)

Usually this List (or array) is stored as part of the object (e.g. DefaultMutableTreeNode) or can be constructed using the object.

For instance, a naive (very slow) File tree model (missing a few methods):

class FileTreeModel implements TreeModel
{
    private File root;

    public FileTreeModel(File root) { this.root = root; }

    public Object getRoot() { return root; }

    public int getChildCount(Object o)
    {
        File file = (File)o;
        File[] children = file.listFiles();
        return (children == null ? 0 : children.length);
    }

    public Object getChild(Object o, int index)
    {
        File file = (File)o;
        File[] children = file.listFiles();
        return children[index];
    }

    public int getIndexOfChild(Object o, Object child)
    {
        File file = (File)o;
        File[] children = file.listFiles();
        for (int i = 0; i < children.length; i++)
        {
            if (children[i].equals(child) { return i; }
        }
        return -1;
    }

    public boolean isLeaf(Object o)
    {
        return getChildCount(o) == 0;
    }

    // missing methods should go here
}

[seema chhetri]

Hello,


thanks for repplying .but the main problem is that i dont want any leaf. I only want root then after this modules no child of these modules.

please tell me what can be possible for this code.


Thanks