Monitor changes in Live objects live.observer is used to listen to changes in the values of properties of Live objects. This object works in conjunction with the live.path object, which sends id nn messages into the right inlet of live.observer .

After an object id and property is specified, its value is sent out the left outlet. From this moment on, the value is sent on each change of the property ('notification') as well as in response to bang messages.

The left outlet is reserved for value messages, all other output is sent to the right outlet.

Not all properties can be observed, please consult the Live Object Model to see which can. Also, it is not possible to modify the live set from a notification, i.e. while you are receiving a value message spontaneously sent by a live.observer 's outlet.

Besides properties, it is also possible to observer children of Live objects. Their values are object ids or lists of them.

Note: The Live API runs in the main thread in Live, and that all messages to and from the API are automatically deferred. Cycling '74, Ableton Live Gets all command messages described below. Gets object id message id nn to select the object to operate upon. In response to the id message, the current value of the property, if a property was already selected, is sent out the left outlet.
id 0 means no object, i.e. all messages to the left inlet are ignored, which is also the initial state. Sends the current value of the selected property of the selected object. The value type depends on the property, as described in the Live Object Model, and may be int, float, symbol, id nn or lists of ids. Sends responses to getproperty , gettype , getid . Initial Property Specify a property or child name as argument to live.observer . Arguments:
property the name of a property of the current object

Operation:
Selects the property to be observed. Arguments:
property the name of a property of the current object

Operation:
Selects the property to be observed. Outputs the current value to the left outlet if a proper Live object is selected.

Remark:
Not all properties can be observed.
The types of the properties are given in the Live Object Model.

Outlet	Output	Example
left	value	3.1415926

Arguments:
child the name of a child of the current object

Operation:
Selects the child id to be observed. Outputs the id (or "id 0") Arguments:
child the name of a child of the current object

Operation:
Selects the child id to be observed. Outputs the id (or "id 0") to the left outlet if the selected Live object has such a child.

Remark:
Not all children can be observed.

Outlet	Output	Example
left	id nn	id 17

Arguments:
child the name of a child list of the current object

Operation:
Selects the child list to be observed. Outputs the id list (or nothing) Arguments:
child the name of a child list of the current object

Operation:
Selects the child list to be observed. Outputs the id list (or nothing) to the left outlet if the selected Live object has such a list child.

Remark:
Not all child lists can be observed.

Outlet	Output	Example
left	id nn ... id mm	id 4 id 5

Operation:
Sends the name of the selected property (or child resp. list-child) Operation:
Sends the name of the selected property (or child resp. list-child) out the right outlet.

Outlet	Output	Example
right	property property or property child	property name or property selected_track

Operation:
Sends the type of currently observed property or child to the right outlet. Operation:
Sends the type of currently observed property or child to the right outlet. The types of the properties and children are given in the Live Object Model.

For list-children it just sends type tuple , w/o further type information.

Outlet	Output	Example
right	type property-type or type object-type	type int or type Track

Operation:
Sends the id of the currently observed Live object to the right outlet. Operation:
Sends the id of the currently observed Live object to the right outlet.

Outlet	Output	Example
right	id nn	id 20

Operation:
Sends current value of selected property of current object to the left outlet. Operation:
Sends current value of selected property of current object to the left outlet. Does nothing if no property or no Live object is selected or if they don't match.

Outlet	Output	Example
left	value	Drums

Operation:
Sets the current object. Operation:
Sets the current object. The message has the same effect if sent to both the right or the left inlet. For clarity it is suggested to always use the right inlet to supply the object id.

- no output - The live.observer object has a special entry in its inspector labelled "Use Persistent Mapping". This setting, when enabled, causes the id associated with the object to persist when the Live document is saved and restored, and when the Max Device is moved between the Live application and the Max editor, or within the Live Set. Beginning in Live 8.2.2, Live API ids remain persistent between launches of Live, which in conjunction with the Persistence feature of live.object , live.observer and live.remote~ , makes it possible to create simpler devices which retain their association with elements in the Live user interface.