How to set the interactivity of uitreenode to 'off'

Question is in the title,

I have a uitree, with top level nodes and children nodes.

I want to disable the interactivity with the children nodes.

When the top level node is checked/unchecked, the children are checked/uncheckd. But the use cannot uncheck/check the children node .

Answer 1

[Hitesh]

Hi Sylvain,

"uitreenode" objects don't have a direct 'Enable' or 'Interactivity' property to disable user interaction with individual nodes like UI controls do. However, you will be able to simulate non-interactivity by using the Checked property and controlling behavior via a callback, essentially preventing user-initiated changes on the child nodes. Kindly follow the below approach to set the interactivity of uitreenode to 'off'.

1. Use the CheckedNodesChangedFcn of the uitree.
2. Revert any user interaction with the child nodes.
3. Allow interaction only through the top-level node.

Refer to following code as an example.

fig = uifigure;
t = uitree(fig, 'checkbox', 'Position', [20 20 200 200]);

% Create top-level node
topNode = uitreenode(t, 'Text', 'Parent Node');

% Create child nodes
child1 = uitreenode(topNode, 'Text', 'Child 1');
child2 = uitreenode(topNode, 'Text', 'Child 2');

% Expand top-level node to show children
expand(topNode);

% Store list of read-only nodes (children)
readOnlyNodes = [child1, child2];

% Set callback to control interaction
t.CheckedNodesChangedFcn = @(src, event) treeCallback(src, event, topNode, readOnlyNodes);

function treeCallback(src, event, topNode, readOnlyNodes)
    newChecked = src.CheckedNodes;

    if ismember(topNode, newChecked)
        % Top node is checked — enforce all children to be checked
        src.CheckedNodes = vertcat(topNode, readOnlyNodes(:));
    else
        % Top node is unchecked — uncheck all
        src.CheckedNodes = [];
    end
end

For more information regarding "uitreenode", kindly refer to the following MATLAB documentation:

https://www.mathworks.com/help/matlab/ref/uitreenode.html

Answer 2

[Sylvain]

Thank you, shame that such interactivity is not implemented. Your code seems to work OK, but graphically it has some visual glitch which affect the rendering,

I have reconsidered my approach by not using he checked node function, but going for the selected nodes instead. For whoever want to have a try, here is the code:

close all force
clear
clc
buildTreeNode()



function buildTreeNode()
    fig = uifigure;
    tree = uitree(fig, 'Position', [20 20 200 400],'Multiselect','on');
    % Create top-level node
    topNode(1) = uitreenode(tree, 'Text', 'Parent Node 1');
    % Create child nodes
    uitreenode(topNode(1), 'Text', 'Child 1 1');
    uitreenode(topNode(1), 'Text', 'Child 1 2');

    topNode(2) = uitreenode(tree, 'Text', 'Parent Node 2');
    % Create child nodes
    c(1) = uitreenode(topNode(2), 'Text', 'Child 2 1');
    c(2) = uitreenode(topNode(2), 'Text', 'Child 2 2');
    uitreenode(topNode(2), 'Text', 'Child 2 3');
    uitreenode(topNode(2), 'Text', 'Child 2 4');

    cc(1) = uitreenode(c(1), 'Text', 'Child 2 1 1');
    uitreenode(c(1), 'Text', 'Child 2 1 2');
    uitreenode(c(1), 'Text', 'Child 2 1 3');
    uitreenode(c(2), 'Text', 'Child 2 2 1');
    uitreenode(cc(1), 'Text', 'Child 2 1 1 1');


    topNode(3) = uitreenode(tree, 'Text', 'Parent Node 3');
    % Create child nodes
    uitreenode(topNode(3), 'Text', 'Child 3 1');
    uitreenode(topNode(3), 'Text', 'Child 3 2');
    uitreenode(topNode(3), 'Text', 'Child 3 3');
    
    
    % Expand top-level node to show children
    for i=1:length(topNode)
        expand(topNode(i),'all');
    end

    % Select the nodes  
    j = 1;
    tree.SelectedNodes = [tree.Children(j),getAllChildrenCell(tree.Children(j))'];
    tree.SelectionChangedFcn =  @(src, event) treeCallback(src, event);
end


function treeCallback(src, ~)
    selectedNode = src.SelectedNodes;
    src.Multiselect = 'off';
    topnode = findTopNode(src,selectedNode);    
    src.Multiselect = 'on';

    src.SelectedNodes = [topnode,getAllChildrenCell(topnode)'];
end

function node = findTopNode(tree,node)
    if length(node)>1
        node = node(1);
    end

    if ismember(node.Parent,tree)
        disp("top node selected")
    else
        disp("child node selected, looking for parent node")
        node = findTopNode(tree,node.Parent);
    end

end


function allChildren = getAllChildrenCell(node)
    allChildren = {};
    function collectChildren(currentNode)
        children = currentNode.Children;
        if ~isempty(children)
            allChildren{end+1} = children;
            for i = 1:length(children)
                collectChildren(children(i));
            end
        end
    end
    collectChildren(node);
    % Flatten the cell array
    allChildren = vertcat(allChildren{:});
end