What is jsTree?
jsTree is jquery plugin, that provides interactive trees. It is absolutely free, open source and distributed under the MIT license. jsTree is easily extendable, themable and configurable, it supports HTML & JSON data sources and AJAX loading.
jsTree functions properly in either box-model (content-box or border-box), can be loaded as an AMD module, and has a built in mobile theme for responsive design, that can easily be customized. It uses jQuery's event system, so binding callbacks on various events in the tree is familiar and easy.
Just a few of the features worth noting:
- drag & drop support
- keyboard navigation
- inline edit, create and delete
- tri-state checkboxes
- fuzzy searching
- customizable node types
- Root node 1
- initially selected
- custom icon URL
- initially open
- Another node
- Custom icon class (bootstrap)
- Root node 2
Populating the tree using JSON
The format
jsTree needs a specific format to work with JSON. In the standard syntax no fields are required - pass only what you need. Keep in mind you will be able to access any additional properties you specify - jsTree won't touch them and you will be able to use them later on (using the original
property on each node).
To change the icon of the node use the icon
property. Specifying a string containing a /
will display that image as the node icon. Using any other string will apply that class to the <i>
element that is used to represent the icon. You can use boolean false
to make jsTree render the node with no icon.
You can set the state on a node using the state
property. Use any combination of the following: opened
, selected
, disabled
.
Both li_attr
and a_attr
are passed directly to jQuery's attr function.
When using AJAX set children
to boolean true
and jsTree will render the node as closed and make an additional request for that node when the user opens it.
Any nested children should either be objects following the same format, or plain strings (in which case the string is used for the node's text and everything else is autogenerated).
// Expected format of the node (there are no required fields)
{
id : "string" // will be autogenerated if omitted
text : "string" // node text
icon : "string" // string for custom
state : {
opened : boolean // is the node open
disabled : boolean // is the node disabled
selected : boolean // is the node selected
},
children : [] // array of strings or objects
li_attr : {} // attributes for the generated LI node
a_attr : {} // attributes for the generated A node
}
Alternative JSON format
If you do not want to use the nested children
approach, you can use the alternative syntax where each node object has two required fields: id
& parent
and no children
property (everything else remains the same).
jsTree will automatically build the hierarchy. To indicate a node should be a root node set its parent
property to "#"
.
This should be used mainly when you render the whole tree at once and is useful when data is stored in a database using adjacency.
// Alternative format of the node (id & parent are required)
{
id : "string" // required
parent : "string" // required
text : "string" // node text
icon : "string" // string for custom
state : {
opened : boolean // is the node open
disabled : boolean // is the node disabled
selected : boolean // is the node selected
},
li_attr : {} // attributes for the generated LI node
a_attr : {} // attributes for the generated A node
}
Using JSON
To populate the tree with a JSON object you need to use the $.jstree.defaults.core.data
config option.
The expected format is an array of nodes, where each node should be an object as described above or a simple string (in which case the string is used for the node's text property and everything else is autogenerated). Any nested nodes are supplied in the same manner in the children
property of their parent.
$('#using_json').jstree({ 'core' : {
'data' : [
'Simple root node',
{
'text' : 'Root node 2',
'state' : {
'opened' : true,
'selected' : true
},
'children' : [
{ 'text' : 'Child 1' },
'Child 2'
]
}
]
} });
Using the alternative JSON format
$('#using_json_2').jstree({ 'core' : {
'data' : [
{ "id" : "ajson1", "parent" : "#", "text" : "Simple root node" },
{ "id" : "ajson2", "parent" : "#", "text" : "Root node 2" },
{ "id" : "ajson3", "parent" : "ajson2", "text" : "Child 1" },
{ "id" : "ajson4", "parent" : "ajson2", "text" : "Child 2" },
]
} });
Using AJAX
You can also use AJAX to populate the tree with JSON your server returns. The format remains the same as the above, the only difference is that the JSON is not inside the config object, but returned from the server.
To take advantage of this option you need to use the $.jstree.defaults.core.data
config option.
Just use a standard jQuery-like AJAX config and jstree will automatically make an AJAX request populate the tree with the response.
In addition to the standard jQuery ajax options here you can supply functions for data
and url
, the functions will be run in the current instance's scope and a param will be passed indicating which node is being loaded, the return value of those functions will be used as URL and data respectively.
If you do not return correct json headers from the server, at least set the dataType
jQuery AJAX option to "json"
.
$('#tree').jstree({
'core' : {
'data' : {
'url' : function (node) {
return node.id === '#' ?
'ajax_roots.json' :
'ajax_children.json';
},
'data' : function (node) {
return { 'id' : node.id };
}
}
});
Using a function
You can supply a function too. That function will receive two arguments - the node being loaded and a callback function to call with the children for that node once you are ready.
$('#tree').jstree({
'core' : {
'data' : function (obj, cb) {
cb.call(this,
['Root 1', 'Root 2']);
}
}});