laszlo: Working with laszlo trees

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1. Base tree source code

From the programming forum

An interesting thread on trees

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Docs

Basetree You can subclass basetree to build a tree control with your own look and feel. Basetree has two content areas: item and children. The item view is where the visual component of the tree should be placed. Any view that you want to place in the tree node should be placed in item. You can use placement="item". The children view is the defaultplacement for basetree.

lzTree A derived tree with auto options 

(canvas height="620")
(include href="lz/tree.lzx"/)

You have to include the ls/tree.lzx at the top. Otherwise you get all kinds of compiler errors

Can I create a tree object on the fly by going through an xml data set?

In populating trees all the tree examples are using a * syntax for specifying datapaths. What is its significance?

In populating trees from data sets they are using a 


$path{'@name'}

syntax. What the hell is it. I know that $ is a constraint by looking at their language manual. But there is no "path" being constraint.

It is still a mystery how a tree is populated using the data replication techniques. The standard metaphor is confusing. Clarify this

1. Read the language manual

2. Read the guide to see if we can get some clarity on data replication and xpath

Read this indepth chapter on events, methods, and attributes.

An http dataset may have arguments into it. You may want to set this at run time. How is this done.

A node requires a name, text, and attributes. What is the syntax. Especially the attributes.

Apparently when instantiating a node you will need a dictionary object for its attributes. There doesn't seem to be docs on this. Check the forum for it.

Apparently this is done through duplicating a data pointer and doing an addnode using that data pointer. But if you have a whole data set to add you may have to walk through each child node and add it to them. See if you can write a utility function to do this.

After I update a tree data, how can I tell the tree to refresh itself with the new nodes?

Tress and their underlying data sets. Issues, solutions etc.