TreeViewWidget.jl

A minimal TreeView widget for use in Jupyter notebooks (and maybe Blink)

    julia>]add TreeViewWidget

Create a treeview widget from a treeview structure:

    tree = TreeViewRoot()
    beverages = TreeViewNode("Beverages")
    push!(beverages, TreeViewNode("Water"))
    push!(beverages, TreeViewNode("Tea"))
    push!(tree, beverages)
    push!(tree, TreeViewNode("Food"))

    treeview = TreeView(tree)

The elements with children are shown as collapsed nested structures. You can expand them by clicking on the > icon. The text of each element can be selected. Use CTRL+Click to select multiple elements.

The selection is available in Julia via an Observable. This is an array of dictionaries with the text label treeview[][1]["label"] and the identifier treeview[][1]["id"] which is also present in each TreeViewNode.

    julia> treeview[]
2-element Array{Dict{String,String},1}:
 Dict("label" => "Tea","id" => "654c1dbc-a4c4-42ec-9290-b27ce6165993")
 Dict("label" => "Food","id" => "8c26fdf9-9d4b-4f04-ae54-0f94ad21603c")

You can automatically do things whenever the user clicks something using on from Observables:

    using Observables
    h = on(treeview[]) do selected
        if !isempty(selected)
            println("The first selected label is: ", selected[1]["label"])
        end
    end

The TreeViewNode identifier is unique and can be used to retrieve the node from the TreeView and TreeViewRoot. Given the example above you can find the Tea Node via:

    treeview["654c1dbc-a4c4-42ec-9290-b27ce6165993"]

Or directly via one of the array elements returned by the Observable

    selected = treeview[]
    treeview[selected[1]]

You can also store data directly in each TreeViewNode, for later retrieval

    TreeViewNode(label = "Tea", data=5.0)