inviwo::Observable< T > Class Template Reference

Class to support observer pattern. More...

#include <inviwo/core/util/observer.h>

Inheritance diagram for inviwo::Observable< T >:

Public Member Functions
void	addObserver (T *observer)
bool	isObservedBy (T *observer) const
	Observable (const Observable< T > &other)
	Observable (Observable< T > &&other) noexcept
Observable< T > &	operator= (const Observable< T > &other)
Observable< T > &	operator= (Observable< T > &&other) noexcept
void	removeObserver (T *observer)
virtual void	startBlockingNotifications () override final
virtual void	stopBlockingNotifications () override final

Protected Member Functions
template<typename C>
void	forEachObserver (C callback)
Protected Member Functions inherited from inviwo::ObservableInterface
void	addObservationHelper (Observer *observer)
void	removeObservationHelper (Observer *observer)

Detailed Description

template<typename T>
class inviwo::Observable< T >

Class to support observer pattern.

Example of how to apply it to a simple button.

class ButtonObservable;
 
class IVW_XXX_API ButtonObserver: public Observer {
public:
    friend ButtonObservable;
    // Override to be notified when the observed button is pressed.
    virtual void onButtonPressed(){};
};
 
class IVW_XXX_API ButtonObservable: public Observable<ButtonObserver> {
protected:
    void notifyObserversAboutButtonPressed() {
        forEachObserver([](ButtonObserver* o) { o->onButtonPressed(); });
    }
};

Usage:

class Button : public ButtonObservable {
    ...
    void handleButtonPress() {
        ...
        notifyObserversAboutButtonPressed();
        ...
    }
    ...
};

class MyClass : public ButtonObserver {
public:
    MyClass(Button* button) {
        button->addObserver(this);
    }
 
    ...
private:
    virtual void onButtonPressed() override {
        // Do stuff on button press
    };
    ...
};

See also

Observer

VoidObserver

Constructor & Destructor Documentation

Observable() [1/2]

template<typename T>

inviwo::Observable< T >::Observable

(

const Observable< T > &

other

)

This operation does nothing. We will not touch the observers of other.

Observable() [2/2]

template<typename T>

inviwo::Observable< T >::Observable ( Observable< T > && other )

noexcept

This operation will remove all observers from other and add them to this.

Member Function Documentation

operator=() [1/2]

template<typename T>

Observable< T > & inviwo::Observable< T >::operator=

(

const Observable< T > &

other

)

This operation does nothing. We will not touch the observers of other.

operator=() [2/2]

template<typename T>

Observable< T > & inviwo::Observable< T >::operator= ( Observable< T > && other )

noexcept

This operation will remove all observers of this, and make all observers of other observe this instead.

startBlockingNotifications()

template<typename T>

void inviwo::Observable< T >::startBlockingNotifications ( )

finaloverridevirtual

Implements inviwo::ObservableInterface.

stopBlockingNotifications()

template<typename T>

void inviwo::Observable< T >::stopBlockingNotifications ( )

finaloverridevirtual

Implements inviwo::ObservableInterface.

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The documentation for this class was generated from the following file:

• include/inviwo/core/util/observer.h