# serverList

### Description

@short: Defines a named collection that can be loaded into Units, Timeline views, or the Lightbox

@signature: serverList: (list_name: string, options?: any[]) =\> any[]

### Parameters

- `list_name` - (required) *string* - the name of a list
- `options` - (optional) *array* - optional, an array of options

### Returns
- ` list` - (array) - a list of options

### Example

~~~jsx
//returns a list of options with the name 'my_list'
var list = scheduler.serverList("my_list"); 
...
//creates and returns the specified list
var list = scheduler.serverList("options", [
    {key: 1, label: "John"},
    {key: 2, label: "Adam"},
    {key: 3, label: "Diane"}
]);
~~~

### Related samples
- [Populating a select editor from the server](https://docs.dhtmlx.com/scheduler/samples/01_initialization_loading/09_connector_options.html)
- [Loading Units sections from the server](https://docs.dhtmlx.com/scheduler/samples/03_extensions/17_connector_units.html)
- [Multiselect control in the lightbox](https://docs.dhtmlx.com/scheduler/samples/03_extensions/21_multiselect_options.html)

### Details

- If the method is called only with the first parameter, the method will return a list with that name (if exists).
- If the method is called with 2 parameters, the scheduler will create a list with the specified name or,if a list with such name already exists, the scheduler will rewrite it

Lists, created with the method, can be after updated with the [updateCollection](api/method/updatecollection.md) method.

That's why, if there is a need to update collections, e.g. select options, a list of units in the Timeline, Units view, 
it's a good idea to create them as a named list of options.

~~~js
scheduler.serverList("sections", [
    { key: 1, label: "Section A" },
    { key: 2, label: "Section B" },
    { key: 3, label: "Section C" },
    { key: 4, label: "Section D" }
]);

scheduler.config.lightbox.sections = [
    { 
        name: "description", height: 130, map_to: "text", type: "textarea", 
          focus: true 
    },
    { 
        name: "sections", type: "select",
          options: scheduler.serverList("sections"), map_to: "section_id"  /*!*/
    },
    { 
        name: "time", height: 72, type: "time", map_to: "auto" 
    }
]; 
...
// the same, but with the "units" list
scheduler.createUnitsView({
    name: "unit",
    property: "section_id",
    list: scheduler.serverList("sections") /*!*/ 
});

scheduler.createTimelineView({
    name: "timeline",
    x_unit: "minute",
    x_date: "%H:%i",
    x_step: 30,
    x_size: 24,
    x_start: 16,
    x_length: 48,
    y_unit: scheduler.serverList("sections"), /*!*/
    y_property: "section_id",
    render: "bar"
});

scheduler.init("scheduler_here", new Date(), "unit");
~~~

Then, at a later point in time, it will be possible to change options on all these places by calling [scheduler.updateCollection](api/method/updatecollection.md):

~~~js
scheduler.updateCollection("sections", [
    { key: 5, label: "Section E" },
    { key: 6, label: "Section F" },
    { key: 7, label: "Section G" }
]);
~~~

### Related API
- [updateCollection](api/method/updatecollection.md)