beforeAdd

fires before adding a new item into a tree collection

beforeAdd: (newItem: object) => boolean | void;

Parameters:

• newItem: object - the object of an added item

Returns:

Return false to prevent adding of an item; otherwise, true.

Example

component.data.events.on("beforeAdd", function(newItem){
    console.log("A new item will be added");
    return true;
});