example app for how to get all the items in the timeline

TimelineItems

#include "cinder/app/App.h"
#include "cinder/app/RendererGl.h"
#include "cinder/gl/gl.h"

#include "cinder/Timeline.h"

#include "cinder/Rand.h"

using namespace ci;
using namespace ci::app;
using namespace std;


//typedef std::shared_ptr<class CustomTimeline> CustomTimelineRef;
//class CustomTimeline : public ci::Timeline{
//public:
//
//    std::multimap<void*, TimelineItemRef> getItems() { return mItems; }
//};

class CustomTimelineApp : public App {
public:
    void setup() override;
    void mouseDrag( MouseEvent event ) override;
    void keyUp ( KeyEvent event  ) override;
    void update() override;
    void draw() override;
    
    
    TimelineRef mSequencer;
    Anim<float> mAnim;
    
    ci::Color mCurrentColor { 0.8f, 0.9, 0.1 };
    
    
    bool up = true;
};

void CustomTimelineApp::setup()
{
    
    
    mSequencer = Timeline::create();
    mSequencer->setInfinite(false);
}

void CustomTimelineApp::mouseDrag( MouseEvent event )
{
    
    auto normX = float(event.getX()) / float(getWindowWidth() - 200);
    mSequencer->stepTo( normX * mSequencer->getDuration());
    mSequencer->setLoop(true);
    
}

void CustomTimelineApp::keyUp(cinder::app::KeyEvent event){
    
    if( event.getChar() == ' ' ){
        
        if(  up ){
            mSequencer->appendTo(&mAnim, 1.0f , Rand::randFloat(0.5, 2.0f)).delay(1.0f).autoRemove(false);
        }else{
            mSequencer->appendTo(&mAnim, 0.0f , Rand::randFloat(0.5, 2.0f)).delay(1.0f).autoRemove(false);
        }
        
        up = !up;
    }else{
        
        
        mSequencer->add([&]{
            
            static int  i = 0;
            console() << "cue!" << i << endl;
            
            mCurrentColor = ColorT<float>(CM_HSV, randFloat(0, 1), 0.75, 0.75);
            
            i++;
            
        }, mSequencer->getCurrentTime() + 5)->setAutoRemove(false);
        
    }
}

void CustomTimelineApp::update()
{
    mSequencer->step(1.f/60.f);
}

void CustomTimelineApp::draw()
{
    gl::clear( Color::gray(0.3) );
    
    //    console() << "--------" << endl;
    //    console() << mSequencer->getCurrentTime() << endl;
    //    console() << mSequencer->getEndTime() << endl;
    //
    auto timeToWindow  = [&] (float t) {
        return ( t / mSequencer->getEndTime()) * (getWindowWidth() - 200);
    };
    
    auto cursor = timeToWindow(mSequencer->getCurrentTime());
    
    gl::color(1.0, .7, 0.7);
    gl::drawLine( { cursor, 0 }, {cursor, getWindowHeight() });
    
    int i = 0;
    for(auto item : mSequencer->getItems() ){
        
        float xPos = timeToWindow( item.second->getStartTime() );
        float length = timeToWindow( item.second->getDuration() );
        

        
        float yPos =  i * 10 + 10;
        auto cue = dynamic_pointer_cast<Cue>( item.second );

        if( cue ){
            gl::drawSolidCircle( {xPos, yPos}, 5.0f);
            
        }else{
            gl::drawSolidRect({ xPos, yPos, xPos + length, yPos + 10 });
        }
        

        i++;
    }

    gl::color( mCurrentColor );
    gl::drawSolidCircle( getWindowCenter(), 100 * mAnim() );
}

CINDER_APP( CustomTimelineApp, RendererGl )