addChildNode() {
        this.changesMade = true;

        const pnode = this.tree.selectedNode();
        const point = this.idl.create('vmsp');
        point.id(this.newId--);
        point.isnew(true);
        point.parent(pnode.id);
        point.match_set(this.matchSet_.id());
        point.children([]);

        const ptype = this.newPoint.values.pointType;

        if (ptype === 'bool') {
            point.bool_op(this.newPoint.values.boolOp);

        } else {

            if (ptype === 'attr') {
                point.svf(this.newPoint.values.recordAttr);

            } else if (ptype === 'marc') {
                point.tag(this.newPoint.values.marcTag);
                point.subfield(this.newPoint.values.marcSf);
            } else if (ptype === 'heading') {
                point.heading(true);
            }

            point.negate(this.newPoint.values.negate);
            point.quality(this.newPoint.values.matchScore);
        }

        const node: TreeNode = new TreeNode({
            id: point.id(),
            callerData: {point: point}
        });

        // Match points are added to the DB only when the tree is saved.
        this.setNodeLabel(node, point).then(() => pnode.children.push(node));
    }

 isRootNode(): boolean {
     const node = this.tree.selectedNode();
     if (node && this.tree.findParentNode(node) === null) {
         return true;
     }
     return false;
 }

 selectedIsBool(): boolean {
     if (this.tree) {
         const node = this.tree.selectedNode();
         return node && node.callerData.point.bool_op();
     }
     return false;
 }

 hasSelectedNode(): boolean {
     return Boolean(this.tree.selectedNode());
 }

 deleteNode() {
     this.changesMade = true;
     const node = this.tree.selectedNode();
     this.tree.removeNode(node);
 }