---
name: "tlp_Observer"
section: "3tulip"
platform: "linux"
package: "tulip-doc"
version: "3.1.2-2.3"
release: "Debian 6.0 (Squeeze)"
platforms: ["linux"]
url: "https://new.carta.tech/tlp_Observer"
---

# tlp\_Observer(3tulip)

## NAME

tlp::Observer -

## SYNOPSIS

`#include <Observable.h>`

### Public Member Functions

virtual **~Observer** ()\
 virtual void **update** (std::set\< **Observable** \* \>::iterator begin, std::set\< **Observable** \* \>::iterator end)=0\
 virtual void **observableDestroyed** (**Observable** \*)=0\

## Detailed Description

The **Observer** pattern is a framework for handling state dependency between observer and observed object. It is described in the lecture notes and pp293-304 of Design Patterns by Gamma, Helm, Johnson, and Vlissides.

## Constructor & Destructor Documentation

### virtual tlp::Observer::~Observer ()` [inline, virtual]`

## Member Function Documentation

### virtual void tlp::Observer::observableDestroyed (Observable \*)` [pure virtual]` Methods called when an observable has been deleted. holdObservers and unHoldObservers function have no effects on this function.

### virtual void tlp::Observer::update (std::set\< Observable \* \>::iterator begin, std::set\< Observable \* \>::iterator end)` [pure virtual]` Methods called when a change occur in the observed objects Due to the possibility to differs notificatiosn several objects can send a notify events simultaneously. The iterators given in parameter enable to iterate all these objects.

## Author

Generated automatically by Doxygen for Tulip Graph Library from the source code.